CA2126751A1

CA2126751A1 - An energy-polymerizable adhesive, coating, film and process for making the same

Info

Publication number: CA2126751A1
Application number: CA002126751A
Authority: CA
Inventors: Peggy S. Willett; Janis Robins; Kent S. Tarbutton; Michael A. Kropp
Original assignee: Individual
Current assignee: 3M Co
Priority date: 1992-01-22
Filing date: 1992-12-22
Publication date: 1993-08-05
Also published as: JP3392866B2; DE69208106D1; JPH07503270A; EP0623152A1; MX9300135A; US5310840A; BR9207060A; IL104248A0; KR940703878A; US5399637A; AU3330093A; DE69208106T2; EP0623152B1; WO1993015125A1; IL104248A; KR100263959B1; TW283159B; US5252694A

Abstract

Polymerizable compositions having at least one cationically polymerizable monomer; an optional free radically polymerizable monomer; an energy-polymerizable catalyst system wherein the catalyst system comprises an organometallic complex salt; a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt; optionally, a peroxide. The polymerized compositions are useful as cured adhesive films, pressure sensitive adhesives, protective coatings, liquid adhesives, structural and semi-structural adhesives, and free standing films.

Description

~0 93/1~12~ 2 1 2 6 7 ~i 1 PCr/~S92/1 1031 AN ENERGY-POLYMERIZABLE ADHESIVE, COATING, FILM
AND PROCESS FOR MAKING THE SAME

BACKGROUND OF THE INVENTION
s Field of the Invention This invention relates to polymerizable compositions comprising an energy-polymerizable catalyst system, and cured adhesive films, pressure sensitive adhesives, protective coatings, liquid adhesives, structural and semi-10 structura1 adhesives, and free-standing films prepared therewith.
cri~don of the Related Art Various polymeric coatings and articles are produced in processes involving the use of organic solvents. There is an intense effort by researchersand industry to promote high and 100% solids formulations and processes to 15 reduce or eliminate the use of such solvents and the attendant costs and environmental contaminat~on.
Radiation dual curable compositions containing unsaturated monomers and epoxy monomers have been described in a number of U.S. Patents Nos.
4,156,035 (Tsao et al.), 4,227,978 ~ton), 4,428,$07 (Lee et al.), 20 4,623,676 (Kistner), 4,657~779 (Gaske), and 4,694,029 (Land). Compositions described iD the a~sremen~oned patents include onium salts combined with organic compounds as the curing system.
U.S. Patent No. 4,717,605 (Ur~an et al.) describes radiati~n curable adhesives based on the combination of an epoxide system and ionic 25 photoinitiators of the triarylsulfonium complex type and at least one ethylenically unsaturated substance that can be polymerized by free radicals and at least one free radical photoinitiator. The adhesive described is a hardenable glue cured by two light exposures.
U.S. Patent No. 4,677,137 (Bany et al.) describes a process using a 30 supported onium salt or an ionic salt of an organometallic complex as the WO 93/1:~12:~ PCI /-S92/1 1031

2 1 ~ li / S t photoinitiator system for the polymerization of cationically polymerizable materials.
U.S. Patent No. 4,707,432 (Gatechair et al.) describes a free radically polymedzable composition comprising a free radically polymerizable material 5 and a photoinitiator system compdsing an alpha-cleavage or homolytic bond cleavage photoinitiator and a ferrocenium salt.
WO 8802879 (Woods et al.) describes a free radically polymerizable composition compdsing a free radically polymerizable matedal and a photoinitiator system comprising a free radical photoinitiator and a 10 ferrocenium salt. Furthermore, the composition may contain one or more cationically polymerizable matedals.
U.S. Pa~ent No. 4,849,320 (Irving ct al.) describes a process using a combination of two different photoinitiators and two different polymedzable monoms in combination with irradiation at two substantially different 15 waveleng~s.
U.S. Patent No. 4,751,138 (Tumey et al.) desc~ibcs a coated abrasive article pr~parcd by polymerizing a combinalion of epoxy and acryhte monomers using a combination of photoinitiators that can be a fer~mium, onium salts or an alpha-cleavage or homolytic bond cleavage photoinitiator.
AU 8538551 (Meier et al.) describes a curable composition containing materials that are polymerizable by free ~adical or cationic mechanisms using an iron containing cationic organometallic compound and an electron acc~ptor as an oxidizing agent. The electron acceptors are preferably an organic hydroperoxide, an organic peracid or a quinone. The utility of this 25 composition is in the preparation of protective coatings, adhesives, putties, or fiber reinforced composites and laminates.
U.S. Patent No. 3,907,706 (Robins) describes a catalyst system comprising a metal salt of a fluoroalkane sulfonic acid and a ~ermally decomposaUe ester reaction product of a tertiary alkyl alcohol and an acid that 30 fonns a chelation complex with the metal ion of the metal salt. In some embodiments, ~e catalyst system includes a buffering compound that retards activity of the catalyst system.

~vo 93/15125 Pcr~S92/l 1031 .... .

3 212~751 SUMMARY OF THE DISCLOSURE
Briefly, in one aspect of the present invendon, a polymeAzable composition is provided comprising (l) at least one cationically polymerizable monomer and (2) a catalyst system comprising (a) at least one organometallic S complex salt, and (b) a thermally decomposabb ester reaction product of a ter~ary alkyl alcohol and an acid that forms a chctation complex with the mctat ion of the organometallic complex satt, and (c) optionally, a peroxide.
In another aspect of the present invention, a polymerizable composition is provided comprising (l) at least one free radicatly polymerizable monomer, 10 (2) at least onc cationicatly polymerizable monomer, and (3) a catatyst system comprising (a) at least one organometaltic complcx salt, (b) a thermally decomposabk ester reastion product of a ~iary aLlcyl alcohol and an acid that forms a chdation complex with the metat ion of the organometaltic complex salt, (c) optionatly, at least one peroxide, and (d) optionatly, at least one free 15 adicat initiator.
Advantagcously, the compositions of thc present invcndon, when utilizcd in 100~ Ieactive coating compositions, substantiatly diminate the generation of industriat solvent waste white reducing cnergy consumption.
In this application:
~multi-color photoinitiation process" means photoinitiation of polymerization by sequentially or simultaneously irradiating a polymerizable mixture with radiation of substantially different wavelengths, such as described in U.S. Patent No. 4~849,320;
"energy-induced curing" means curing or polymerizing by means of 25 electromagnetic radiation (ultraviolet and visible) accelerated particles (including electron beam), and thermal (infrared and heat) means or any combination thereof such as heat and light simultaneously, light then heat or heat then light;
~free radically polymerizable monomer" means at least one monomer 30 that polymenzes by a fre(e-radical mechanism; it can be bireactive and includes acrylates and methacrylates, vinyl esters, and vinyl aromatic compounds;

~0 93~1~12~ PC~/~S92/11031 ~, "cationically polymerizable monomer" means at least one monomer that polymerizes by a cationic mechanism, and it can be bireactive and includes epoxies, cyclic ethers, vinyl ethers, siloxanes, N-vinyl compounds, alpha-olefins, lactams, lactones;
S "~stage" means an intermediate state in a thermosetting resin reactionin which the material softens when heated, and swclls, but does not dissolve in ccrtain liquids, sec ASTM Standard D907-9lb;
~bireactive monomer" means a monomer that contains at least two free radically or two cationically polymcrizable groups and does not contain both lO typcs of groups simultane~usly;
~ bifunctional monomer~ means thosc monomers that contain both at least one frec radically polymerizablc group and at Icast one cadonically polymcdzablc group;
~ catalyticaUy-cffective amount~ mcans a quantity of catalyst sufficicnt 15 to cffect polymedzation of thc curablc composidon to a polymcrized product at least to a dcgrec to causc an increasc in thc viscosity of thc composition;
~ organometallic salt" means an ionic salt of an organometallic complex cadon, whcrein thc cation contains at least one carbon atom of an organic group that is bonded to a metal atom of ~e transition metal series ~F.A.
20 Cotton and G. Wilkinson ~a~i~jc Chemistry 497 (1976));
~ buffer compound" means a substance that when added to a formulation resists a change in hydrogen ion concentration (pH) on addition of an acid or a base;
"transition metal series" means those metals in the Periodic Table 25 Groups IVB, VB, VIB, VIIB, and VIII; and, "polymerizable composition" means a mixture where the ratio of (free radiGIlly polymerizable monomer):(cationically polymerizable monomer) is 0.1:99.9 to 99.9:0.1.

DESCRIPTION OF THE PREFERRED E~OD~ENT(S) The present invention provides a polymerizable epoxy composition aompnsing:

WO93/1512~ 2I26751 PC'r/~S92/11031 (1) at least one cadonically polymerizable monomer;
(2) a catalyst system comprising:
(a) at least one organometallic complex salt, (b) a thermally decomposable ester reacdon product of a S tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, and (c) opdonally, peroxide;
(3) optionally, a buffer compound; and

(4) opdonally, a mono- or polyfunctional alcohol.
In pardcular, the present invention provides a polymerizable epoxy composidon compAsing:
(1) 1 to 99 wt% of at least one cationically polymeAzable monomer;
(2) 0.01 to 20 wt% of a catalyst system compAsing:
(a) 0.01 to 19.99 wt% of at least one organometallic complex salt, ~b) 0.01 to 19.99 wt% of a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, and (c) 0 to 20 wt% of a peroxide;
~3) 0 to 20 wt% of a buffer compound; and (4) 0 to 50 wt% of a mono- or polyfunctional alcohol.
Adjuvants and thermo plastic mate~ials can be added up to approx. 98 weight percent such that the sum of all the eomponents is equal to 100 wt%.
The present invention further provides a polymerizable viscoelastic epoxy-acrylate composition comprising:
(1) at least one free radically polymerizable monomer;
~2) at least one cationically polymeri zable monomer;
(3) a catalyst system compnsing:
(a) at least one organometallic complex salt, wo 93/1~12~ Pcr/-S92/l 1031 2126'~5i 1 ~`"

(b) a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, (c) optionally, peroxide, and ~d) optionally, at least one free radical initiator;
(4) optdonally, a buffer compound; and (S) optdonally, a mono- or polyfunctional alcohol.
In pardcular, the present invendon provides a polymerizable epoxy-acrylate composidon comprising:
(1) 1 to 99 wt% of at least one free radically polymerizable monomer;
(2) 1 to 99 wt% of at least one free cationically polymeIizable monomer;
(3) 0.01 to 20 wt% of a catalyst system compnsing:(a) 0.01 to 19.99 wt% of at least one organometallic complex salt, (b) 0.01 to 19.99 wt% of a thermally decomposable ester reaction product of a tertiary allyl alcohol and an acid that forms a chela~on complex with the metal ion of the organometallic complex salt, (c) 0 to 20 wt% of a pe~oxide, and (d) 0 to 20 wt% of at least one free r~dical initiator;
(4) 0 to 20 wt% of a buffer ~ompound, and (S) O to 50 wt% of a mono- or polyfunctional alcohol.
Adjuvants and/or the~mo plastic materials can be added up to 25 approximately 97 weight percent such that the sum of all the components is equal to lO0 wt.%.
Ca~onically polymerizable monomers include epoxy-con~ining materials, alkyl vinyl ethers, cyclic ethers, s~rene, divinyl benæne, vinyl toluene, N-vinyl compounds, l-aUyl olefins (alpha~lefins), lactams and cyclic 30 acetals.
Epoxy-containing materials that can be cured or polymerized by the catalyst system of this invention are those h~own to undergo cationic wo 93/l~l25 2 1 ~ 6 7 5 1 Pcrt~S92/1 1031 polymerization and include 1,2-, 1,3-, and 1,4-cyclic ethers (also designated as 1,2-, 1,3-, and 1,4-epoxides). The 1,2-cyclic ethers are preferred.
Cyclic ethers that can be polymerized in accordance with this invention include those described in Frisch and Reegan Rin~-Openin~ Polymerizations

5 Vol. 2 (1969). Suitable 1,2-cyclic ethers are the monomeric and polymeric types of epoxides. They can be aliphatic, cycloaliphatic, aromatic, or hetcrocyclic and will typically have an epoxy cquivalence of from 1 to 6, prefaably I to 3. Particularly useful arc the aliphatic, cycloaliphatic, and glycidyl ctha typc 1,2-cpoxides such as propylene oxide, cpichlorohydrin, 10 StyrGne oxide, vinylcyclohexene oxide, vinylcyclohexene dioxide, glycidol, butadiene oxide, diglycidyl ether of bisphenol A, cyclohexene oxide, 3,4-epoxycyclohexylmethyl-3,4 epoxycyclohexanet arboxylate, 3,4-cpoxy~methylcyclohexylmethyl-3,4-epoxy~methylcyclohexanecarboxylate, IS bis(3,4-epoxy~methylcyclohexylmethyl)adipate, dicyclopentadiene dioxide, epoxidized polybutadiene, 1,4-butanediol diglycidyl ether, polyglycidyl ether of phenolformaldehyde resole or novolak resin, resorcinol diglycidyl ether, and epoxy silicones, e.g., dimethylsiloxanes having cycloaliphatic cpoxide or glycidyl cther groups.
A wide variety of commercial cpoxy resins are available and listed in Lee and Neville Handbook of Epoxy Resins (1967) and in P. Bruins Epoxy Resin Technolo~y (1968). Representative of the 1,3-and 1,4-cyclic ethers which can be polymerized in accordance with this invention are oxetane, 3,3-bis(chloromethyl)oxetane, and tetrahydrofuran.
In particular, cyclic ethers which are readily available include pro~ylene oxide, oxetane, epichlorohydrin, tetrahydrofuran, styrene oxide, cyclohexene oxide, vinylcyclohexene oxide, glycidol, octylene oxide, phenyl glycidyl ether, 1,2-butane oxide, diglycidyl ether of bisphenol A (e.g., "Epon 828" and DER 331"), vinylcyclohexene dioxide (e.g., "ERL~206"), 30 3,4-epoxycyclohexylmethyl-3,4- epoxycyclohexanecarboxylate (e.g., "ERL~4221 "), 3,4-epoxy-~mèthylcyclohexylmethyl-3 ,4-epoxy-~methylcyclohexanecarboxyla WO 93/1~12~ PCl /~S92/1 1031 ~ .,6 ~ 8-te (e.g., "ERL-4201"), bis(3,4-epoxy-~methylcyclohexylmethyl)adipate (e.g., "ERL-4299"), aliphatic epoxy modified with polypropylene glycol (e.g., "ERL-4050" and "ERL-4052"), dipentene dioxide (e.g., "ERL- 4269"), epoxidized polybutadiene (e.g., "Oxiron 2001"), silicone epoxy (e.g., S ~Syl-Kem 90~), 1,4-butanediol diglycidyl ether (e.g., Araldite RD-2), polyglycidyl ether of phenolformaldehyde novolak (e.g., "DER- 431"), Epi-Rez 521" and "DER-438"), resorcinol diglycidyl ether (e.g., Kopoxite"), polyglycol diepoxide (e.g., ~DER-736~), polyacrylate epoxide (e.g., "~pocryl U-14~), urethane modified epoxide (e.g., ~QX3599"), polyfunctional flexible 10 ep~xides (e.g, "Plexibilizer 151~), and mixtures thereof as well as mixtures tnereof with co-curatives, curing agents or hardeners which also are well known (see Lee and Neville and Bruins, supra). Representative of the co curatives ~f hardeners that can be used are acid anhydrides such as nadic methyl anhyddde, cyclopentanc~aca-boxylic dianhydride, pyromellitic lS anhyddde, cis-1,2-cyclohexanedica~oxylic anhydride, and mixtures thereof.
Free radically polymeriz~ble monomers can be selected from (meth)acrylates and vinyl ester functionalized materials. Of particular use are (mcth)asrylates. They can be monomers and/or oligomers such as (meth)acryl~tes (meth)acrylamides, vinyl pyrrolidinone and azlactones. Such 20 monomers include- mono-, di-, or polyacrylates and methacrylates such as methyl acrylate, methyl methacrylate, ethyl acrylate, isopropyl methac~ylate, isooctyl acrylate, acrylic acid, n-hexyl acrylate, stearyl acrylate, allyl acrylate, glycerol diacrylate, glycerol tnacrylate, ethyleneglycol diacrylate, diethyleneglycol diacrylate, triethyleneglycol dimethacrylate, 1,3-propanediol 25 diacrylate, 1,3- propanediol dimethacrylate, trimethanol triacrylate, 1,2,4-butanetriol trimethylacrylate, 1,4-cyclohexanediol diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, pentaerythritol tetramethacrylate, sorbitol hexacrylate, bistl-(2-acryloxy)]-p-ethoxyphenyl dimethylmethane, 30 bistl-(3-acryloxy-2-hydroxy)]-~propoxyphenyl-dimethylmethane, tris-hydroxyethyl isocyanurate trimethacrylate; the bis-acrylates and bis-methacrylates of polyethylene glycols of molecular weight 200 500, 9 21267~1 copolymaizablc mDcn~s of ac~yh~ monomcrs such as those des~i~cd in U.S. Patcnt No. 4,652,274 (Bocttcha et al.), and acrylated o3igom~s such as ~osc des~ibet in TJ.S. Paten~ No. 4,642,126 (Zador ct al.), and such d~iptions arc incorporatcd herein by rcfe~ cc.
Bifunctional monomcrs may also bc uset ant cxamplcs that ~c uscful in ~is i~ cn~on poss~s at kast onc froc sadically ant onc cation~cally rca~i~vc fu~onality. E~amplcs of such mono~s includc, for c%amplc, ~Iycityl a~$ylatc, glycityl mc~ylatc, hyd~o~ycthyl acrylatc, hydro%ycthyl m~htc, hydroxypropyl mc~yh~htc, and hydro%ybutyl acrylatc.
Suitablc or~omctallic comE~c% salt in~ludc thosc d~ L~ U.S.
P~t No. 5,059,701 ~Keipcrt), ant such d~ is i~d hc~ by re~ L~ addi~on to thc organo~ic compk~c sal~s d~ in U.S.
P~t No. S,059,701 aD thc or~omc~ compl~ sal~ d~ib~ in EPO
No. 109,8Sl ~o~o ct ~L) are ~Iso uscf~ i~ tbc p~t i~.
lS Tne p~ or~no~ co~la~ salts us~ iD tbc pr~0t in~t~
bsve tbc fo~owing fonnula Y. (l J
w~
M~ rc~ts a mctal sdec~d from ~c group coOg of: Cr, Mo, W, Mn Re, ~:c, and Co;
Ll re~ts 1 or 2 tigaDdS contr~bu~g pi~s ~ c samc or di~e~ent rtgant sdec~d ~om ~e group of: subs~tutet ;~d unsubs~ c~3-allyl, cta5-cyc~tad;.c~yl, and cta~-cyclohcptatricnyl, ant e~' aroma~ic compounds sdectct 2S ~om cta~-bu~zenc and subs~tuted esl6-b~c compounts and compounds having 2 to 4 fuset ~gs, cac~ c~blc of contsibu~ng 3 to 8 pi-de~rons to thc valencc shdl of ~;
ffits nonc, or 1 to 3 ligants conln7udng an cven numba of sigma ele~rs ~at can bc thc sa~nc or diffctcnt ligand sdec~d from ~c g~ of: c~n mono~udc, Mtrosonium, tnphcnyl phosphinc, mpbcnyl St~DC ant dcmra~cs of phosphorus, a~c ;uld ~nomony, with dlc praviso tbat ~e t~l d~dc wo 93/1~12~ Pcr/~ss2/l 1031 7 .~ 1 charge contributed to MP results in a net residual positive charge of q to the complex;
q is an integer having a value of I or 2, the residual charge of the complex cation;
S Y is a halogen-containing complex anion selected from BF4-, AsF6-, PF6-, SbF50H-, SbF6-, and CF3S03-; and n is an integer having a value of 1 or 2, the number of complex anions required to neutralize the charge q on the complex cation;
Examples of suitable salts of organometallic complex cations useful in 10 the composition of the invention include the (eta6-benzene)(etaS-cyclopentadienyl)i~on(1 +) hexafluoroantimonate (eta6-toluene)(eta5-cyclopentadienyl~iron(l +) hexafluoroarsenate (eta6-cumene)(eta5-cyclopentadienyl)iron(l+) hexafluorophosphate (eta6-~xylene)(eta5-cydopentadienyl)iron(l +) hexafluoroantimonate (eta6-xylenes(mixed isomers))(eta5-cyclopentadienyl) iron (1+) hexafluoroantinomate (eta6-xylenes(mixed isomers)~(eta5-cyclopentadienyl) iron (1 +) hexafluorophosphate ~eta6-o-%ylene)(eta5-cyclopentadienyl)iron( 1 + ) triflate (eta6-m-xylene)(eta5-cyclopentadienyl)iFon(1~) tetrafluoroborate ~eta6-mesitylene)(~taS-cyclopentadietlyl)iron(1 ~) hexafluor~antimonate (eta6-hexamethylbenzene)(etaS~yclopentadienyl)iron(l +) pentafluorohydr~xyantimonate (eta6-naphthalene)(etaS-cyclopentadienyl)iron(1 +) tetrafluoroborate (eta6-pyrene)(eta5-cyclopentadienyl~iron(l +) triflate (eta6-toluene)(eta5-cyclopentadienyl~iron(1 +) hexafluoroantimonate (eta6~umene)(eta5-cyclopentadienyl)iron(l + ) hexafluoroantimonate (eta6-~xylene)(eta5-cyclopentadienyl)iron( 1 ~ ) hexafluoroantimonate (eta6-m-xylene)(eta5-cyclopentadienyl)iron(l ~) hexafluoroantimonate (eta6-hexamethylbenzene)(eta5-cyclopentadienyl)iron(1 +) hexafluoroantimonate (eta6-naphthalene)(eta5-cyclopentadienyl)iron ( 1 + ) hexafluoroantimonate ~0 93/1~125 PCI/l,S92tllO31 212S7~i (eta6-pyrene)(eta5-cyclopentadienyl)iron(l +) hexafluor~antimonate (eta6-chrysene)~eta5-cyclopentadienyl)iron(l +) hexafluoroantimonate (eta6-perylene)(eta5-cyclopentadienyl)iron( 1 ~ ) hexafluoroantimonate (eta6-chrysene)(eta5-cyclopentadienyl)iron(l +) S pentafluorohydroxyantinionate (eta6-acetophenone)(etaS-methylcyclopentadienyl)iron(l +) hexafluoroantimonate (eta6-fluorene)(eta5-cyclopentadienyl)iron(1 +) hexafluor~antimonate Examples of preferred salts of organometallic complex cations useful in 10 the composition of the invention include one or more of the fo]lowing:
(eta6-xylenes(mixed isomers))(etaS~yclopentadienyl) iron (1 +) hexafluoroantinomate (eta6-xylenes(mixed isomers))(eta5-cyclopentadienyl) iron (1 +) hexafluorophosphate (eta6-m-xylene)(eta5~ycloperltadierlyl)iron(1 +) te~afluor~borate (eta6~xylene)(eta5~yclo~entadîenyl)iron(1 ~) hexafluor~antimonate (eta6-~xylenes)(etaS~yclopentadienyl)i~on(l +) triflate (eta6-toluene)(eta~yclopentadie~yl)iron(l~) hexafluoroantimonate (eta6-cumene)(etaS-eyclopentadiellyl)iron(l+) hexafluoroantimonate (eta6-p-xylene)(eta~yclopentadienyl)iron~l ~) hexafluoloantimonate (eta6 m-xylene)(eta5~yclopen~dienyl~iron(1 +) hexafluoroantimonate (eta6-hexamethylbenzene)(eta5-cyclopentadienyl)iron(l ~) hexafluoroantimonate (eta6-naphthalene)(etaS-cyclopentadienyl)iron( 1 + ) hexafluoroantimonate (eta6-pyrene)(eta5-cyclopentadienyl)iron~l+) hexafluoroantimonate (eta6-chrysene)(eta5-cycl~pentadienyl)ir~n(l +) hexafluoroantimonate (eta6-mesi~lene)(eta5-cyclopentadienyl)iron(l +) he~afluoro~timonate (eta6~umene~(eta5-cyclopentadienyl)iron(l +~ hexafluorophosphate (eta6-mesi~lene)(etaS-cyclopentadienyl)iron(l +) pentafluorohydroxyantimonate (eta6-toluene)(eta5-cyclopentadienyl)iron(l ~) hexafluoroarsenate wo 93/1~125 Pcr/~S92/1 lo31 2'~6~S1 - 12-In general, the thermally decomposable ester reaction products of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of ~he organometallic complex salt useful in the invention (hereinafter for brevity also referred to as "ester reaction products") are 5 soluble compounds that upon heating, prcferably to a temperature of 100C or more, decompose to release the chelating acid. Since the relcased acid forms a nonionizing chelation complex with the mctal atom, the chelation reaction tends to remove metal atoms from a solution of the photolyzod cationic organometallic salt. Thercupon, the acid of the salt anion is released for 10 ~eaction to caStalyze polymc~ization of the polymcnzable material in the systcm.
Thc cstcr reaction products are prepared from tertiary alkyl alcohols and any tcrdary allcyl alcohol that forms an estcr rcaction product with an appropriate acid~may be used. Examples of suitablc tcrtiaty alkyl alcohols are 15 t-but~nol, l,l~imethylpropanol, 1-methyl-2-ethylpropanol, 1, I~imethyl-n-butanol, 1,1-dimethyl-n-pentanol, 1, I-dimethylisobutanQl, 1,1,2,2-tetramethylpropanol, I-methylcyclopcntanol, l-methylcyclohe~anol, 1,l-dimethyl-n-hexanol, 1,1-dimethyl-n-octanol, 1,l-diphenylethanol, alld l,l-dibenzyl ethanol.
Chelaffng acids for inclusion in acid generating esters of the invendon are oxalic, phosphoric and phosphorous acids. Other illustrative cheladng acids that are useful include, polycarboxylic acids, for example, malonic, succinic, fumaric~ maleic, citraconic, aconitic, o-phthalic, trimesic acids and other polycarboxylic acids having less than 3 carbon atoms separating the 25 carboxylic groups; hydroxycarboxylic acids, for example, glycolic, lactic, beta-hydroxybutyric, gamma-hydroxybutyric, tar~onic, malic, oxalacetic, tartaric, and citric acids; aldehydic and ketonic acids, for example, glyoxylic,pyruvic, and acetoacetic acids; other acids of phosphorus; chromic acids; and vanadic acid.
The acid-gencrating esters may be prepared by procedures well known in the art. For example, acid-generating esters that incorporate the organic acids may be prepared by procedures described by Karabatsos et al. J. Org.

~'0 93/1~125 PCr/~S9~
;~` 21~675~L

Chem. 30, 689 (1965). Esters that incorporate phosphate, phosphonate and phosphite esters can be prepared by procedures described by Cox, Jr. J. Am.
Chem. Soc'y 80, 5441 (1958); Goldwhite J. Am. Chem. Soc'y 79, 2409 (1957); and Cox, Jr. J. Or~. Chem. 54, 2600 (1969), respectively.
S The acid-generating ester should be relatively nonhydrolyzable and is essentially free of acid. To remove traces of acid from the acid-generating ester, it may be passed through a column filled with an ion exchange resin.
Depending on the nature of the olefin that is formed from the acid-generating ester that is used, blown or solid polymerization products may 10 be obtained. Generally, solid, unfoamed polymerization products are obtained when the olefin formed has a boiling point of at least about 70C and preferably at least 100C at atmospheric pressure, while blown or foamed polymerization products are obtained when the olefin formed has a boiling point of less than about 70C. Acid-generating esters derived from tertia~y lS alcohols having 6 or more carbon atoms generally give olefins having a boiling point of at least 70C, and tertiary alcohols having 9 or more carbon atoms generally give olefins ha~ring a boiiling point of at least about 100C.
Th~ preferred ester reaction product is oxalate, phosphate, phosphinate, and phosphonate.
Also useful in accelerating the cationic polymerization when used in combination with the cationic organometallic photocatalyst and the acid-generating ester are peroxides: acyl peroxides such as benzoyl peroxide; aL~cyl peroxides such as t-butyl peroxide; hydroper~xides such as cumyl hydroperoxide; peresters such as t-butyl perbenzoate; dialkyl 25 peroxydicarbonates such as di(sec-butyl)peroxydicarbonate; diperoxyketals;
and ketone peroxides such as methylethylketone peroxide.
~ e optional additional free radical initiators can be selected from those compounds which generate free radicals upon exposure to heat or ~adiation, e.g., those compounds disclosed in "Mechanism of the 30 Photodecomposition of Initiatorsn, G. F. Vesley, Journal of Radiation Curin~,January, 1986, incoIporated herein by reference. They are selected from ~0 93/15125 PCr~l S92/1 ~031 2126~ 14 -acetophenones and ketals, benzophenones, aryl glyoxalates, acylphosphine oxides, sulfonium and iodonium salts, diazonium salts, and peroxides.
Preferred additional free radical initiators that are light activated are those that have an absorption maximum in the 300 to 400 nm region of the 5 electromagnelic spectrum.
Espocially uscful are acetophenones and ketals, described in U.S.
Patent No. 4,318,791 and incolporated herein by reference. Examples of preferred acetophenones and ketals useful in compositions of thc present invention include, but are not limited to the following:
2,2 dimethw~yacetophenone 2,2-dimethoxy-2-phenylacetophenone 2,2~icthoxyacetophenone 2,2~ibutoxyacetophenone 2,2~ihexoxyacetophenone 2,2-di(2-ethylhexoxypcetophenone 2,2~iphenoxyacetophenone 2,2 ditolyloxyacctophcnone 2,2-di(chlorophenyl)acetophenone 2,2-di(nitrophenyl)acetophenone 2,2-diphenoxy-2-phenylacetophenone 2,2-dimethoxy-2-methylacetophenone 2,2-dipropoxy-2-hexylacetophenone 2,2-diphenoxy-2-ethylacetophenone 2 ,2-dimethoxy-2~yclopentylacetophenone 2,2~i~2-ethylhexyl)-2-cyclopentylacetophenone 2 ,2-diphenoxy-2-cyclopentyl-acetophenone 2,2~i(nitrophenoxy)-2-cyclohexylacetophenone 2,2-dimethyl-2-hydroxyacetophenone 2 ,2~iethoxy-2-phenylacetophenone 2,2~iphenethyloxy-2-phenylacetophenone 2,2-(2-butenediyloxy)-2-phenylacetophenone 2,2-dimethyl-2-morpholino-(~thiomethyl)acetophenone wo 93/1~12~ Pcr/~S92~1 1031 21 26 7S l l-hydroxycyclohexyl phenyl ketone.
Also preferred are aromatic onium salts. These salts are disclosed, for example, in U.S. Patent Nos. 4,069,054, 4,231,951 and 4,250,203. The preferred aromatic halonium salts include, but are not limited to diazonium, S iodonium, and sulfonium salts, more preferably selected from diphenyliodonium, triphcnylsulfonium and phenylthiophenyl diphenylsulphonium salts of hexafluorophosphate, hexafluoroantimonate, riflate, hexafluoroarsenate, hydroxypentafluoroantimonate and tet~afluoroborate.
Photoinitiators that are useful for par~ally polymerizing alkyl acrylate monomcr without aosslir~ng, to prcpare the above-idendfied syrup, include thc bcnzoin cthcrs, such as benzoin methyl ether or benzoin isopropyl ether, substituted bcnzoin ethers, such as anisoin methyl ether, substituted acctophcnones,~such as 2,2- diethoxyacetophenonc and 15 2,2-dimcthoxy-2-phenylacetophenone, substituted alpha-ketols, such as 2-methyl-2-hydroxypropiophenone, aromatic sulfonyl chlorides, such as 2-naphthalene-sulfonyl chloride, and photoactivc oximes, such as l-phcnyl-l,l-propanedione-2(o-ethoxycarbonyl)oxim~. They may be used in amounts, which as dissolved provide about 0.001 to 0.5 percent by weight of 20 the alkyl acrylate monomer, preferably at least 0.01 percent.
The catalyst system should be presen~ in an amount effective to produce polyme~ization with the application of energy. Generally, the catalyst system can be present in the range of 0.01 to 20, preferably 0.1 to 10 weigh~ percent of the total curable composition. The ratio of 25 organometallic complex salt to thermally decomposable ester reaction product of a tertiary aLkyl alcohol and an acid is typically in the range of 100:1 to 1:100 of the catalyst system. Preferably, the ratio is in the range of 10:1 to 1:10. The ratio of the organometallic complex salt/ester reaction pJoduct mixture to free ~adical initiator, if present, is generally in the range30 of 1:100 to 100:1. PreferaUy, the ratio is in thc ~ange of 1:10 and 10:1.
In general, optional buffer compounds that may be used in some catalyst combinations of the invention to achieve a balance between latency WO 93/1~125 PCI'/I S92/1 1031 ?,~.? ~ 5~ 16 - ~
and reactivity are basic compounds having a solubility in the whole composition of at least about 1 part by weight per 1000 parts by weight of the whole composition. For example, salts that behave as buffers are salts of carboxylic acids, sulfonic acid or phosphoric acid.
It is also within the scope of this invention to add mono- or polyfunctiona1 alcohols to thc curablt composition. Suitable examples alcohols include but are not limited to methanol, ethanol, l-propanol, 2-propanol, l-butanol, I-pentanol, l-hexanol, l-heptanol, l-oct~nol, pcntaerythritol, 1 ,2-propanediol, ethylene glyc!, 1 ,4-butanediol, 1,5-pentanediol, I,~hcxanediol, 1,4-cyclohcxane dimcthanol, 1,4-cyclohexanediol and glycerol.
Prefcrably, compounds containing hydroxyl groups, particularly compounds containing from about 2 to 50 hydroxyl groups and above all, compounds having a weight average molecular weight of from about 50 to 25,000, preferably from about 50 to 2,000, for example, polyesters, polycthers, poly~ ers, polyacetals, polycarbonates, poly(meth)acrylates, and polyestcr amides, containing at least 2, galerally from about 2 to 8, but prefcrably from about 2 to 4 hydroxyl groups, or even hydroxyl-containing prepolymers of these compounds, are representatives compounds useful in 20 accordance with the present invendon and are described, for example, in Saunders, Hi~h Polymers. Vol. XVI, "Polyurethanes, Chemistry and Technology," Vol. I, pages 32-42, 44-54 and Vol. II, pages 5-6, 198-99 (1962, 1964), and in Kunststoff-Handbuch, Vol. VII, pages 45-71 (1966). It is, of course, p~missible to use mixtures of the above-mentioned compounds 25 containing at least two hydroxyl groups and having a molecular weight of from about 50 to 50,000 for example, mixtures of polyethers and polyesters.
In some cases, it is particularly advantageous to combine low-melting and high-melting polyhydroxyl containing compounds with one another (German Offenlegungsscl~ift No. 2,706,297).
Low molecular wdght compounds containing at least t~,vo reactive hydroxyl gropups (molecular weight from about 50 to 400) suitable for use in accordance with the present invention are compounds preferably wo 93~15125 Pcr/-S92~1 lo3 - 17~ b'751 containing hydroxyl groups and generally containing from about 2 tO 8, preferably from about 2 to 4 reactive hydroxyl groups. It is also possible to use mixtures of different compounds containing at least two hydroxyl groups and having a molecular weight in the range of from about 50 to 400.
5 Examples of such compounds are ethylene glycol, 1,2- and 1,3-propylene glycol, 1,4- and 2,3-butylene glycol, 1,5-pentanediol, l,~hexanediol, l,~octanediol, noopentyl glycol, 1,4-cyclohexanc dimcthanol, 1,4-cyclohexanediol, trimethylolpropane, 1,4-bis- hydroxymethyl cyclohexane, 2-mcthyl-1,3-propanediol, dibromobutenediol (U.S. Patent No. 3,723,392 10 (Konig et al.), glycerol, trimethylolpropane, 1,2,~hexanetriol, trimcthylolethane, pentaerythritol, quinitol, mannitol, sorbitol, diethylene glycol, tricthylcne glycol, tctracthylcne glycol, higha poiyethylene glycols, dipropylene glycol, higha polypropylene glycols, dibutylene glycol, higher polybutylcnc glycols, 4,4'-dihydroxy diphcnyl propanc and dihydroxy methyl 15 hydroquinone.
Othcr polyols suitablc for the purposes of the present invendon are the mix~res of hydroxy aldehydes and hydroxy Icetones (~formose") or the polyhydric alcohols obtained thaefrom by rcducdon (~formitoI") which are formed in thc autocondensation of fonnaldehyde hydrate in the prescnce of 20 metal compounds as catalysts and compounds capable of enediol formation as co~atalysts (German Offenlegungsschrift Nos. 2,639,084, 2,714,084, 2,714,104, 2,721,186, 2,738,154 and 2,738,512).
It is contemplated that polyfunctional aloohols such as carbowaxes poly(ethylene glycol), poly(ethylene glycol methyl ether), poly(ethylene 25 glycol) tetrahydrofurfuryl ether, poly(propylene glycol) may also be used in the compositions of the present invention.
It is also within the scope of this invention to add optional adjuvants such as thixotropic agents; plasticizers; toughening agents such as those taught in U.S. Patent No. 4,846,905 (Tarbutton et al.); pigments; fillers;
30 abrasive granules, stabilizers, light stabilizers, antioxidants, flow agents, bodying agents, flatting agents, colo~nts, binders, blowing agents, fungicides, bactericides, surfactants; glass and ceramic beads; and ~0 93/1:~125 PCl ~S92/1 1031 ~,~,?.6~

reinforcing materials, such as woven and nonwoven webs of organic and inorganic fibers, such as polyester, polyimide, glass fibers and ceramic fi?bers; and other additives as known to those skilled in the art can be added lo the compositions of this invention. Thcse can bc added in an amount S effective for their intended purpose; typically, amounts up to about 2S parts of adjuvant per total wcight of formulation can ?bc used. They can modify the properties of the basic composition to obtain a desired effect. They can be reacdve components such as materials containing reactive hydroxyl functionality. They can be also substantially unreactive, such as fillers both 10 inorganic and organic.
Optionally, it is within thc scopc of this invcntion to include photoscnsitizers or photoaccelators in thc radiation-sensitiw composidons.
Usc of photoscnsitizcrs or photoaccelerators alters the wavclength scnsitivity of radiation-sensitivc compositions employing the latent catalysts of this 15 invention. This is particularly advantageous when the latent catalyst does not strongly absorb the incident radiation. Usc of a photosensitizcr or photoaccelerator increases the radiation sensitiviq allowing shorter cxposure times and/or use of less pow~rful sources of radiation. Any photosensitizer or photoaccelerator may be uscful if its tdplet energy is at least 45 20 kilocalodes per mole. Examples of such photosensitizcrs are given in Table 2-1 of the reference, S. L. Murov, Handbook of Photochemistrv, Marcel Dekker Inc., N.Y., 27-35 (1973), and include pyrene, fluoranthrene, xanthone, thioxanthone, benzophenone, acetophenone, benzil, benzoin and ethas of benzoin, chrysene, p-terphenyl, acenaphthene, naphthalene, 25 phenanthrene, biphenyl, substituted derivatives of the preceding compounds, and the like. When present, the amount of photosensitizer of photoaccelerator used int the practice of the present invention is generally in the range of 0.01 to 10 parts, and preferably 0.1 to 1.0 parts, by weight of photosensitizer or photoaccelerator per part of organometallic salt.
Compositions of this invention are uscful for coatings, foams, shaped articles, adhesives, filled or reinforced composites, abrasives, caulking and sealing compounds, casting and molding compounds, potting and WO 93/151~:~ PCr/~S92/1 1031 ., 2I~751, encapsulated compounds, impregnating and coating compounds, and otha applications which are known to those skilled in the art. Compositions of this invention may bc used in the production of articles useful in the graphic arts such as printing plates and printed circuits. Methods of producing 5 printing platcs and printed circuits from photopolymerizing compositions are wcll known in the art (see for example British Patent Specification No.
1,495,746).
Glass microbubUes having an average diametcr of 10 to 200 micrometers can bc blended with polymerizable compositions of this 10 invention as taught in U.S. Patent No. 4,223,067 (Levens). If the microbubbles compdse 20 to 65 volume percent of the pressure-sensitive adhesivc, the polymaizcd product will have a foam-like appearance and be suitable for uses to which foam-backed pressure-sensitive adhesive tapes are useful.
Conducting particles, as taught in U.S. Patent No. 4,606,962 (Reylek et al.) can be blended with the polymerizable compositions of this invendon.
Thc conducting particles, such as metal coated particles, or metal flakes, added to the polymerizable compositions of this invendon can provide electrical conduction between semiconductor chips and circuit traces.
20 Advantageously, such a conducting adhesive- layer eliminates solder and provides better mechanical strength. Purthermore, more connections per area (pitch) can be realiæd using a conducting adhesive. ~he elimination of solder is environmentally safer, in that hazardous solvents and lead from solder are eliminated.
Other materials that can be blended with the polymerizable compositions of this invention include tackifiers, reinforcing agents, and other modifiers, some of which may copolymeriæ with the free radically or cationically polymerizable monomers or photopolymeriæ independently.
However, the addition of any such material adds complexity and hence 30 expense ~ an otherwise simple, straightforward, economical process and is not preferred except to achieve specific results. Preformed polymers useful as film formers include for example, polymethacrylate, polystryene, , wo 93/15125 PCI /~S92/1 1031 ., , .~
S~ 20-poly(vinylacetate), poly(butadiene), polybutylacrylate, poly(caprolactone), polycarbonate, poly(dimethylsiloxane), poly(ethylene oxide), poly(isoprene), poly(isobutylene), poly(alpha-methylstyrene), poly(vinyl chloride), polyvinylpyrrolidone .
S While it is preferred that solvents are not used in preparing the polymerizabk composidons of the present invention, solvents, preferably organic, can be used to assist in dissolution of the catalyst system in the freeradically and cationically polymerizable monomers. lt may be advantageous to prepare a concentrated solution of the organometallic complex salt in a 10 solvcnt to simplify the preparation of thc polymcrizablc composition.
Rcpresentative solvcnts includc acctone, methyl-cthyl-kctone, cyclopcntanone, mcthyl ccllosolvc acctatc, methylenc chloride, nitromethane, methyl formate, gamma-butyrolactone, and 1,2-dimethoxyethane (glyme).
In some applications, it may be advantageous to adsorb the catalyst 15 systcm onto an inert support such as silica, alumina, clays, etc., as described in U.S. Patent No. 4,677,137 (Bany et al.).
The present invention also provides a process for preparing epoxy-acrylate mateIials, comprising thc s~ps of:
(1) providing a substrate, (2) coating a polymerizable composition as described above compnsing:
(a) at least one ~ree radically polymerizable monomer;
(b) at least one cationically polymerizable monomer;
(c) a catalyst system comprising:
(i) at least one organometallic complex salt, (ii) a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, and (iii) optionally, peroxide, and (iv) optionally, at least one free radical initiator;
(d) optionally, a buffer compound; and (e? optionally, a mono- or polyfunctional alcohol, ~vo 93~1~125 2 1 ~ ~ 7 5 :. Pcr/~ S92/l 103l to the substrate by methods known in the art, such as bar, knife, reverse roll, knurled roll, or spin coatings, or by spraying, brushing, and the like, with or without a coating solvent, and (3) evaporating solvent, if present, (4) applying energy to the article to cause the polymerization of the coating, preferably utilizing a technique called the "multi-co!or photoinitiation process," such that the polymerized composition is sequentially or simultaneously irradiated with light sources that provide radiation of substantially different wavelengths.
A process for the polymerization of the epoxy-acrylate thermoset resins (also referred to as "thermoset resin" or "resin compositionn) composition may be carried out all at once or in a stepwise fashion. The resin composition comprises an acrylate syrup, that is a mixture of partially polymerized free radical monomers ( 0.0 to 15.0% conversion); substantially 15 unpolymerized epoxy monomers; and optional adjuvants. HAcrylate syrupU
as used in this application means a composition comprising a partially polymerized mixture of acrylates only or a partially polymerized mixture of acrylates al~d unpolymerized epoxy monomers.
Method A
A first step in the preparation of the acrylate syrup is to mix the polymenzable monomers (ca~onically and free radically polyme~izable monomers~ with a catalytically effective arnount of a free radical initiator.
Preferably, the free radical initiator is not a crosslinking agent and is generally present in an amount within the range of 0.01 to 10.0% by weight of the polymerizable composition, preferably in the range of 0.02 to 1.0%
by weight of the polymerizable composition.
The second step is to apply energy to the polymeri~able composition and allowing it to polymerize such that the viscosity is increased to within a range of 0.3 to 20.0 Pascal seconds (Pa s) at ambient temperature.
30 Preferably, the viscosity after this step is in the range of 0.5 to 2.0 Pa-s.The increased viscosity provides an acrylate syrup that is a more suitable coating composition for the production of the articles of the invention. The ~0 93/1:~12~ PCl /~S92/1 1031 2'126~151 polymerizable composition may be polymerized using any well-known thermal polymerization techniques and quenched with air to attain the desired viscosity. Preferably, the free radic~ initiator is a photoinitiator, and the partial polymerization may be stopped at any point by eliminadng the 5 irradiation source.
A third step is to mix at least one organometallic complex salt and any optional bireactive free radically polymaizable monoma, bifunctional monomer, adjuvants and additional amount of the above-identified free radical initiator into thc acrylate syrup.
A fourth stcp is to degas the curabk compositions under vacuum to remove bubbles and dissolved oxygen. Although it is preferable to do this step just prior to co~ting, it may be carried out at any time from a few hours to several weeks prior to coatdng. To insure stability of the degassed curable compositions, it is preferable to keep them from unwanted exposure to light.
15 ~d B
Altcrnatively, if the free radically polymeriz~ble composition is derived from a mixture of onc or morc alkyl (meth)acrylates, an acrylate syrup of the free radically polymerizable monomers can be p~d without ~e addition of cationically polymerizable monomers.
The first step in the alternative method is to mix the free radically polyme~izable monomers with a catalyhcally effecdve amount of a free radical inidator. Preferably, this free radical initiator is not a crosslinking agent and generally is present the amounts in the range of 0.01 to 10.0% by weight of the free radically polymerizable components, and preferably in the range of 0.02 to 1.0% by weight.
The sesond step is to apply energy to the polymerizable composition and allow it to polymerize such that the viscosity is increased to within a range of 0.3 to 20.0 Pa-s at ambient temperature. Preferably, the viscosity afte~ this step is in the range of 0.5 to 2.0 Pa-s. The increased vissosity 30 provides a syrup that is a more suitable coating composition for the production of the ar~ticles of the invention.

WO 93/15125 PCI/~`S92/1 1031 . 2126751 The polymerizable composition can be polymerized by any well-known thermal polymerization techniques and quenched with air to attain the desired viscosity. It is preferable to use a photoinitiator as the free radical initiator in this process, such that the partial polymerization may be 5 stoppeid at any point by eliminadng the irradiadon source and then quenching polymerization with oxygen. It is preferable to use a low intensity i~radiation source in this photochemical process and that the mixture be cooled during irradiatdon. Low intensity irradiation and cooling minimize gel formation during the syrup making process. After quenching the 10 polymcrization, opdonal bireactive monomers, bifunctiona1 monomers, adjuvants and additional free radical initiators may be added.
The cationic initdator is then added to a cadonically polymerizable material. If the cationic inidator is not readily soluble, dissoludon can be aided by the application of heat. When heating the cadonic inidator in the 15 presence of the cadonically polymerizable material, it is advantageous to reduce its exposure to light, thus minimizing the risk of unwanted polymerization. The cadonic initiator can also be dissolved in a suitable solvent first and then added to the cadonically polymerizable material.
It is also permissible to add the optional bireactive monomers, 20 bifunctional monomers, adjuvants and additional free radical inidators to this composition.
The acrylate syrup and cationically polymerizable mixture are then mixed together. While it is permissible to mix the components in any order, it is preferable to add the ~crylate syrup to the cationically polymerizable 25 mixture. If optional bireactive monomers, bifunctional monomers, adjuvants and additional free radical initiators have not been added previously, they may be added at this time. The composition is thoroughly mixed to provide an even distribution of material.
The curable compositions are degassed under vacuum to remove 30 bubbles and dissolved oxygen. While it is preferable to do this step just prior to coating, it can be carried out at any time from a few hours to WO 93/1 ,12:~ PCr/~S92/1 1031 several weeks prior to coating. To msure stabllity of the degassed curable compositions, it is preferable to keep them from unwanted exposure to 1ight.
Method C
If the monomers are derived from the reaction product of S (meth)acrylic acid and alcohol containing a heteroatom, oxygen, nitrogen, or sulfur in the chain, that is, polar (meth)acrylates, the monomers tend to gel, becoming crosslinked dudng the next stage of the syrup-making process and therefore difficult to use in any subsequent process. This has generally made thesc types of monomcrs unsuitable for syrup manufacture. It was surprising l0 to find that the simplc addition of an alkyl (mcth)acrylatc or other addidvcsthat can bc broadly cbssified as chain transfcr agents reducc or eliminatc this tendency to form gds during the syrup-making prwess.
If, for example, an alkyl (meth)acrylate is used, then it can be~used in any rado with the polar acrylatc. The ratio can be selocted to control the 15 final physical properties of the cured composition. The ratios can vary from 99:1 to l:99, polar (meth)acrybtc:alkyl (me~h)acrylate. Generally, some intermediate ratio would be selectcd to optimize the contributions from the different monomcrs. The preferrcd range would be 80:20 to 20:80.
If, on the other hand, a chain transfer agent is used to inhibit gd 20 formation in the polar acrylates, then a ratio of chain transfer agent:polar acrylate would be 10:90 to 0.5:99 5, preferably 5:95 to 0.5:99.5~ Chain transfer agents useful in practicing the present invention are described in G.
Odian Principles of Polymenzation 253-59, at 252 (3d ed. 1991). Suitable chain transfer agents possess at least one abstractable hydrogen atom (that is, 25 hydrogen atoms attached to a carbon atom adjacent to a heteroatom, such as, O, N, S, or hydrogen atoms attached to a secondary or tertiary carbon atom) but do not possess a free radically polymerizable group For example, tetrahydrofuran (IHF) would be a suitable chain transfer agent, however, the (meth)acrylated THP would not be suitable A second step is to apply enagy to the polymerizaUe composition and allowing it to polymaize so that the viscosity is increased This will provide a acrylate syrup generally having a viscosity of 300 to 20,000 ~O 93/1~125 2 1 2 S 751 Pcr/~S92Jl 1031 centipoise at ordinary room temperature. Preferably, a suitable viscosity after this step is in the range of 500 to 2000 centipoise. The increased viscosity provides a composition that is more suitable coating composition for the p~oduction of the arddes of the invention.
This partial polymedzation process can be accomplished by convendonal thermal polymedzadon techniques and then quenched vith air to attain the desired viscosity. It is preferable to use a photoinitiator for this process, the partial polymerization may be stopped at any point simply be turning off the irradiation source and the polymerization can be quenched 10 with oxygen. It is preferable to use a low intensity irradiation sourcc in this photochemical process and that thc mixture be cooled during irradiation.
Low intensity irradiation and cooling minimize gel formation during the syrup malcing proccss. It is desirable to cool the composition to 10C or less to control any cxothcrm produced during the polymerization process.
After stopping the polymerization, optional bireactive monomers, bifunctional monomers, adjuvants and additional free radical initiators may be added.
The cationic organometallic is added to the cationically polymerizable material. If the cationic organometallic is not readily soluble, its dissolution20 can be aided by the application of heat. When heating the cationic organometallic in the presence of the cationically polymerizable material, it is advantageous to reduce its exposure to light. This will minimize the risk of unwanted polymenzation. The cationic organometallic can also be dissolved in a suitable solvent first and then added to the cationically 25 polymerizable material. It is also possible to add the optional bireactive monomers, bifunctional monomers, adjuvants and additional free radical initiators to this composition.
The acrylate syrup and cationically polymerizable mixture are mixed.
While it is possible to mix the components in any order, it is preferred to 30 add the acrylate SyNp to the cationically polymerizaUe mixture. If the optional bireactive monomers, bifunctional monomers, adjuvants and additional free radical initiators have not been added previously, they can be ~0 93/1~12~ PCl/~Sg2/1 1031 2~26~s~

added at this time. The composition is thoroughly mixed to provide an even distribution of material.
The curable compositions are degassed under vacuum. This helps to remove bubbles and dissolved oxygen. While it is preferable to do this step 5 just prior to coating, it can be carried any time from a few hours to days even weeks before Ihe actual coating. To keep these curable compositions stable, it is preferable to keep them from unwanted exposure to light.
The syrup from Methods (A), (B), or (C) may be coated onto a backing member and exposed to energy to complete the polymerization. The lO preferred method is by sequential exposure to irradiation of substantially different wavelengths to complete the polymerization, said process being called the "multi-color photoinidation process."
Temperature of polymerizadon and amount of catalyst will vary and be dependent on~the particular curable composition used and the desired 15 application of the polymerized or cured product. The amount of curing agent to be used in this invendon should be sufficient to effect polymerization of the polymerizable mixtures (that is, a catalytically-effectiveamount) under the desired use conditiol.s. Such amount generally will be in the range of about O.Ol to 20 weight percent, and preferaUy O. l to lO.0 20 weight percent, based on the weight of curable composition.
For those compositions of the invendon that are radiation- sensitive, composidons containing an organornetallic complex salt of Formula I and, optionally, a free radiGIl photoinitiator, any source of radiation including electron beam radiation, gamma radiation, and radiation sources emitdng 25 acdve radiation in the ultraviolet and visible region of the spect~um (e.g., about 200 to 800 nm) can be used. Suitable sources of radiation include mercury vapor discharge lamps, carbon arcs, tungsten lamps, xenon lamps, lasers, sunlight, etc. The required amount of exposure to effect polymenzation is dependent upon such factors as the identity and 30 concentrations of the organometallic complex salt and optional free radical photoinitiator, the particular free radically and cationically polymerizable WO 93/151~5 PCl`/~S92/1 1031 21%6751 monomers, the thickness of the exposed material, type of substrate, intensity of the radiation source and amount of heat associated with the radiation.
For the multi-color photoinitiation process, light of various wavelengths can be provided in a number of ways. Different light sources S of substantially different wavelengths can be used. The wavelengths of major iatensity for each light sourcc can be obtained from tne examination of the spectral output of each sourcc. One light source could be used for different wavelength regions through the use of filters or monochromators.
Lasers or othcr monochromatic light sourccs would be useful. For example, 10 a tungsten lamp, whosc output is mainly in the visible region, could be used as onc light sourcc while a lamp liloc the Sylvania 40 watt F-40/350BI, whosc output is concentratcd around 360 nm, could be used as another source.
Irradiation sources that provide light in the region from 2ao to sao 15 nm arc cffectivc in thc practicc of this invention. A preferred region is bctween 250 to 7a0 nm. It is prcferred to usc a combination of wavelengths such as 250 to 400 nm for the ultraviolet and 350 to 7ao nm for the visiblc, eithcr sequcndally or simultaneously or in muldple steps. lt is most prcfcrred to irradiate, first in thc region wherc the catalyst system of the 20 minor polymerizablc component absorbs, followed by radiation in the rcgion wherein the catalyst system of the major polymerizable component absorbs.
Thermal polymerization using direct heating or infrared electromagnetic radiation, as is known in the art, can be used to cure the free radically and ca~ionically polymerizable monomers according to the 25 teachings of this invention. It is also possible to use microwave irradiation to provide energy to cure the compositions of this invention.
It is within the scope of this invention to include multi-stage curing by first acdvating the curing system by irradlating the curable compositions sequentially or simultaneously with radiation of substantially different 30 wavelengths. In addition, it may be desirable to subsequently [after the imdiation stép(s)l thermally cure the activated precursor so obtained, the irradiation temperatures being below the temperature employed for WO 93/15123 PCT/~S92/1 1031 ,G~S~ 28-subsequent heat-curing. These activated precursors may normally be cured at temperatures which are substantially lower than those required for the direct thermal curing, with an advantage in the range from 50 to 110C.
This multi-stage curing also makes it possible to control the polymerization S in a particularly simple and advantageous manner.
It is often advantageous to protect the curable composition from premature exposure to light. This prevents the premature photoinitiation of polymerization. This can be accomplished by working under lights that do not activate thc composition, such as darkroom safelights. Or it is possible 10 to work under low intensity visible light for short periods of time without ddetaious effect. Vessels in which the curable compositions are stored can be placed within light tight containers. It is even possible to work under ordinary room fluorescent lights for brief periods wi~out any harm.
In the currcnt state of the art, photopolymerization is carried out in 15 an inert atmosphere. Any inert atmosphere such as nitrogen, carbon dioxide, helium or argon is suitable. A su*iciently inert atmosphere can be achieved by covering a layer of the photoactive mixture with a plastic film which is transparent to ultraviolet radiation and irradiating through that film in air.
Objects and advantages of this invention are further illustrated by the following examples, but the particular materials and amounts thereof recited in ~ese examples, as well as other conditions and details, should not be construed to unduly limit this invention.

~ O 93/1~125 2 1 2 6 7 ~ 1 PCr/~S92/t 1031 GLOSSARY

Epon 828 diglycidyl ether of bisphenol A (epoxy equivalent weight of 185-192 g/eq), (available from Shell Chemical Company);
Epon 1001F diglycidyl ether of bisphenol A (epoxy equivalent weight of 525-550 g/eq), (available from Shell Chemical Company);
0 DPL-862 diglycidyl ether of bisphenol F (epoxy equivalent weight of 16~177 g/eq), (available from Shell Chemical Company);
ERL~299 bis(3,4-epoxy-~methylcyclohexyl-methyl)adipate, (available from Union Carbide Colporation);
ERL-4221 3,4-epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, (available from Union Carbide Corporation);
DEN-439 epoxy novolac resin (epoxy e~uivalent weight of 191-210 g/eq), (available from Dow Chemical Company);
Quatrexl high purity liqu;d bisphenol A-based ~poxy resin (epoxy equivalent weight of 182-190 g/eq), ~available from Dow Chemical Company under trade designa~on "Quatrex 1010");
Quatrex2 high purity solid bisphenol A-based ~poxy resin (epoxy equivalent weight of 44~575 g/eq~7 (available from Dow Chemical Company under ~ade designation "Qua~ex 1410");
30 COM (eta6-xylenes)(etaS-cyclopentadienyl) i~n (l+) hexafluoroantimonate;
tBOX di-t-butyl oxalate, (available from Aldrich Chemical Company)~
35 bBOX di-benzyl-t-butyl oxalate, (prepared according to Karabatsos et al. J Or~. Chem. 30, 689 (1965)~;
CHDM 1,4-cyclohexane dimethanol, (available from Eastman Chemical Company);
Irgacure 261 Cp(Cum)Fe+PF~,-, (available from Ciba-Giegy Company);
KB 1 benzil dimethoxy ketal (2-phenyl-2,2'dimethoxyacetophenone~, (available from Sartomer Company under the trade designation of Esacure KB-l);

wo 93/1~l2~ Pcr/~ Ss2/ l 103 ,6~ 30-Cp(Mes)Fe~SbP6- (eta6-mesitylene)(eta5-cyclopentadienyl) iron (1 +) hexafluoroantimonate;
Cp(Mes)Fe+PF6- (eta6-mesitylene)(eta5-cyclopentadienyl) iron (1 +) hexafluorophosphate;
Cp(Mes)Fe+BF4- (eta6-xylenes)(eta5-cyclopentadienyl) iron (1 +) tetrafluoroborate;
IBA isobornyl acrylate (available from Sartorner Company under the trade designation SR-506);
A 2-tetrahydrofurfuryl acrylate, (available from Sartomer Company under the trade designation of SR-285);
15 HDDA 1,6-hexane diol diacrylate, (available from Sartomer Company under the trade designation SR-238);
BDDA 1 ,4-butane diol diacrylate, (available from Sartomer Company under the trade designation SR-213);
TEGDA tetraethylene glycol diacrylate, (available from Sartomer Company under the trade designation SR-268);
CHDM 1,4-cyclohexane dimethanol, (available from Eastman Chemical);
CHDO 1,4-cyclohexane diol, (available from Aldrich Chemical Company);
30 HDO l,~hexanediol, (available from Aldrich Chemical Company);
BDO 1,4-butanediol, (available from Aldrich Chemical Company);
EG 1,2-ethanediol, (available from Matheson, Coleman & Bell);
TMP trimethylol propane, (available from Aldrich Chemieal Compar y).

SAMPLE P~PARAT10N
Sample preparations for all examples were canied out-under subdued lights, that is, at a light intensity below the level necessary to initiate polymerization. Solutions were stored in amber glass bottles.

W093/15125 212~j i51 PCl/I_S92/11031 CURE I~ME EVALUATION PROCEDURE
Cure time evaluation using cationic organometallic salts and oxalate esters as photoinitiators for epoxy and epoxy-acrylate composidons were conducted in the following manner: Stock solutions were made containing 25 S grams of Epon 828 epoxy and 0.125 gram of the organometallic salt and/or 0.125 gram of the oxalate ester and/or 2.5 gram of the diol. Epoxy-acrylate stock solutions were made containing 20 grams of Epon 828, 5 grams of acrylate, O.OOS gram of K~l, 0.125 gram of the organometallic salt, Cp~Xyl)Fe ' SbP6-, and/or 0.125 gram of the oxalate ester, di-t-butyl oxalate 10 and/or 2.5 grams diol.
Approximately 0.3 gram of each slock solution was placed in individual aluminum containers to evaluate for cure times. light exposures wcre made using an appropdate light source and the samp!e was placed on a hot phte covered with a hrge aluminum phte to keep the temperature 15 constant at 90C. Cure time was determincd by touching the sample with a stick and noting when the sample was no longer liquid. Three evaluations per sample were completed and the average time to cure tack-free was recorded.

CURED POLYMER PHYSICAL PROPERTY MEASUREMENT PROCEDURE
Epoxy stock solutions were made containing 25 grams of epoxy and 0.125 gram of the organometallic salt~ Cp(Xyl)Fe~SbP6-, and/or 0.125 gr~m of the oxalate ester, tBOX and/or 2.5 gr~ns of diol. Epoxy-acrylate stock solutions were made containing 20 grams of Epon 828, 5 grams of acrylate, 0.005 gram of KB-l, 0.125 gram of the ~rganometallic salt, Cp(Xyl)Fe+SbF6-, andlor 0.125 gram of the oxalate ester, tBOX and/or 2.5 grams of diol.
Dogbone molds for sample curing were made by stamping a dogbone (ASTM D638 IV-89) out of a 7.5 cm by 15 cm silicone rubber sheet (~8702, 36" x 36" x 1/32n, 70 darometer, made by the Groendyk Manufactunng Company, Buchanan, VA). Samples were prepared for tesdng by pouring the 30 solution into the dogbone mold situated between two sheets of transparent polyester release liner. Dogbones were irradiated with the appropriate light source, fol1Owed by heat curing in an oven for 30 minutes at 100C. At least ~o 93/1~125 Pcrr/~S92/11031

6~ 32-three dogbones were measured from each sample series and the average reported.
Physical property measurement of cured epoxy and epoxy-acrylate compositions was conducted according to ASTM D638-89, "Standard Test 5 Method for Tensile Properties of Plastics" using an Instron, model ~l 122.

LIGHT EXPOSURE PROCEDURE
Quartz halogen lamp - A 500 watt tungsten halogen floodlight (#2V623 from Dayton Electrical Mfg. Co., Chicago, IL). Light exposures were made l0 with the sample positioned l5 cm under the light. Exposure was timed using a Gralab Timer (model #300, Dimco-Gray Company~ Centerville, OH).
BL-350 lamp - Two l5 Watt BL-350 fluorescent bulbs (JYF1ST8-BL~
General Electric Corporation, New York, NY) in a Blak-Ray Lamp fixture (model ~XX-lSL, UVP, Inc., San Gabriel, CA). Light exposures were made 15 with the sample positioned 8 cm under the light. Exposure was timed using a Gralab Timer (model #300, Dimco-Gray Company, Centerville, OH).

EXAMPLES 1-2 ~ND COMPAR~TIVE EXAMPLES Cl-C3 Epoxy Cure Time Trials These examples illustrate the use of the cationic organometallic salt photocatalyst, Cp(Xyl)Fe+SbF6~, with an oxalate ester. This combination was more efficient than the cationic organometallic salt alone, while continuing to provide good thermal stability in the dark. Two different oxalate eseers were tested, tBO~ and bBOX. Cure time trials were done in Epon 828 epoxy, 25 after two minutes ir~adiation with a quartz halogen Jamp. Examples C2 and C3 do not contain the cationic organometallic complex salt.

~0 93~1512~ PCr/~S92/1 1031 , 212~751 Table 1 Catalyst System Cure Time at 90C
EX # in Epon 828 (seconds) S Cl COM 329 1 COM:tBOX 41 2 COM:bBOX 236 C2 tBOX no cure after 8 hours C3 bBox no cure after 8 hours Essentially no cure took place when these samples were heated in the dark for 4 hours at 100C.

EX~MPLES 3-4 ~ND COMP~TIVE B~MPLES C4 C7 Epoxy Cure Time Trials These examples illustrate the use of the combination of the cationic organometallic salt with an oxalate ester and a diol. Many epoxies were too brittle to be used alone and were "flexibilized~ or chain extended with diols 20 and/or polyois. Addition of the diol, 1 ,4-cyclohexane dimethanol (CHDM), to the cationic organometallic salt resulted in increased cure times. In cont~ast, addition of the diol to the COM/oxalate ester catalyzed samples did not substan~ally affect cure times. Examples C6 and C7 did not contain the cationic organometallic complex salt.
Table 2 Catalyst System Cure Time at 90C
EX # in Epon 828 (seconds) ., .. ... ~ .

CS COM:CHDM 879 3COM:tBOX: CHDM 38 4 COM:bBOX:CHDM 269 C6 tBOX:CHDM no cure after 8 hours C7 bBOX:CHDM no cure after 8 hours 35 ~ssentially no cure took place when these samples were heated in the dark for four hours at 100C.

WO 93/1~,125 PCr/~592/1 1031 Sr~ 34 EXAMPLES 5-9 AND COMPARATIVE EXAMPLES Cg-C12 EPOXY Cure Time Trials These examples illustrate that the SbF6- salt of the cationic organometallic photocatalyst was reactive with the oxalate ester, di-t-butyl S oxalate, for catalyzing Epon 828 epoxy polymerization. Cure time trials were done as described above, after two minutes irradiation with a quartz halogen lamp.
Table 3 Catalyst System Cure Time at 90C
EX ~ in Epon 828 (seconds) C8 CpXylFe~SbF, 329 S CpXylPe+SbF6~:tBOX 41 C9 CpMesPe+SbF6~ > 10 minutes 6CpMesFe+SbP6~:tBOX 94 C10cpcumPe+PF6~ > 10 minutes 7CpCumFe+PF6~:tBOX > 10 minutes C11 CpMesFe~P~ > 10 minutes . 8CpMesFe~PF6~:tBOX > 10 minutes C12 CpMesFe~BFj > 10 minutes 9CpMesFe+BF4~:tBox ~10 minutes Essentially no cure took place when these samples were heated in the 25 dark for four hours at 100C.

EXAMPLES 10-13 AND COMPARAT~VE EXAMPLES C13-C16 Epoxy Cure Time Trials These examples illustrate that the SbF6- salt of the cationic 30 organometallic photocatalyst was reactive with the oxalate ester, di-t-butyl oxalate, for catalyzing ERL-4299 cycloaliphatic epoxy polymerization. Cure time trials were done as described above, after two minutes irradiation with a quartz halogen lamp.

~vo 93/1~12~ 212 ~ 75~l PCr/~592/11031 Table 4 Catalyst System Cure Time at 90C
EX ~ in ERL 4299 (seconds) C 13 Cp(Xyl)Pe+SbF6 59 Cp(Xyl)Fe~Sb~ tl3OX 38 C14 Cp(cum)Fe+pp6- > 10 minutes 11 Cp(Cum)Fe+PF6~:tBOX > 10 minutes C15 Cp(Mes)Fe~pF6 > 10 minutes 12 Cp(Mes)Fe+PF6~:tBOX > 10 minutes Cl6 Cp(Mes)Fe+BFi > 10 minutes 13 Cp(Mes)Fe+BF4~:tBOX > 10 minutes Essentially no cure took place when these samples were heated in the 15 dark for four hours at 100C.

EXAMP~FC 14-19 Epoxy Cure Time Trials These exarnples illustrate the use of various diols with the cationic 20 ~rganometallic photocatalyst, Cp(Xyl)Fe+SbP6~, and the oxalate ester, tBOX, for catalyzing Epon 828 epoxy polymerization. Cure time trials were done as descnbed above, a~ter tvvo minutes irradia~on ~th a quartz halogen lamp.

Table 5 Catalyst Sys~em Cure Time at 90C
EX # in Epon 828 (seconds) 14 COM:tBOX:CHDM 38 15 COM:tBOX:CHDO 107 16COM:tBOX:Ethylene Glycol > 10 minutes 17 COM:tBOX:HDO > 10 minutes 18 COM:tBOX:BDO ~ 10 minutes 19 COM:tBOX:TMP > 10 minutes Essentially no cure took place when these samples were heated in the dark for 4 hours at 100C.

~0 93/15125 . PCl/~S92/1 10~1 .S~5~ - 36-EXAMPLES 2~23 AND COMPAR~TIVE EXAMPLES C17-C20 Epoxy-Acrylate Cure Time Trials These examples illustrate the use of the cationic organometallic salt photocatalyst, Cp(Xyl)Fe~SbF6-, with tBOX, and a free radical photocatalyst, S benzil dimethoxy Icetal (ICB-l), to polymerize an epoxy-acrylate composition.
This combination was a more efficient photocatalyst system than the cationic organometallic salt alonc, while continuing to provide good thermal stability inthe dark. Samples were blanketed with a stream of nitrogen while irradiated for two minutes with a BL-350 low intensity UV lamp. After irradiation, cure 10 time trials were done as described above.

Table 6 Catalyst System Acrylate Cure Time at 90C
lS EX #in Epon 828 (80X) (20%) (soconds) ..
C17COM:KB 1 -lm A 323 20COM:tBOX:KB 1 THFA . 210 C18COM:KB 1 HDDACured under light*
21COM:tBOX:KB 1 HDDACured under light*
Cl9COM:KB 1 TEGDACured under light*
22COM:tBOX:KB 1 TEGDACured under light*
C20COM:KB 1 BDDACured under light*
23COM:tBOX:KB 1 BDDACured under light*
25 * sample cured to a non-tacky state while being irradiated.
Essentially no cure took place when these samples were heated in the dark for 4 hours at 100C.

Epoxy-Acrylate Cure Time Trials These examples illustrate the use of the combination of the cationic organometallic salt with an oxalate ester, a diol, and a free radical photoinitiator, benzil dimethoxy ketal (KB-l) The epoxies were too brittle to be used alone and were "flexibilized" or chain extended with diols and/or ~o 93/15125 212 6 7 S 1 Pcr/~ S92/l 1031 polyols. Addition of the diol, 1,4-cyclohexane dimethanol (CHDM), to the cationic organometallic salt resulted in increased cure times. In contrast, addition of the diol to the COM/oxalate ester catalyzed samples did not substantially affect cure times. Samples were blanketed with a stream of 5 nitrogen while irradiated for two minutes with a BL-350 low intensity UV
lamp. After irradiation, cure dme trials were done as described above.

Table 7 ~0 Catalyst System Acrylate Cure Time at 90C
EX # in Epon 828 (8096) (20%) (seconds) C21 COM:CHDM:KB 1 TH~A 40 24 COM:tBOX:CHDM:KB- 1 THFA 311 C22 COM:CHDM:K~l TEGDACured under light*
COM:tBOX:CHDM:KB-l TEDGACured under light*
C23 COM:CHDM:K~l BDDACured under light*
26 COM:tBOX:CHDM:KB-l BDDACured under light*
C24 COM:CHDM:KB 1 HDDACured under light*
1~ 27 COM:tBOX:CHDM:KB 1 HDDACured under light*
* sample cured to a non-tacky state while being irIadiated.
Essentially no cure took place when these samples were heated in the dark for four hours at 100C.

Epoxy Physical Property Measurements These examples illustrated the effect of combining the cationic organometallic photocatalyst with the oxalate ester on cured epoxy polymer physical properties. The polymer films that were more completely cured had 30 higher tensile strength and modulus (stiffness).

~o 93/1~125 PCrt~ 031 ,6 - 38 -Table 8 EX ~ Catalyst Epoxy S~rength Modulus System (MPa) (MPa) C25 COM Epon 828 7.2 184.4 28 COM:tBOX Epon 828 48.8 866.6 C26 COM ERL^4299 31.4 474.4 29 COM:tBOX ERL-4299 39.0 594.g C27 COM ERL~22 1 16 . 3 796. 9 - 30 COM: tBOX ERL-422 1 29 . 8 842 . 4 Essendally no cure took place when these samples were heated in the dark for four hours at 100C.
EXAMPT Fe 31-34 AND COMPARATIVE EXAMPLES C28-C3 1 Epoxy-Acrylate Physical Property Measurements These examples illus~ated the effect of combining the cationic organometallic photocatalyst with the oxalate ester on cured epoxy-acrylate 20 polymer physical properties. The polymer films that were more completely cured have higher tensile strength and modulus (sti~fness).

Table 9 ~ . . . . _ _ .
Catalyst Tensile EX ~ System in Acrylate Strength Modulus Epon 828 (80~) (20%) (MPa) (MPa) .. ~_ .
C28 COM:KB 1 HDDA 8.5 152.2 31 COM:tBOX:KB-l HDDA 21.4 384.5 C29 COM:KB 1 THFA 13.2 167.1 32 COM:tBOX:KB- I THFA 63 . 6 974 . 3 C30 COM:KB-1 BDDA 8.0 70.8 33 COM:tBOX:KB-l BDDA 27.7 612.4 C3 1 COM:KB 1 TEGDA 4.1 6. 8 34 COM : tBOX : KB- 1 TEGDA 11 . 0 11 5 . 2 WO 93/1:~12:~ PCr/~S92~1 1031 2 1 ~ S 7 5 1 EXAMPLES 35-38 AND COMPARATIVE ~MPLES C32 C35 Epoxy-Acrylate Physical Property Measurements These examples illustrated the effect of combining the cationic organometallic salt with an oxalate ester, a diol, and a free radical S photoinitiator, benzil dimethoxy ketal (KB 1) on cured epoxy-acrylate polymer physical properties. Addition of the diol to the COM/oxalate ester catalyzed samples increased cured tensile strength and modulus.

Table 10 Catalyst System Tensile EX # ~ in Acrylate Strength Modulus Epon 828 (80%) (20%) (MPa) (MPa) C32COM:CHDM:K~l HDDA 13.3 297.8 35COM:tBOX:CHDM:KB-l HDDA 20.7 381.6 C33COM:CHDM:KB 1 THFA 0.2 0.5 36COM:tBOX:CHDM:KB 1 THFA 8.5 162.4 C34COM:CHDM:KB-l BDDA 11.7 358.2 , 37COM:tBOX:CHDM:KB 1 BDDA 26.4 543.9 C35COM:CHDM~ l TEGDA 0.7 1.0 38COM:tBOX:CHDM:KB 1 TEGDA 6. 8 83.1 EXAMPLES 39-40 AND COMPARA~VE EXAMPLES C3~C37 A Semi-Structural, Thermosettable PSA
25This example illustrated the effectiveness of the COM/tBOX
photocatalyst system in making a pressure senstive adhesive that can be heat cured to higher bond strengths.
A coatable acrylate symp was made which contained 60 parts by weight of BA and 40 parts by weight of THFA. 0.04 part by weight of KB-1 30 photoinitiator was added to the acrylate mixture, the mixture was de-aerated with bubbling nitrogen, and the acrylate monomers wer~ taken to approximately 10% polymerization conversion by irradiation with BL-350 low intensity UV lamps. 60 parts by weight of this syrup was admixed with 40 parts by weight of the epoxy mixture that consisted of 80 parts by weight of ~0 93/1~125 PCl~-S92/1 1031 ?~ 40-Epon 828 and 20 parts by weight of Epon 1001F. 0.6 part of KB-l and 0.4 part by weight of Cp(Xyl)Pe~SbF6-, 0.4 part by weight of tBOX and 4 parts by weight of melted CHDM were added to the syrup/epoxy solution. This solution was stored in the dark until used. Prior to coating, it was de-aerated S in a vacuum chamber, then knife coated at 30 mils thickness between transparent release liners and imdiated with BL-350 low intensity UV lights at a light dosage of 1960 ml cm-2. This film was a dear, rubbery, self-supporting pressure sensitive adhesive.
Samples of these adhesives were u~ed to bond 10 cm x 1.2 cm steel 10 panel which had been zinc phosphated, primed and electro coated with General Motors EDII paint ~ypc APR16235, from Advance Coating Technologies, Inc., Hillsdale, Ml). Prior to bonding, the panels were wip~d clean with isopropanol. An overlap joint approximately 1.2 cm in length was formcd and thc bonded strips werc placed in an air circulating oven at 100C
15 for 30 minutes. Thc overlap shear bond s~ength was measured by pulling ~e bonds using an Instron Tensile Tester, model ~42~. The jaw separation rate was 5 cm min~l.
Table 1 1 Overlap Shear EX # CatalystBond Strength Bond Failure System (psi) Mode .
C36 COM 510 Adhesive C37 COM:CHDM 536 Adhesive 39 COM:tBOX 2037 Paint Failure COM:tBOX:CHDM 2169 Paint Failure Adhesive bond failure means that the bond failed at the paint-adhesive interface Paint failure means that the adhesive pulled the paint off the steel 30 substrate, and that bond failure o cured at the zinc phosphate-steel interface.

~O 93/1~12~ 2 1 2 ~ 7 ~ 1 PC~ S~2J1 1031 A One-Part EPOXY Structural Adhesive This example illustrates the use of the COM/tBOX photocatalyst system in a one-part photo-activated epoxy structural adhesive. 47.4 parts by 5 weight of Epon 828, 7.1 parts by weight of BTA IIIF and 4.7 parts by weight of WC-68 were admixed and agitated under moderate shear at 125C for one hour. Mixing was completed when the absence of gel particles was observed.
This solution was cooled to 100C and 1.0 part by weight of the catalyst, Cp(Xyl)Fe~Sb~:6 and 0.1 part by weight of bBOX, were added with 10 continuous mixing for 30 minutes or until completely dissolved. After cooling to room temperature, 8.82 parts by weight of 1,4-butane diol was added and uniformly mixed. To this mixture was added, 20.44 parts by weight of GP71 amorphous silica, 4.09 parts by weight of B37/2000 glass bubbles and 1.64 pans by weight~of TS720 fumed silica. This adhesive was knife coated at 20 15 mil thickness onto a polyester film. The coated polyester film was placed under a fluorescent lamp of the "Super Diazo Blue" type (available from Sterling Electric, Plymouth, MN). The distance between the lamp and the coating was S cm and exposure time was 3 minutes. After exposure the adhesive was removed from the polyester film. Bonds were made using 1.6 20 mm cold-rolled steel as specified in ASTM Standard A619 and converted to 2.5 cm x 10 cm st~ips from larger sheet stock. P~ior to applying the adhesive, the steel was degreased in acetone and then an automotive draw oil ARMA~ 524 (Mobil Oil Co~poration) was brushed onto the surface. After 10 minutes, excess oil was removed by wiping twice with clean cheesecloth.
25 Stainless steel spacer wire, 0.15 mm in diameter, was used to control bondline thickness. Adhesive was applied over both coupons, then 1.5 cm lengths of spacer wire were uniformly centered 0.75 cm apart across the width of one coupon. The coupons were brought together and clamped along each overlapped side with paper binder clips. The clips remained in place until the 30 adhesive was fully cured in a forced air oven at 170C for 30 minutes. Bonds were allowed to equilibrate at room temperature for a minimum of two hours prior to determining shear strength. Shear strength was determined using ~0 93/ 1 :~ 25 PCr/ ~ 2/ 1 1 ()31 . A,

7,~ 2.6~ 42 -ASTM Test Method Dl002-72 (1983) on an Instron tensile testing machine (Model # 4240) at a crosshead speed of 5 cm per minute. Four bonds were made and tested. The average bond strength of this adhesive was 2165 psi and the failure mode was cohesive.

An Epoxy-Acrylate Coating on Aluminum An epoxy-acrylate solution for aluminum coating was prepared in the following manner: 70 parts by weight of Epon 828 epoxy was mixed with 18 10 parts by weight of HDDA and 12 parts by weight of THFA. To this mixture was added 0.5 part by weight of COM, KB-l and tBOX. A comparadve solution was prepa~ed in a similar manner, except tBOX was not added.
These solutions were allowed to stand at room temperature with occasional shaking until al~ components were miscible. The solutions were knife-coated 15 at a thickness of 1.5 mils on aluminum panels that had been wiped twice with MEK. ~hree coatings of each solution were made, The coatings were UV
cured using zn RPC processor (model # QC1202 ANIR), 2 lamps on the normal setting, 2 passes, 50 feet per minute, in aiir. Aftei W processing, the coatiDgs were heat cured in an oven with a tempe~ature set at 100C for 30 20 minutes. Pencil hardness was measur~d using ASTM Test Method D-3363-74 (1989). Cross Hatch Adhesion was measured using ASTM Test Method D-3359-90. Gloss measurements were made using a Miero Tri Gloss glossometer (available ~rom BYK Gardner, Inc. Silver Springs, MD). Higher values indic~te supenor perfo~nance.
Table 12 Sample Pencil Cr~ss Hatch 20 Degree Hardness Adhesion Gloss with tBOX 4H 4.7 104.2 no tBOX 3H 3.3 100.2 ~0 93/1~1~s 2 1 2 ~ 7 ~ :~ PCl /~Sg2/11031 . ~ :

This example illustrated the effect of combining the cationic organometallic catalyst, tBOX and a peroxide, Trigonox 29 ~Trig29), on epoxy film properties. 0.l25 part each of COM and/or tBOX were dissolved 5 in 25 parts Epon 828, then 0.125 part of Trigonox 29 was added. The samples were irradiated with a BL-350 for five minutes, then cured for 30 minutes at l00C. The results are summarized the Table l3.

This example illustrated the effect of combining the cationic organometallic catalyst, tBOX and a peroxide, Trigonox 29, on epoxy-acrylate film properties. 20 parts of Epon 828 was mixed with 5 parts of T~IFA.
0. l25 part each of the catalysts were added and shaken occasionally until in solution. The samples were irradiated with a B~350 UV light for five 15 minutes, then cured for 72 hours at 100C. The results are summanzed in Table 13 Table 13 Tensile Strength Modulus EX ~Catalyst System (MPa) (MPa) C38 COM:Trig29 25.0 532.8 43COM:tBOX:Trig29 43.2 810.8 C39 COM:Trig29 43.7 686.1 44COM:tBOX:Tng29 51.5 720.8 2S EXAMPL~ 45 An epoxy-acrylate solution was prepared in the following manner: 8 parts of THFA was mixed with 2.0 parts of IBA. To this solution was added 10.0 parts of molten DEN 439. The temperature of the solution was approximately 80C. The solution was then placed on a shaker tabel 30 oYernight or until miscible. To the miscible solution was added 0.05 part each of COM, tBOX, and KB-l. 0.21 part of CHDM was then added, and the mixture was stirred on a magnetic stirrer in the dark. This solution was ~ 093/15125 Pcr/-S92/11031 Gl5~

knife-coated between two polypropylene films at a nominal l mil thickness.
The film was photolyzed between two 8 Watt 360 nm ultraviolet lights for 8 minutes. The resultant film was tacky and had good adhesive properties.
The l mm thick soda-line glass test substrate had indium-tin oxide S (ITO) circuit traces having a sheet resistance of 20 ohm/cm2 and a thickness of about lO00 Angstroms. The circuit traces are configured to permit 4 probe resistance measurement of individual pad pairs as well as the total perimeter or daisy chain value. The semiconductor test chips are 6.73 mm2 by 0.50 mm thick. They have a pad count ~f 120 and a pitch of 200 micrometers; each 10 pad is lO0 micrometers2. All pads are joined in pairs to permit daisy chain measurements. Thc aluminum straps that connect the pad pairs have rcsistances of approximately 500 milli-ohm. Resistance measurements are of pad pairs including the aluminum strap. The sample test fixture consisted of a ~bed of nails~ fixture with pressure engaged "pogo~ probes, where the probes 15 are staggered to allow each circuit trace to be contacted and measured in pairs sequentially around the substrate.
A square of ~e adhesive was pressed onto the surface of a glass having ITO circuit traces. A semiconductor chip was brought into eontact with the adhesive and a pressure of lO0 psi was applied. At that point, the 20 temperature was raised rapidly until the temperature of the heater reached 160C, then held there for about 20 seconds. The heater was then turned off and the bond was co~led under pressure until the heater temperature read approximately 60C. The substrate was then removed from the chip bonder and the number of open contacts and the resistance per side was measured.
25 Resistance of the circuit traces are summarized in Table 14.

WO 93/l~t2~ PCI/~S92/1 1031 212S7~1 An epoxy-acrylate solution was prepared according to Example 45 except DEN 439 was replaced with 5.0 parts of Quatrex2 and 5.0 parts of Quatrexl. CHDM was added in the amount of 0.97 part. Resistance of the 5 circuit traces are summarized in Table 14.

An epoxy-acrylate solution was prepared according to Example 45 except 0.2 part of coupling agent 3GPMS (available from Petrarch Chemical 10 Co.) was added. Resistance of the circuit traces are summarized in Table 14.

An epoxy-acrylate solution was prepared according to Example 45 except DEN 439 was replaced with 5.0 parts of Quatrex2 and 5.0 parts of 15 Quatrexl. CHDM was added in the amount of 0.97 part. THFA was added in the amount of 10.0 parts. Resistance of the circuit traces are summarized in Table 14.

~o 93/1~125 Pcr/~S92/1 103 . ,~

Table 14 Average Resistance No. of Open Example (ohms) Contacts Per Side*
. .
S side 1: 4.43 2 side 2: 14.84 2 side 3: 15.71 3 side 4: 6.36 side 1: 5.81 3 46 side 2: 27.89 11 side 3: 8.76 2 side 4: 0.89 7 . .
side 1: 10.20 2 47 side 2: 6.48 side 3: 2.08 2 side 4: 7.41 .
side 1: 7.01 5 48 side 2: 6.05 6 side3: 12.71 - 6 . __ side 4: 7.83 * total contacts per side is 16. L~w resistance values and low number 15 of open contacts indicate good performance.

Various modifications and alterations vf this invention will become apparent to those skilled in the art without departing ~rom the scope and spint of this invention, and it should be understood that this invention is not to be ~0 unduly limited to the illustrative embodiments set forth hereinabove.

Claims

CLAIMS:

1. A cationically polymerizable composition comprising:
(1) at least one cationically polymerizable monomer;
(2) a catalyst system comprising:
(a) at least one photoactive organometallic complex salt,<->
(b) a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, and (c) optionally, peroxide;
(3) optionally, a buffer compound; and (4) optionally, a mono- or polyfunctional alcohol.

2. The cationically polymerizable composition according to claim 1, further comprising:
(1) 1-99 wt% of at least one cationically polymerizable monomer;
(2) 0.01-20 wt% of a catalyst system comprising:
(a) 0.01-19.99 wt% of at least one photoactive organometallic complex salt, (b) 0.01-19.99 wt % of a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, and (c) 0 to 20 wt% of a peroxide;
(3) 0 to 20 wt% of a buffer compound; and (4) 0 to 50 wt% of a mono- or polyfunctional alcohol.

3. The cationically polymerizable composition according to claim 2, further comprising 0 to 98 wt% of adjuvants or thermoplastic polymers.

4. The cationically polymerizable compound according to claim 2, wherein the cationically polymerizable monomer is selected from the group consisting of epoxies, cyclic ethers, vinyl ethers, siloxanes, N-vinyl compounds, alpha-olefins, lactams, and lactones.

5. The cationically polymerizable compound according to claim 4, wherein the organometallic complex salt is selected from the group consisting of (eta6-xylenes(mixed isomers))(eta5-cyclopentadienyl) iron (1+) hexafluoroantimonate, (eta6-xylenes(mixed isomers))(eta5-cyclopentadienyl) iron (1+) hexafluorophosphate, (eta6-m-xylene)(eta5-cyclopentadienyl)iron(1+) tetrafluoroborate, (eta6-o-xylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-p-xylenes)(eta5-cyclopentadienyl)iron(1+) triflate, (eta6-toluene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-cumeme)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-p-xylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-m-xylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate (eta6-hexamethylbenzene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-naphthalene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-pyrene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-chrysene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-mesitylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroamtimonate, (eta6-cumeme)(eta5-cyclopentadienyl)iron(1+) hexafluorophosphate, (eta6-mesitylene)(eta5-cyclopentadienyl)iron(1+) pentafluorohydroxyantimonate, and (eta6-toluene)(eta5-cyclopentadienyl)iron(1+) hexafluoroarsenate.

6. The cationically polymerizable compound according to claim 5, wherein the thermally decomposable ester reaction product of a tertiary alcohol and an acid is selected from the group consisting of oxalic, phosphorous, and phosphoric acid.

7. The cationically polymerizable compound according to claim 6 further comprising 0-20 wt% of peroxide.

8. The cationically polymerizable compound according to claim 7 further comprising 0-50 wt% of a mono- or polyfunctional alcohol.

9. A polymerizable epoxy-acrylate composition comprising:
(1) at least one free radically polymerizable monomer;
(2) at least one cationically polymerizable monomer;
(3) a catalyst system comprising:
(a) at least one photoactive organometallic complex salt,<->
(b) a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, (c) optionally, peroxide, and (d) optionally, at least one free radical initiator;
(4) optionally, a buffer compound; and (5) optionally, a mono- or polyfunctional alcohol.

10. The polymerizable epoxy-acrylate composition according to claim 9, further comprising:
(1) 1-99 wt% of at least one free radically polymerizable monomer;
(2) 1-99 wt% of at least one free cationically polymerizable monomer;
(3) 0.01-20 wt% of a catalyst system comprising:
(a) 0.01-19.99 wt% of at least one photoactive organometallic complex salt, (b) 0.01-19.99 wt% of a thermally decomposable ester reaction product of a tertiary alkyl alcohol and an acid that forms a chelation complex with the metal ion of the organometallic complex salt, (c) 0 to 20 wt% of a peroxide, and (d) 0 to 20 wt% of at least one free radical initiator;
(4) 0 to 20 wt% of a buffer compound, and (5) 0 to 50 wt% of a mono- or polyfunctional alcohol.

11. The polymerizable epoxy-acrylate compound according to claim 10, further comprising 0 to 97 wt% of adjuvants or thermoplastic polymers.

12. The polymerizable epoxy-acrylate compound according to claim 10, wherein the cationically polymerizable monomer is selected from the group consisting of epoxies, cyclic ethers, vinyl ethers, siloxanes, N-vinyl compounds, alpha-olefins, lactams, and lactones.

13. The polymerizable epoxy-acrylate compound according to claim 12, wherein the free radically polymerizable monomer is selected from the group consisting of (meth)acrylates, (meth)acrylamide, and vinyl compounds.

14. The polymerizable epoxy-acrylate compound according to claim 13, wherein the organometallic complex salt is selected from the group consisting of (eta6-xylenes(mixed isomers))(eta5-cyclopentadienyl) iron (1+) hexafluoroantimonate, (eta6-xylenes(mixed isomers))(eta5-cyclopentadienyl) iron (1+) hexafluorophosphate, (eta6-m-xylene)(eta5-cyclopentadienyl)iron(1+) tetrafluoroborate, (eta6-o-xylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-p-xylenes)(eta5-cyclopentadienyl)iron(1+) triflate, (eta6-toluene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-cumeme)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-p-xylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-m-xylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate (eta6-hexamethylbenzene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-naphthalene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-pyrene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-chrysene)(eta5-cyclopentadienyl)iron(1+) hexafluoroantimonate, (eta6-mesitylene)(eta5-cyclopentadienyl)iron(1+) hexafluoroamtimonate, (eta6-cumeme)(eta5-cyclopentadienyl)iron(1+) hexafluorophosphate, (eta6-mesitylene)(eta5-cyclopentadienyl)iron(1+) pentafluorohydroxyantimonate, and (eta6-toluene)(eta5-cyclopentadienyl)iron(1+) hexafluoroarsenate.

15. The polymerizable epoxy-acrylate compound according to claim 14, wherein the thermally decomposable ester reaction product of a tertiary alcohol and an acid is selected from the group consisting of oxalic, phosphorous, and phosphoric acid.

16. The polymerizable viscoelastic epoxy-acrylate compound according to claim 14, wherein the free radical initiator is selected from the group consisting of acetophenones, ketals, aryl gloxalates, acylphosphine oxides, and aromatic halonium salts.

17. The polymerizable viscoelastic epoxy-acrylate compound according to claim 16, further comprising 0-20 wt% of peroxide.

18. The polymerizable viscoelastic epoxy-acrylate compound according to claim 17, further comprising 0-50 wt% of a mono- or polyfunctional alcohol.

19. An epoxy coating comprising (a) a substrate, and (b) a polymerized product according to claim 1.

20. The epoxy coating according to claim 19 wherein the polymerized product comprises (a) a cationically polymerizable monomer is selected from the group consisting of digylcidyl ether of bisphenol A (epoxy eq. wt of 185-192 g/eq.), 3,4,epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate,, (b) Cp(Xyl)Fe+SbF6-, (c) oxalate ester, (d) cyclohexanedimethanol and (e) a peroxide.

21. An epoxy free standing film comprising a polymerized product according to claim 1.

22. The epoxy free standing film according to claim 21 wherein the polymerized product comprises (a) a cationically polymerizable monomer selected from the group consisting of digylcidyl ether of bisphenol A (epoxy eq. wt of 185-192 g/eq.), 3,4,epoxycylcohexylmethyl-3,4-epoxycyclohexanecarboxylate, and bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate,, (b) Cp(Xyl)Fe+SbF6-, (c) oxalate ester, (d) cyclohexanedimethanol and (e) a peroxide.

23. An epoxy structural adhesive comprising a polymerized product according to claim 1.

24. The epoxy structural adhesive according to claim 23 wherein the polymerized product comprises (a) a cationically polymerizable monomer selected from the group consisting of digylcidyl ether of bisphenol A (epoxy eq. wt of 185-192 g/eq.), 3,4,epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate,, (b) Cp(Xyl)Fe+SbF6-, (d) di-benzyl-t-butyl oxalate, (d) 1,4-butanedioland (e) a film toughener.

25. An epoxy-acrylate coating comprising (a) a substrate, and (b) a polymerized product according to claim 9.

26. The epoxy-acrylate coating according to claim 25 wherein the polymerized product comprisings (a) a cationically polymerizable monomer selected from the group consisting of digylcidyl ether of bisphenol A (epoxy eq. wt of 185-192 g/eq.), 3,4,epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate, (b) an acrylate monomer selected from the group consisting of 1,6-hexanediol diacrylate, tetrahydrofurfuryl acrylate, 1,4-butanediol diacrylate, and tetraethylene glycol diacrylate, (c) Cp(Xyl)Fe+SbF6-, (d) an oxalate ester, (e) cyclohexanedimethanol, (f) benzil dimethoxy ketal, and (g) a peroxide.

27. An epoxy-acrylate free standing film comprising a polymerized product according to claim 9.

28. The epoxy-acrylate coating according to claim 25 wherein the polymerized product comprisings (a) a cationically polymerizable monomer selected from the group consisting of digylcidyl ether of bisphenol A (epoxy eq. wt of 185-192 g/eq.), 3,4,epoxycyclohexylmethyl-3,4-epoxycyclohexanecarboxylate, and bis(3,4-epoxy-6-methylcyclohexylmethyl) adipate, (b) an acrylate monomer selected from the group consisting of 1,6-hexanediol diacrylate, tetrahydrofurfuryl acrylate, 1,4-butanediol diacrylate, and tetraethylene glycol diacrylate, (c) Cp(Xyl)Fe+SbF6-, (d) an oxalate ester, (e) cyclohexanedimethanol, (f) benzil dimethoxy ketal, and (g) a peroxide.

29. An epoxy-acrylate semi-structural, thermosettable pressure sensitive adhesive comprising a polymerized product according to claim 9.

30. The epoxy-acrylate semi-structural, thermosettable pressure sensitive adhesive according to claim 29 wherein the polymerized product comprises (a) a cationically polymerizable monomer selected from the group consisting of digylcidyl ether of bisphenol A (epoxy eq. wt of 185-192 g/eq.), and digylcidyl ether of bisphenol A (epoxy eq. wt. of 525-550 g/eq.), (b) an acrylate monomer selected from the group consisting of butyl acrylate, 1,6-hexanediol diacrylate, tetrahydrofurfuryl acrylate, isooctyl acrylate, and tetraethylene glycol diacrylate, (c) Cp(Cum)Fe+PF6- or Cp(Xyl)Fe+SbF6-, (d) an oxalate ester, (e) cyclohexanedimethanol, (f) benzil dimethoxy ketal, and (g) a peroxide.

31. An epoxy-acrylate conductive adhesive comprising (a) conductive particles and (b) a polymerized product according to claim 9.

32. The epoxy-acrylate conductive adhesive according to claim 31 wherein the polymerized product comprises (a) a cationically polymerizable monomer selected from the group consisting of high purity liquid bisphenol A
epoxy resin (epoxy eq. wt of 185-190 g/eq.), high purity liquid bisphenol A
epoxy resin (epoxy eq. wt. of 450-575 g/eq.), and epoxy novolac resin (epoxy eq. wt. of 191-210 g/eq.), (b) an acrylate monomer selected from the group consisting of butyl acrylate, 1,6-hexanediol diacrylate, tetrahydrofurfuryl acrylate, isooctyl acrylate, and tetraethylene glycol diacrylate, (c) Cp(Cum)Fe+PF6- or Cp(Xyl)Fe+SbF6-, (d) an oxalate ester, (e) cyclohexanedimethanol, (f) benzil dimethoxy ketal, (g) a peroxide and (h) conductive particles.

[(L1)(L2)MP]+q Yn wherein MP represents a metal selected from the group consisting of: Cr, Mo, W, Mn Re, Fe, and Co;
L1 represents 1 or 2 ligands contributing pi-electrons that can be the same or different ligand selected from the group of: substituted and unsubstituted eta3-allyl, eta5-cyclopentadienyl, and eta7-cycloheptatrienyl, and eta6-aromatic compounds selected from eta6-benzene and substituted eta6-benzene compounds and compounds having 2 to 4 fused rings, each capable of contributing 3 to 8 pi-electrons to the valence shell of MP;
L2 represents none or 1 to 3 ligands contributing an even number of sigma-electrons that can be the same or different ligand selected from the group of: carbon monoxide, nitrosonium, triphenyl phosphine, triphenyl stibine and derivatives of phosphorus, arsenic and antimony, with the proviso that the total electronic charge contributed to MP results in a net residual positive charge of q to the complex;
q is an integer having a value of 1 or 2, the residual charge of the complex cation;
Y is a halogen-containing complex anion selected from BF4-, AsF6-, PF6-, SbF5OH-, SbF6-, and CF3SO3-; and n is an integer having a value of 1 or 2, the number of complex anions required to neutralize the charge q on the complex cation; of the general formula