CA1159193A - Polymer-polyols and polyurethanes based thereon - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Fluid, stable polymer-polyols are provided which consist of an organic polyol medium and an inter-polymer of a minor amount of polymerized ethylenically unsaturated dicarboxylic acid anhydride, such as maleic acid anhydride, and a major amount of at least one different polymerized ethylenically unsaturated monomer, the interpolymer being in the form of particles that are stably dispersed in the polyol.
Polyurethane foams produced from these polymer/polyols display improved load bearing and compression set when compared with polymer/polyols produced in a similar manner without the ethylenically unsaturated dicarboxylic acid anhydride; elastomers so produced have improved tensile modulus and tear properties.

RELATED APPLICATIONS
Priest, U. S. Patent No. 4,208,314.
Simroth, U. S. Patent No. 4,104,236.
Van Cleve et al. U. S. Patent No. 4,172,825.

Description

~ 159193 1~,895 BACXGR~UND OF ~HE INVENTION

Polymer/polyol compositi~ns suitable for use in producing polyurethane f~ams, elast~mers and the like are known materials. The basic patents in this field are U.S.
3,304,273, 3,383,351, Re. 28,715 and Re. 29,118 to ~tamberger.
Such compositions can be produced by polymerizing one or more ole~inically unsaturated monomers dissolved or dispersed in a poly~l in the presence of a free radical catalyst. Many Exam-ples in the Stamberger patents utilize various carboxylic acids in the monomer mixtures; and, more particularly, itaconic acid is used by itself and as a co-monomer present as a minor constitutent based on the total weight of the monomer mixture. These polymer/polyol compositions have the valuable property of imparting to, for example, polyurethane foams and elastomers produced therefrom, higher load-bearing properties than are provided by unmodified polyols.
In addition, U.S. 3,523,093 to Stamberger discloses a meth~d for preparing polyurethanes by reacting a polyiso-cyanate with a mixture of a polyol solvent medium and a pre-formed normally solid film-forming polymeric m~terial obtained by polymerization of ethylenically unsaturated monomers. The film-forming polymer may be prepared by various techniques, including polymerizing the monomers in the presence of react-ive radical-containing compounds ~uch as alcohols and mer-c~ptan~.
The polymer/polyol compositions that found ~nitlal commercial acceptance were primarily composition6 produced from polyols and acrylonitrile. Such compositions were some-what higher in viscosity than desired in ~ome applications.
Further, ~uch compositions were at least primarily used

-2-. ~159193 10,~95 commercially in producing foams under conditions ~uch that the heat generated during foaminq is readily dissipated le.q. ~ the foams ale a relatively thin cross-~ection) or under conditions such that relatively little heat i~ gener-ated during foaming. When polyurethane foams were produced under condit~ons such t~at the heat generated during foaming was not readily dissipated, severe foam scorchins usually resulted. Later polymer/polyol compositions produced from acrylonitrile-methymethacrylate mixtures were commercialized and were converti~le to p~lyurethane foams ~aving reduced scorch.
More recently, polymer~polyol compositions produced from polyols and acrylonitrile or acrylonitrile-styrene mux-tures have been used commercially. The Pr~est U. S. Patent Nb. 4,208,314 identified herein provides an improved process for forming such polymer/polyols which includes, in general, maintaining a low monomer concentration throughout the reac-tion mixture during the process. The novel polymer/polyols produced have low viscosities, also the Priest polymer/poly-ols can be converted to low density, water-blown polyurethane foams having reduced scorch, especially at relatively low acrylonitrile to styrene ratio~. However, the ~tability of the polymer/polyols decreases with increasing styrene-t~-acrylonitrile ratios. Further, the discoloration (scorch) of the resulting foams still presents ~ome problems, particu-larly when the polymer composition eontains a relatively high acrylonitrile-to-styrene ratio.
Still further, the Simroth U.S. Patent No. 4,104,236 which has been identified diEcloses addition~l ~nd ~ubstan-tial improvements in forming potymer~polyols. ~h~s allow~the optimization of the polymer content ana the usable mono-~3 ....
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, .

i15g~93 mer ratios for a given polyol in providing satisfactory stable polymer/polyols.
The previously identified Van Cleve et al. U.S.
Patent No. 4,172,825 discloses further improvements in the formation of polymer/polyols. As discussed therein, polymer/polyol compositions exhibiting outstanding properties can be made by utilizing, in the formation of the polymer/polyols, a specific type of peroxide catalyst, namely t-alkyl per-oxyester catalysts. By the utilization of this specific type of catalyst, polymer/polyols can be produced on a commercial basis with outstanding properties such as filterability in processing, yet which allow either the polymer or the styrene content to be increased. Also, polymer/polyols can be produced on a commercial scale with polyols having a molecular weight lower than have been used prior to this invention.
Despite these improvements, there is still room for further refinement. Commercial production thus requires that the resulting polymer/polyols have relatively low vis-cosities so that processing in the production equipment can be economically carried out. Further, the stability re-sulting must be sufficient to allow operation without plugging or fouIing of the reactors as well as allowing for relatively long term storage.
The polymer/polyols must also be capable of being pro-cessed in the sophisticated foam equipment presently being used. Typically, the prime requirement is that the polymer/
polyols possess sufficiently small particles so that filters, pumps and the like do not become plugged or fouled in relatively short periods of time.
While somewhat simplified, the commercial process-ability of a particular polymer/polyol comes down to its - ~ 1591'~3 ( 10,89s viscosity ~nd stability against phase ~eparation. Lower viscosities are of substa~ti~l practical and economic signi-ficance due to the ease of pumping and meterins as well as ease of mixing during the formatioll of polyuretha~es. Sta-bility is of prime consideration in insuring that the poly-mer/polyols can be processed iD commercial production equip-ment without the necessity of additional mixing to insure homogeneity.
Acc~rdingly, any improvements which impart more lD desirable properties to the resulting polyurethanes without increasing viscosity or stability problems would ~e favor-ably received. Unfortunately, it has been the experience that increased load-bearing in foams and modulus in elast-omers are usually associated with increased viscosity in the polymPr/polyol.
It has been theorized that the stability of poly-mer/polyols requires the presence of a minor amount of a graft copolymer formed from the polymer and polyol. ~nd, a number of literature references have ob~erved large dif-ferences in grafting efficiency between the use of peroxidessuch as benzoyl peroxide and azobis-isobutyronitrile in certain monomer-polymer systems while others have noted no marked differences.
In the Journal of Cellular Plastics, March, 1966, entitled ~Polymer/Polyols; A New Class of Polyurethane Intermediates~ by Ruryla et al., there is reported a series of precipitation experLments run to determine any ~arked differences in the polymer~polyols produced b~ either benzoyl peroxide ~r azobis-i60~utyronitrile when used as the initia-tors in the in itu polymerization of acrylonitrile in a poly (oxypropylene)triol having a theoretical numbær average ~O,B~5 molecular weight of about 3000. ~he data indicated no significant differences between the polymers is~lated, and no marked ~initiator effect" was o~served.
With regard to addition copolymer stabilizers, efforts in the polymer/polyol field have been concer~ed with the incorporation of additional amounts of unsaturation to that inherently present in the polyoxyalkylene polyols typi-cally used in formin~ polymer~polyols. U.S. patents 3,625,639 and 3,823,201 and U.S. 3,850,861 all utilize this approach.
The theory is presumably that increased amounts of the sta-bilizing species will be formed by addition polymerization upon polymerizing whatever ethylenically unsaturated monomers are employed in such polyols.
U.S. 3,850,861 thus discloses the in situ polymer-ization of ethylenically unsaturated monomers in an unsatur-ated polyol. Suita~le unsaturated polyols are prepared by using an ethylenically unsaturated mono- or polyhydric ini-tiator to form a po'yalkylene oxide. The examples set forth include dibasic acids or their derivatives, such as maleic acid. The polyol polymerization medium thus contains one mole of unsaturation per mole of polyol.
V.S. 3,652,639 likewise discloses the in 6itu polymerization of ethylenically unsaturated monomers in an ethylenically unsaturated polyol medium. The unsaturated polyols of this patent are produced in a manner ~imilar to those of V.S. 3,823,201, as will be discussed hereinafter, except that the level of unsaturation is higher, being on the order ~f 1 to 3 moles of unsaturation per mole of polyol.

~ .S. 3,823,201 discloses a method of preparing a polymer/polyol ~y the $n ~itu polymerization of et~ylenically unsaturated mo~omers ~n a poly~l having from 0.1 to 0.7 mole ~1591'~3 10,895 of unsaturation per mole of polyol. ~nsaturation at the levels set forth in the U.S. 3,652,639 patent were lndicated as imparting unnecessarily high viscosities to the resulting polymer/polyols. The unsaturation level that is added can be introduced into the polyol by reacting it with an ethylen-ically unsaturated compoun~ that is capable of ~dding to the polyol by reaction with the hydroxyl group, such as maleic anhydride. The polymer/polyols disclosed in V.S. 3,823,201 are asserted t~ be highly sta~le due to the presence of the stabilizing species which is formed via the grafting of vinyl polymer chain segments to the unsaturated polyol molecules.
Certain improvements in polyurethanes using such polymer/
polyols are likewise asserted. More particularly, it is stated that such polymer/polyols are surprisingly superior t~ those prepared from polyols having high unsaturation in regard to their low viscosities. It is further alleged that polyurethane foams prepared from these graft copolymers exhibit superior load-bearing properties.
A prime difficulty with incorporating additional unsaturati~n into the polyols such as by the techniques set forth in U.S. 3,652,639 is that an additional step is required and/or processing is made more difficult. The use of maleic anhydride to introduce the additional unsaturation requires an additional step. Moreover, improvements in properties of polyurethanes do not necessarily result; and undesirable increases in viscosity of the polymer/polyol can result.

SUMMARY OF THE INVENTI~N
The present inven~ion thus provides novel, improved, highly stable polymer/polyols and methods for their prepara-tion as well as polyurethane products made therefrom. In ~ 159193 10,895 general, this invention is b~sed on the disco~ery that when a min~r amount of ~n ethylenically unsaturated dicarboxylic acid anhydride is inc~rporated with other ethylenically un-saturated monom~rs to form a monomer mixture which is poly-merized ln situ in a polyel medium, the resulting polymer/
polyols will impart improved properties to polyurethane products made therefrom. More specifically, polyurethane foams so produced have compression set and load-bearing properties superior to those of foams based on similar polymerfpolyols produced without the use of the ethylenically unsaturated dicarboxylic acid anhydride in the monomer mix-ture. Polyurethane elastomers made according to this inven-tion exhibit improved tensile modulus and tear properties.
In view of the experience of the prior art that increasing load-bearing properties are usually associated with increased viscosity in the polymer/polyol, it is surprising that the pol~mer/polyols of the present invention display viscosities on the same order as, and in some instances even lower than, the viscosities of comparable polymer/polyols not employing the ethylenically unsaturated dicarboxylic acid component of the monomer mixture. In most instances, the seed content of the polymer/polyols of this invention, measured as mg.
of 150 mesh seeds~100 g. of polymer/polyol, which is consid-ered to be one measure of ~tability, is not significantly higher than the seed content of comparable polymer/polyols not employing the ethylenically unsaturated dicarboxylic acid anhydride component.
It is believed that the novel polymer/polyols of this invention comprise a disper~ion of ~n interpolymer of an ethylenically unsaturated dicarboxylic acid anhydride and at least one other ethylenically unsatur~ted monomer in an organic pOlyDl medium in which there is ~lso present 60me li 1 5~ 193 10,B95 graft cQpolymer pr~duced when a p~rti~n of the ethyle~ically unsaturated dicarboxylic acid anhydride units, which have p~lymerized into the p~lymer backbone, undergo a reaction with the hydroxyl groups of the polyol. It is further theorized that the graft copolymer species acts as a stabil-izer for the polymer dispersion as well as providi~g a means by which the polymer particles form a bond to the polyure- ., thane formed when the polymer/polyol is reacted with a poly-isocyanate.

DETAILED DESCRIPTION OF THE INVENTION
The novel improved polymer/polyols of this inven-tion comprise fluid, stable polymer/polyols of: (1) from about 60 to about 90 weight percent of an organic polyol medium consisting essentially of at least one normally liquid poly~l and (2) from about 10 to about 40 weight percent of an interpolymer of (a) a minor amount of polymerized ethyl-enically unsaturated dicarboxylic acid anhydride and ~b) a major amount of at least one different polymerized ethylen-ically unsaturated monomer, the interpolymer being in the form of particles that are stably dispersed in the polyol and the weight percents being based on the total weight of the polymer ~nd polyol.
The organic polyols useful in this invention are well known compounds. Functionally useful polyols should be liquid ~t room temperature and act as dispersing ~edia for the polymers formed by the in situ polymerization of the mixture of ethylenically unsaturated monomers therein.
The preferred organic polyols are the propylene oxide adducts of mono-, di-, tri-; or polyhydroxy alkanes.

~ 159193 10,895 Such p~lyols include poly~oxypr~p~lene) polyols which may also have oxyethylene prese~t; however, desirably, the oxy-ethylene content shoul~ comprise less than about 50 percent of the total ~nd, preferably, less than about 20 percent, when the polymer/polyols are to be used in forminq poly-urethane foams. The oxyethylene units can be incorp~rated in any fashion along the polymer chain. Stated another way, the oxyethylene units can either be incorporated in internal blocXs, as terminal blocks, or may be randomly distributed along the polymer chain. As is known in the art, the pre-ferred p~lyols do normally contain varyinq amounts of unsat-uration. The extent of unsaturation typically involved does not affect in any adverse way the formation of the polymer/
polyols in accordance with the present invention.
For the purposes of this invention, useful polyols should have a number average molecular weight of about 400 or greater, the number average used herein being the value derived from the hydroxyl number and the theoretical hydroxyl functionality. The true number average molecular weight may be somewhat less, dependin~ upon the extent to which the true molecular functionality is below the starting or theo-reti~al functionality.
The polyols empleyed can have hydroxyl numbers which vary over a wide range. In general, the hydroxyl numbers of the polyols employed in the invention can range from about 20 and lower, to about 280 and higher. The hydroxyl number is defined as the number of milligrams of potassium hydroxide required for the complete hydrolysis of the fully phthalylated derivative prepared from 1 gram of polyol. The hydroxyl ~umker can ~lso be defined by the e~uation:

~ 1 591 93 OH ~ 56.1 x 1000 x f m.w.
where OH = hydroxyl number of the polyol f - functionality, that is, average number of hydroxyl groups per molecule of polyol m.w. = molecular weight of the polyol.
The exact polyol employed depends upon the end use of the polyurethane product to be produced. The molec-ular weight or the hydroxyl number is selected properly to lD result in flexible or semi-flexible foams or elastomers when the polymer-polyol produced from the polyol is converted to a polyurethane. The polyols preferably possess a hydroxyl number of from about 50 to about 150 for semi-flexible foams and from about 20 to about 70 for flexible foams. Such limits are not intended to be restrictive, but are merely illustrative of the large number of possible combinations of the above p~lyol coreactants.
As alternatives to the preferred poly(oxypropylene) polyols, any other type of known polyol may also be used.
Among the polyols which can be employed are one or more polyols from the following classes of compositions, known to those skilled in the polyurethane art:
(a) Alkylene oxide adducts of non-reducing sugars and sugar derivatives;
(b) Alkylene oxide adducts of phosphorus and polyphosphorus acids;
(c) Alkylene oxide adducts of polyphenols;
(d) The polyols from natural ~ils such as castor oil, and the like;
(e) Alkyl~ne ~xide adducts ~f polyhydroxy-alkanes other than th~se already ~ S 59193 10,895 described herein;
(f) Polyester polyols;
~g) Alkyle~e oxide ~dducts of primary or secondary amines such AS ethylene diamine, diethylene triamine, etc.
Illustrative alkylene oxide adducts of pDly-hydroxyalkanes include, among others, the alkylene oxide adducts of 1, 3-dihydroxypropane, 1, 3-dihydroxybutane, 1,4-dihydroxybutane, 1,4-, l,S- and 1,6-dihydroxyhexane, 1,2-, 1,3-, 1,4-, 1,6-, and 1,8-dihydroxyoctane, 1,10-dihydroxydecane, glycerol, 1,2,4-trihydroxybutane, 1,2,6-trihydroxyhexane, 1,1,l-trimethylolethane, 1,1,l-trimethyl-olpropane, pentaerythritol, caprolactone, polycaprolactone, xylitol, arabitol, s~rbitol, mannitol, and the like.
A further class of polyols which can be employed are the al~ylene oxide adducts of the non-reducing sugars, wherein the alkylene oxides have from 2 to 4 carbon atoms.
Among the non-reducing sugars and sugar derivatives con-templated are sucrose, alkyl glycosides such as methyl glucoside, ethyl glucoside, and the like, glycol glycosides such as ethylene glycol glucoside, propylene glycol glucoside, glycerol glucoside, 1,2,6-hexanetriol glucoside, and the like, as well as the alkylene oxide adducts of the alkyl glyc~sides as set forth in U.S. 3,073,788.
A still further useful class of polyol is the polyphenols, and preferably the alkylene oxide adducts thereof wherein the alkylene oxides have from 2 to 4 carbon atoms. Among the polyphenols which ~re ccntem-plated ~re, for ~xample, bisphenol A, bisphenol F, con-densation products of phenol and formaldehyde r the novalacresins; conden~ation products of various phenolic compounds ~159193 10,895 and acrolein; the simplest members of this class being the 1,1,3-tris(hydroxyphenyl) propanes, condensatioa products of various phenolic compounds and glyoxal, glutaraldehyde, and other dialdehydes, the simplest members of this elass being the 1,1,2,2-tetrakis(hydroxyphenol)-ethanes, and the like.
The alkylene oxide adducts of phosphorus and polyphosphorus acids are another useful class of polyols.
Ethylene oxide, 1,2-ep~xypropane, the epoxybutanes, 3-chloro-1,2-epoxypropane, and the like are preferred alkylene oxides. Phosphoric acid, phosphorus acid, the polyphosphoric acids such as tripolyphosphoric acid, the polymetaphosphoric acids, and the like are desirable for use in this connection.
One can mention, as illustrative of the useful polyester polyols, those produced by polymeri~ing a lac-tone monomer in the presence of a polyhydric initiator.
Suitable lactone monomers have the formula:

R - CH (1) C = O
I n wherein n is an integer having a value from about 3 to about 6, ~t l east n + 2 R's are hydrogen and the remaining R's are each lower alkyl (1-3 carbons~. As illustrative of suitAble lactone monomers one can mention epsilon-caproiactone delta-valerolactone; ~eta-enantholactone;

~ ~591~3 10,895 the monoalkyl-delta-valerolactones; e.g., the monomethyl-, monoethyl-, monohexyl- delta-valerolactones, and the like; the dialkyl-del~a-valerolactones, e.g., the dimethyl-, diethyl-, and di-n-octyl-delta-valerolactones, ~nd the like; the monoalkyl-, dialkyl-, and trialkyl-epsilon-caprolactones, e.g. the monomethyl-, monoethyl-, monohexyl-, dimethyl-, diethyl-, di-n-propyl-, di-n-hexyl-, trimethyl-, '' triethyl-, tri-n-propyl-epsilon-caprolactones, and the like.

The suitable polyhydric initiators are well known and in-clude, for example, glycerol, trimethylolethane, trimethyl-olpropane, diethylene glycol; 1,2,4-butanetriol, 1,2,6-hexanetriol, pentaerythritol, neopentyl glycol, 1,4-but-anediol, 3'-~.ydroxy- 2',2'-dimethylpropyl 3-hydroxy-2, 2-dimethylpropionate, and the like.
The polyols described above are listed as merely illustrative of those which are useful in this invention and any known organic polyol or mixture of such polyols is suitable.

The mixture of ethylenically unsaturated mono-mers which is polymeri~ed in situ in the organic polyol medium has two components. The first component is the ethylenically unsaturated dicarboxylic acid anhydride, maleic anhydride being preferred. Other illustrative examples of useful materials are the anhydrides of itaconic, propenyl succinic, citraconic, mesaconic, cyclohexene dicarboxylic, and endomethylene cyclohexene dicarboxylic acids, and the like.
Conceptually, compounds other than anhydrides may be employed. To be useful, the compound must contain unsatur-ation so as to be capable of interpolymerizing with the ~ ~5919 3 10, ~gs ethylenically unsaturated monomer or monomers used. Still further, the compound must contain a functional group that is reactive wi~h the hydroxyl groups of the polyol employed.
The component should be present, in theory, in a minor amount ~ince the basis for inclusion is to provide property improvements in polymer/polyols`formed from other .-types of ethylenically unsaturated monomers. As far as a minimum is concerned, a sufficient amount should be utili~ed to provide the desired product improvements. In this connec-tion, an amount as small as 0.5 percent, based on the total weight of the monomer mixture, may prove satisfactory in some applications. On the other hand, increasing amounts of the anhydride compo~ent will result in increasing acid numbers for the polymer/polyols so formed. This is undesir-able in foam applications since either reformulations (from those conventionally used) are needed to avoid foam collapse or some other modi~ication must be undertaken to reduce the acid number. Thus, acid numbers in excess of about 1.5 mg.
KOH/g. are typically considered undesirable. Further, and importantly, the amount need be no more than that required to provide the desired property improvement. For these reasons, the maximum amount desirably used will typically be no more than 10 weight percent, although some applications m~y find amounts up to 20 weight percent even more useful.
The preferred range is accordingly from about 0. 5 eo 20 weight percent, more preferably 0.5 to 10, ~nd even m~re prefera~ly, 2.5 to 6.

The other comp~nent in the ethylenically unsatur-ated monomer mixture is considerably broader in it6 scope 10,895 ~ 1S91!33 than the anhydride c~mponent. It is necessary only that the monomer have at least one polymerizable ~C ~ C< group and be compatible with the orga~ic p~lyol medium. ~t is preferred that this monon,er contain no radicals which are reactive with the organic polyol under the processing conditions of this invention, e.g., oxirane, oxe~ane, i60-cyanate, etc. These ethyle~ically unsaturated monomers can L
be employed singly or in combinations.
Acrylonitrile or mixtures thereof with a comonomer such as styrene are commonly used in preparing polymer/polyols.
What acrylonitrile/styrene ratios are used, or indeed whether other monomers are used, will be dependent upon factors such as the type of properties required as well as ease in pro-cessability in preparing the polymer/polyols.
Other suitable ethylenically unsaturated m~nomers that can be employed include butadiene, isoprene, 1,4-penta-diene, 1,6-hexadiene, 1,7-octadiene, alphamethylstyrene, methylstyrene, 2,4-dimethylstyrene, ethylstyrene, isopropyl-styrene, butylstyrene, phenylstyrene, cyclohexylstyrene, benzylstyrene, and the like, s ~ ~itu~ed styrenes such as chlorostyrene, 2,5-dichl~rostyrene, bromostyrene, fluorostyrene, trifluoromethylstyrene, iodostyrene, cyanostyrene, nitroso-styrene. N,N-dimethyl-aminostyrene, acetoxystyrene, methyl 4-vinylben~oate, phenoxystyrene, p-vinyl diphenyl sulfide, p-vinylphenyl phenyl oxide, and the like; the acrylic and cubstituted acrylic monomers such as acrylic acid, methacrylic acid, methylacrylate, 2-hydroxyethyl acrylzte, 2-hydroxyethyl methacrylate, methyl methacrylate, cyclohexyl methacrylate, ben~yl methacrylate, isopropyl methacrylate, octyl ~etha-crylate, methacrylonitrile, methyl alpha-chloracrylate, -~6-~ 193 10,895 ethyl alpha-ethoxyacrylate, methyl alpha-acetaminoacrylate, butyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, phenyl methacrylate, alpha-chloroacrylonitrile, N,~-dime-thylacrylamide, N,N-diben~ylacrylamide, N-butylacrylamide, methacrylyl formamide, and the like; t.he vinyl esters, vinyl ethers, vinyl ketones, etc. such as vinyl acetate, vinyl chloroacetate, vinyl butyrate, iso~ropenyl acet.ate, vinyl formate, vinyl acrylat.e, vinyl methacrylate, vinyl met.hoxy acetate, vinyl ben~oate, vinyl iodide, vinyl toluene, vinyl naphthalene, vinyl bromide, vinyl fluoride, vinylidene bromide, l-chloro-l-fluoroethylene, vinylidene fluoride, vinyl methyl ether, vinyl ethyl ether, vinyl propyl ethers, vinyl butyl ethers, vinyl 2-ethylhexyl ether, vinyl phenyl ether, vinyl 2-methoxyethyl ether, met.hoxybutadiene, vinyl 2-butoxyethyl ether, 3,4-dihydro-1,2-pyran, 2-but.oxy-2'-vinyloxy diethyl ether, vinyl 2-ethylmercaptoethyl ether, vinyl methyl ketone, vinyl ethyl ketone, vinyl phenyl ketone, vinyl ethyl sulfide, vinyl ethyl sulfone, N-methyl-N-vinyl acetamide, N-vinylpyrrolidone, vinyl imida~ole, divinyl sulfide, divinyl sulfoxide, divinyl sulfone, sodium vinyl sulfonate, methyl vinyl sulfonate, N-vinyl pyrrole, and the like; dimethyl fumarate, dimethyl maleate, maleic ~cid, crotonic acid, fumaric acid, itaconic acid, monomet.hyl itaconate, t-butylaminoethyl methacrylate, dimethylaminoethyl methacrylate, allyl alcohol, glycol monoesters of itaconic acid, dichlorobutadiene, ~inyl pyridine, and the like. Any of t.he known polymerira~le monomers can ~e used, and the compounds listed above ~re illustrative and not restri~tive of the monomers ~uit.~ble for use in this invention.

~ ~59193 10,895 The total weight Gf the monomer mixture used is desirably fn the range of from about 10 to about 40 weight percent, based on the total weight of the ~ixture and the polyol. The amount would be reduced to perhap~ 5 ~eight percent or ~o, but process efficiency would be gre~tly reduced.
On the other hand, amounts up to 50 weight percent might be used, if desired. T~,e weight of the monomer ~ixture c~n generally be equated to the weight of the resulting polymer since conversions often approach 100 percent. However, the weight of the monomer mixture used can certainly be increasea as needed to provide whatever polymer content i8 desired in those situations where conversions of monomer to polymer is substantially less than 100 percent.
The improved polymer/polyols are produ~ed by poly-merizing the mixture of ethylenically unsaturated ~onomers in the organic polyol medium at a temperature of from about 100C to 150C., preferably from 115C. to 125C. in the presence of a catalytically effective amount of a conventional free radical catalyst known to be suitable for the polymeri-zation of ethylenically unsaturated monomers.
The polymer/polyols of the present invention arepreferably produced by utilizing the process set forth in the copending U.S. Paten~ No. ~2~t~14 by ~riest, previously identified herein. ~n accordance with that process, a low monomer to polyol ratio is maintain~d throughcut the reaction mixture during the process. Thi~ is achieved by employing conditions that provide rapid conver~ion of mono~er to poly-mer. ~n practice, a low monomer to polyol r~tio i~ ~a~ntained, in the ca~e of ~e~ atch ~nd continuou~ operation, by control of the temperature and mixing conditions and, in the case of ~emi-batch oporation, al~o by ~lowly ~dding ~h~ monomer~ ~o . ~ ~59193 10,~95 the polyol.
The mixing conditions employed are those obtained using a back mixed reactor (e.g. -- a stirred flask or ~tir-red a~toclave). The reactors of this type keep the reaction mixture rel~tively homogeneous ~nd 50 prevent loc~lized high monomer to polyol ratios s~ch as occur in certain tubular reactors, e.g. -- in the first stages of "Marco" reactors !~
when such reactors are operated with all the monomer added to the first stage.
The utilization of the Priest process is preferred since this allows the preparation of polymer/polyols with a wide range of monomer compositions, polymer contents and polyols that could not be otherwise prepared with the neces-sary re~uisite stability. ~owever, whether the utilization of the Priest process is essential depends upon whether the process parameters are such that a satisfactory polymer/
polyol can be prepared without using this process.
In the case of continuous or semi-batch production of the polymer/polyol, the relative proportions of ~onomers in the monomer mixture feed stream ti.e., ethylenically un-saturated dicarboxylic acid anhydride and other ethylenically unsaturated monomer or monomers) can be constant throughout the reaction or may be varied during the reaction, provided only that the total amounts of the anhydride and other ethyl-enically unsaturated monomers fed to the reactor during the reaction are within the proportional range 6et forth above.
For example, the proportion of the anhydride in rel~tion to the other ethylenically unsaturated monomers in the feed ~tream may remain o~nctant at the desired overall concentration or it may te less than the de8ired overall Concentration during the initial fitDges of the reaction and gradually ~15~193 0,895 increased to greater than the desired overall concentration during the final stages. Methods for varying the relative m~n~mer concentr~tions in the feed Rtream are known and described in U.S. 3,804,881.
The concentration of the catalyst can vAry from about 0.001 to about 5 percent, preferably from about 0.2 to about 0.5 percent; however, any effective catalytic , nmount is satisfactory. Illustrati~e catalysts are the well-known free radical type of vinyl polymerization cata-lysts, for example, the peroxides, persulfates, perborates, percarbonates, az~ compounds, etc., including hydrogen per-oxide, dibenzoyl peroxide, acetyl peroxide, benzoyl hydro-peroxide, t-butyl hydroperoxide, di-t-butyl peroxide, laur-oyl peroxide, butyryl peroxide, diisopropylbenzene hydroper-oxide, cumene hydroperoxide, diacetyl peroxide, di-alpha-cumyl peroxide, dipropyl peroxide, diisopropyl peroxide, isopropyl t-butyl peroxide, butyl t-butyl peroxide, dilauroyl peroxide, difuroyl peroxide, ditriphenylmethy peroxide, bis(p-methoxy-benzoyl) peroxide, rubrene peroxide, ascaridol, t-butyl peroxybenzoate, t-butyl peroctoate, diethyl peroxyterephtha-late, propyl hydroperoxide, isopropyl hydroperoxide, n-butyl hydroperoxide, t-butyl hydroperoxide, cyclohexyl hydroperoxide, trans-decalin hydroperoxide, alpha-methylbenzyl hydroperoxide, tetralin hydroperoxide, triphenylmethyl hydroperoxide, diphenyl-methyl hydroperoxide, 2,2'-azo-bis(2-methylbutyronitrile), 2,2'-azo-bis~2-methylheptonitrile), l,l'-azo-bi~ cyclo-hexane carbonitrile), dimethyl alpha,alpha'-azo-isobutyrate, 4,4'-azo-bis(4-cyanopentanoic acid), azo-bisisobutyronitrile, per6uccinic acid, diisopropyl peroxy dicarbonate, and the like. A mixture of catalysts may also b2 used~
The temperature and c~taly~t are chosen ~uch that ~15gl93 10,895 the c~talyst has a satisfactory h~lf-life at the temperature employed; prefer~bly, the half life should be about 25 per-cent or less Gf the residence time in the reactor ~t the given temperature.
The polymerization can also be carried out with an inert organic solvent present. Illustrative thereof are toluene, benzene, acetonltrile, ethyl acetate, hexane, hep- , tane, dicyclohexane, dioxane, acetone, N,N-dimethylformamide, N,N-dLmethylacetamide, and the like, including those known in the art as being suitable solvents for the polymerization of vinyl monomers. The only requirement in the selection of the inert solvent is that it does not interfere with the polymerization reaction. When an inert organic solvent is used, it is preferably rem~ved by conventional means.
If desired, the improved polymer/polyols of this invention can be diluted prior to their use in the production of polyurethanes by adding thereto additional organic polyol.
The seeds level of the resulting polymer/polyol, as determined by the test described hereinafter, should ~e kept ~s low as possible. ~referably, the 150 mesh seeds should be no more than about 20 mg/100 g of polymer/polyol seed levels of 5 mg/100 g of polymer/polyol or e~en less are, of course, more preferred.
This invention also provides novel p~lyurethane products which are produced by reacting: (a) a polymer/
polyol composition of this invention, (b) an organic poly-isocyan~te, and (c) a cataly6t for the reaction of ~a) and Ib) to produce the polyurethane product, and, when a ~oam is being prepared, a blowing agent and a foam ~ta~ilizer. When the polyurethane i8 ~ ~olid or micr~cellular elastomer, the reac~ion mixture can also contain chain extender~. ~he ~59193 10,895 reaction and foaming operations can be performed i~ any suitable manner, preferably by the one-shot technique.
The organic polyisocya~ates that are useful in producing polyurethanes in accordance with this invention are organic compounds that contaln at least two isocyanato .
groups. Such compounds are well known in the art of pro-ducing polyurethane foams. Suitable organic polyisocyanates include the hydrocarbon diisocyanates, (e.g., the alkylene diisocyanates and the arylene diisocyanates) as well as known ln triisocyanates and polymethylene poly(phenylene isocyanates).
As examples of suitable polyisocyanates are 1,2-diisocyana-toethane, 1,4 diisocyanatobutane, 2,4-diisocyanatotoluene, 2,6-diisocyanatotoluene, 1,3-diisocyanato-o-oxylene, 1,3-di-isocyanato-m-xylene, 1,3-diisocyanto-~-xylene, 2,4-diisocyan-ato-l-chlorobenzene, 2,4-diisocyanato-1-nitrobenzene, 2,5-di-isocyanato-l-nitrobenzene, 4,4'-diphenylmethylene diisocyanate;

3,3'-diphenylmethylene diisocyanatei and polymethylene poly-(phenyleneisocyanates) having the formula:

2~ ~ C~ ~

wherein x has an average value from 1.1 to 5 inclusive (preferably from 1.3 to 3.0).
The cataly~ts that are useful in producing poly-urethanes in accordance with this invention include:
terti~ry amines such a~ bis(dimethylaminD ethyl) ether, trimethylamine, triethylamine, N-methylmorpholine, 1 15919:~ lO,B95 N-et hylmDrpholine, N,N-dLmethylethanolamine, N,N,N',N'-tetramethyl-1,3-butane-diamine, triethAnolamine, 1,4-diaza~icyclot2.2.2]octane, pyridine oxide and the like, and organotin compounds such as dialkyltin salts of carboxylic acids, e.g. dibutyltin diacetate, dibutyltin dilaurate, dibutyltin maleate, dil~uryltin diacetate, dioctyltin diacetate, and the like. Sta~nous octoate i6 likewise a useful catalyst. Similarly, there may be u~ed a trialkyltin hydroxide, dialkyltin oxide, dialkyltin dialk-oxide, or dialkyltin dichloride. Examples of these com-p~unds include trimethyltin hydroxide, tributyltin hydroxide, trioctyltin hydroxide, dibutyltin oxide, dioc~yltin dichlor-ide, and the like. The catalysts are employed in small amounts, for example, from about 0.001 per cent to about 5 percent based on weight of the reaction mixture.
The blowing aqents useful in producing polyurethane foams in accordance with this invention include water and halogenated hydrocarbons such as trichloromonofluoromethane, dichlorodifluoromethane, dichloromonofluoromethane, dichloro-methane, trichloromethane, l,l-dichloro-l-fluroethane, 1,1,2-trichloro-1,2,2-trifluoromethane, hexafluorocyclobutane, octafluorocyclobutane, and the like. Another class of blow-ing agents include thermally unstable compounds which liberate gases upon heating, such as N,N'-dimethyl-N,N'-dinitrosotereph-thalamide, and the like. The generally preferred method of foaming for producing flexible foams i~ the use of water or a combination of water plu~ a fluorocarbon blowing agent such as tric~loromonofluoromethane. The quantity of ~lowing agent employed will vary wi~h factors such a~ the den~ity desired in the foamed product.

The fo~m 8ta~ilizer6 useful in producing polyurethane ~ ~59193 - 10,895 ¦ foams in accorda~ce with t~is invention lnclude ~ydrolyzable~
polysiloxane-polyoxy~lkylene block copolym~rs such ~5 the block copolymer6 described in U.S. ~atents 2,834,748 and 2,917,~80. Another useful class of foam 6ta~ilizer6 are the non-hydrolyzable~ polysiloxane-polyoxyalkyle~e ~lDck copolymers such as the bloc~ copolymer~ described in U.S.
Pat~nt 3,5Q5,377; U.S. Patent No. 3,68~,254 issued August 22, 1972, and British Patent Specification 1,220,471.
The extenders useful in produciny microcellular polyurethane elastomers in accordance wi~h this invention include aromatic polyamines and aromatic glycols. Illustra-tive of suitable hindered aromatic polyamines are 3-chloro-4,

4'-diaminodiphenylmethane, 4,4'-methylene bis (2-chlor~ani-line), cumene diamine, toluene diamine, and dichlorobenzidine.
Illustrative of the aromatic glycols are reaction products of alkylene oxides with aromatic amines or alcohols having two active hydrogens, especially reaction products of alkylene oxides with dithydroxyalkoxyl~ aryl compounds and prLmary amino aryl compounds. The preferred aromatic glycols are the reaction products of ethylene oxide and aniline. Other extenders that may be used include ethylene oxide and propy-lene oxide adducts of bisphenol A t~PLURACOL-P-245~) or the propylene oxide adduct~ of aniline (~C-100"). Still other u~eful extenders are butane diol, ethylene glycol, diethylene glycol, propylene glycol, dipropylene g~ycol, etc~
Polyureth~nes produced in accordance with t~is invention ~re useful in the ~pplications in which polyure-thanes m~de fro~ conventional polymer/polyol ~ompo~itions are employed. Indeed, the polyuretbane~ 80 producea may be utilized ~n foam and elastomer applications where ~ny con-ventional type of polyureth~ne ~8~ ~r can be, util~zed.

~ ~5~193 ( 10,895 The Examples which follow are intended to further illustrate the invention described herein and Are not intended to l~mit the invention in ~ny w~y.

~EFINITIONS
As used in the Examples appearing below, the following designations, symbols, terms and abbre~iations have the indicated meanings.

Polyol I A polyether polyol produced by polymerizing propylene oxide with a glycerine starter to a hydroxyl number of about 40, stripping.the product, and reacting it with about 15 weigh~ percent ethylene oxide to reduce the hydroxyl number to about 34 to provide a nominal number average molecular weight of about

5,000.

Polymer Polyol I A conventional polymer/polyol produced by polymerizing a 52/48 weight ~ixture of acrylonitrile and styrene in situ in Polyol I, the amount of acryloni~ e and styrene being 21 weight percent of the total weight of Polyol I, acrylo-nitrile, and styrene.

Catalyst I A solution consisting of 70 weight per-cent bist2-dLmethylaminoethyl) ether and 30 weight percent dipropylene glycol.

Catalyst II A solution consisting of 33 weight percent triethylene diamine and 67 weight percent dipropylene glycol.

Catalyst III A solution consisting of 33 weight per-cent 3-diethylamino-N,N-dimethylpro-pionamide and 67 weight percent CgHlgC6H4 (OC2EI4) gOH
Silicone Surfact-~nt I Mixture of 86 weight percent ~lyol I
and 14 weight percent ~e3SiO~Me2SiO)4(MeSIiO)2 8~iMe3 ~3~6o(c2~4o)3Me '0,895 ~ 159:L93 Silicone Surfact-ant II Mixture of 70 weight percent polyoxy-propylene glycol; 10 weight percent Me35iO~Me25iO)2 6 (MeliO)1.4 30 weight percent Me3SiO(Me2SiO)4(MeSiO)2 8SiMe;
C3H6 (C2~40) 3Me ' Isocyanate I A mixture of 80 weight percent of an 80/20 weight mixture of 2,4-tolylene diisocyanate and 2,6-tolylene diiso-cyanate, and 20 weight percent p~ly-methylene polyphenylene isocyanate having a free NCO content of 31.5.
Isocyanate II Glycerine plus 3 moles propylene oxide reacted with toluene diisocyanate to a free NC~ content of 30 percent.
Extender Average composition of the reaction product of 2.3 moles ethylene oxide with aniline.
20 VCN Acrylonitrile MVCN Methacrylonitrile S S~yrene MA Maleic anhydride PETA Pentaerythritol triacrylate VAZO Azo-bis-isobutyronitrile EI Ethylene imine ILD Indentation Load Deflection CLD Compression Load Deflection pbw parts by weight 30 rpm revolutions per minute ~ percent cps centipoises mg milligrams g grams wt weight - ~159193 ( 10,895 in inch psig pounds per s~uare inch gauge Test Procedures The following test procedures were employed in the Examples to determine the indicated properties.

PC~LYOL PROPERTIES
150 Mesh Seeds. A 470 gram sample is diluted with 940 grams of isopropanol to reduce viscosity effects. The diluted sample is passed through a 2.4 square inch ~Standard Tyler~
150 mesh screen (average mesh opening 105 microns). The screen is washed with isopropanol, dried and weighed. The difference between the final and initial screen weight corres- -ponds to the amount of polymer which did not pass through the screen and is reported as milligrams per 100 grams of polymer/
polyol.

POLYURETHANE ~OAM PROPERTIES
Mold Exit Time. The isocyanate is mixed with the polymer/
polyol and other components of the polyurethane foam-forming composition at time Tl. The formulation is introducea into a preheated mold having vent holes at the top and the foam expands in the mold. At time T2 foam begins to exit through the vent holes. Mold Exit Time is the time elapsed ~rom ~1 to T2.
Air Porosity. A polyurethane foam ~pecimen 0. 5 .in. in thickness is compressed between two pieces of flangea plastic tubing having a 2. 25 in. internal di~meter. This assembly is then incorporated ~s a comp~nent in ~n air flow ~yst~m. Air at a controlled velocity enters one end of the tubing, flows ~ 1 59 193 10,895 through the foam ~pecLmen, and exit6 through ~ restriction at the lower end of the assembly. The pressure drop acros~ the foam due to the restriction of air passage is mea~ured by means of an inclined closed manometer. One end of the m~no-meter is connected to the upstre~m 6ide of the foam hnd the other end to the downstream ~ide. The flow of air on the up-6tream 6ide is adjusted to maintain a differential pressure across the specLmen of 0.1 inch of water. The air porosity of the foam is reported in ~nits of air flow per unit area of specimen (cubic feet per minute per square foot).
The following properties of the polyurethane foams were determined in accordance with ASTM D2406:

Indentation Load Deflection (ILD) Compression Set Tensile Strength Elongation ~ear Resistance Load Resistance Load Ratio Resilience Compression ~oad Deflection (CLD) ~ Return The following ASTM procedures were employed to determine the indicated properties for the solid polyurethane elastomers:
Bardness D-2240 Tensile Modulus D-412 Tensile Strength D-412 Elongation D-412 Die ~C~ Tear D-624 Examples 1-26 A series of polymer/polyol~ were prepared ~y a ~emi-batch proces5. Examples C-l, C-2, and C-3, are compar-ative example~ of polymer/polyols which were prepared without ~ 1 59 193 C 10,895 the use of ~ny maleic anhydride in the monomer mixture.
In e~ch Example, except Example 24, there were initially charged t~ ~ stirred, 5-liter reaction fl~s~, 880 grams of Polyol I which was heated to 120~C. (initial charge of Polyol I in Example 24 being 968 grams). There w~re then fed to the flask, over a period of two h~urs, 646.4 grams (711.04 gr~ms in Ex. 24) of a solution of 20 p.b.w. of monomer mixture, 0.4 p.b.w. of monomer mixture, 0.4 p.b.w.
VAZO catalyst, and 20 p.b.w. Polyol I. The composition of the monomer mixture for each Example, in weight percent, is given in Table I. ~here were then added an additional 80 grams of Polyol I and 1.6 grams of ~AZO over a period of one hour, while maintaining the temperature of the reactants at 120C. (88 grams of Polyol I and 1.8 grams VAZO in Ex. 24).
Volatiles were stripped for one hour in a rotary evaporator at a pressure of about 1 mm. Hg. The ethylene imine employed in Ex. 25 and 26 was post-added as 3.3 grams of a 20 weight percent solution of ethylene imine in Polyol I.
In Examples C-2, 6, 7, 10, C-3, and 13-23, the solution of Polyol I, monomer mixture, and VAZO were ~imply premixed in a feed tank and fed to the reaction flaskc The remaining Examples employed a methcd of feeding the monomers in which the concentrations of the various mon-omers in the feed ~tream varied during the reactiDn. The process employed to vary the monomer concentration in the feed ~tream was as is described in U.S. 3,804,BBl.
Examples 2-5, 8, 9, 11, 25, and 26 employed ~ feed tan~ and an auxiliary feed tan~, the latter being referred to as ~Tan~ I~. The tanks were arranged 6uch that Tank I
fed into the feed tank, which in turn fed into the rea~tion vessel. The feed tank and Tank I were initially charged ~ 1 5~ 1 93 10,895 with the amounts of monomers, c~t~lyst, and P~lyol I which are indicated in Table I. Amounts ~re indicated in grams.
The feed from Tank I int~ the feed tank and th~
feed from the feed tank t~ the reaction ~essel were commenced simu1taneDusly. ~he feed rates ~ere constant and were se1ected so that the feed tank and Tank I emptied simultan-eously. Typically, the contents of ~ank I were fed into the feed tank ~t a rate of 161.6 grams/hr.; and the contents of the feed tank were fed to the reaction vessel at a rate 10 of 323.2 grams/hr. The feed tank was stirred 50 as to provide rapid mixing of the incoming feed from Tank I with the contents of the feed tank.
Examples C-l, 1, and 24 employed a variable mon~mer content feeding arrangement similar to that of 2-5, etc., except that two auxiliary feed tanks, Tank I and Tank II, were employed. The initial charges of material io the feed tank, ~ank I, and Tank II, are given, in grams, also in Table I. The feed from Tank I to the feed tank was commenced simultaneously with the feed from the feed tank to the reaction vessel. The feed rate of ~ank I w~s such that it was emptied after one hour. The feed from Tank II
into the feed tank was then immediately commenced at a rate such that Tank II emptied at the same time as the feéd tank.
~n Example 24, there was fed to the reaction vessel from a dropping funnel, prior to beginning the feed from the feed tank, an initial feed mixture containing 25.6 grams acrylonitrile, 6.4 grams styrene, 0.64 grams VAZ0, and 32 gram6 Polyol I. The initial feed took place over 15 minutes; thu~, total feed time for Example 24 was 30 2:15 hours.
Example 12 employed a single auxiliary tank ~159193 ln, 895 in Examples 2-5, etc.;, however, the feed from Tank I into the feed tank was not begun until half the contents of the feed tank had been fed to the reaction vessel. The feed rate from Tank I into the feed tank was such that the two tanks emptied simultaneously. The parts ~y weight of the reactants i5 also set forth in Table I.

. ~

~ 159193 o ~ ~ o I ~ ~ D
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~1591g3 10,895 The viscosity, filterability and other character-istics of the polymer/polyols so produced are set forth in T~ble II below.

~159:L93 o o o ~o C~ _, - ,1U- I ~U I I ~ o O I ~ ~,, I I'` ~ O

I _l I I ~ U~ I O

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r7 1 1 ~ O
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568 ' OT

~ 1 S9 193 10,895 As can be seen from Table II, by a comparison of control example C-l with Example 1 and control C-2 with Examples 6 and 7, respectively, (the examples which are considered directly comparable) the polymer~polyols formed in accordance with the present invention have slightly lower viscosities and equivalent filterability characteristics in comparison to the polymer/polyol controls.
Also, the filterability characteristics of the polymer/polyols of Examples 13-15 and 22-23 compare satisfactorily with the polymer/polyol of C-3. The viscosity characteristics of these Examples are higher than that of the C-3 polymer/polyol but are considered to be within the same general range with the exception of the Example lS
polymer/polyol.

Examples 27-28 Using various polymer/polyols from t.he previous Examples and controls, a series of molded, high resiliency polyurethane foams were produced. Additionally, a molded polyuret.hane foam was prepared usinq Polymer/Polyol I, the conventional polymer/polyol previously described.
Each polyurethane foam was produced using one of two reactive formulations, ident.ified as A and B in Table III.

1 15~193 - 10, 895 TABLE I I I
FGRMULATIONS FOR MOLDED, HIGH RESILIENCY ~OAMS

Components, parts by weight A B
Polyol I 60 60 Polymer-Polyol 40 40 Water 2.6 2.6 Catalyst I 0.11 0.10 Catalyst II 0.33 0.36 Catalyst III 0.25 0.30 Silicone Surfactant I 1.5 --Silicone Surfactant II -- 0.75 Polyis~cyanate Index 105 105 Tin Cat.alyst .02 .015 The molded polyurethane foams were prepared in the following manner. A mold tl5 in. x 15 in. x 4.75 in.) was waxed with a mold release aqent (Perma-Mold Release Agent 804-7 SH, supplied by Brulin) and heated t.o 170 to 200F. in a dry air o~en. Excess mold release agent was wiped off, and the mold was cooled to about 120F. The polyisocyanate was weighed into one beaker, and the water and amine catalyst were weighed int.o a separa~e beaker. The polyols, tin catalyst and silicone. surfactant were weighed into aØ5 gallon cart.on and placed on a drill press. The polyol was mixed for 30 seconds with a 2.5-inch, 6-blade turbine at 400 r.p.m. The ~ixer was stopped, the water/~mine mixture was added, ~nd a ~ixing baffle was pla~ed in the carton. ~ixing was then resumed for S5 6econds, after which the polyisocyanate was added;

~159193 10,895 mixing was ~till further resumed for another S seconds. The contents of the carton were poured into the heated mold.
After 2 minutes the mold was placed in an oven at 250DF
for 6 minutes. The foam was then removed from the mold, crushed by hand, and passed through a roller 3 times. .
~he properties of the foams were then determined, as set forth in Table IY. The humid aged foam prope~ties set forth in , Table IV were determined by placing the foam specimen in a steam autoclave for 5 hours at 120C. at 12 to 16 p.s.i.g.;
drying for 3 hours at 70~C. in a convected dry air oven; and equilibratinq for 16 to 2~ hours at 23C. and 50~ relative humidity.
Polyurethane foams could not be successfully prepared from the polymer-polyols of Examples 7 through 13 and 15 through 19 using standard formulations, presumably due to the apparently hish acid numbers, believed responsible for the foam collapse. However, these polymer/polyols are considered suitable for use in the production of solid or microcellular polyurethane elastomers. Formulation modifi-cations may also have obviated the collapse of these foams.

~59193 10,895 ~BLE IV

Example K-l 27 28 29 Polymer/Polyol (Ex3mple No.) C-3 22 23 14 Mbnomer Composition Acrylonit~ile 80 80 76.9 75 Styrene 20 16.9 20 20 Maleic Anhydride - 3.1 3.1 5 F~am Form~lation (Table III) B B B B
Foam Physical Properties Density, o~erall, 2.95 2.95 2.94 2.97 Lb./ft.
core, lb./ft.3 2.69 2.78 2.78 2.68 Air P~r~sity, ft /min~ft2 5.1 45.5 48.3 14.2 Resiliensy, ~ ~all rebound 56 64 65 61 ILD (Lbs/50 in2) 25% 38.5 41.8 41.9 44.9 65% 102.0 108.0 107.5 115.0 25% Return, ~ 81.8 81.2 81.4 83.5 Load Ratio 2.65 2.58 2.56 2.56 25%~a) 39.1 42.9 42.8 45.4 65%(a) 103.7 111.0 109.? 116.2 Tensile Strength, psi 23.5 18.8 21.1 22.3 Elongation, % 147 138 153 144 Tear Resistance, pli 1.81 1.63 1.52 1.91 754 Compression Set, Cd,% 10.2 7.9 7.1 6.D
Humid Aqing ~5 hrs at 120C.) 50% Compression 5et, Cd,% 25.6 24.2 22.5 20.3 50% CLD Load LDSS, ~ 28.1 23.1 25.5 36.0 (a) Normalized to 3.00 lb./ft3 density.

~0-~ 1 59 193 10,895 ~IE IV (Continu~l) Example K-2 30 31 32 Polymer-Poly~l tEXample No.) ~ 20 21 6 Monomer Composition S
Acrylonitrile 52 50 46.9 50 Styrene 48 46.9 50 45 Maleic Anhydride -- 3:1 3.1 5 Foam FormLlation tTable III) B B B B
Foam Physical Properties Density, overall lb./ft.3 2.92 2.98 2.98 2.97 core, lb./ft.3 2.57 2.77 2.82 2.81 Air Porosity, ft3/min/ft2 10.6 45.5 43.3 42.5 Resiliency, % ~all rebound 58 63 64 68 ILD tLbs/50 in ) 2S% ~ 37.7 43.2 43.0 42.1 65% 96.4 109.2 110.0 108.3 25% Return, % 81.5 81.0 80.7 82.9 Load Ratio 2.56 2.S3 2.56 2.57 25%(a) 38.7 43.5 43.3 42.5 65%(a) 99.0 109.9 110.7 109.4 Tensile Strength, psi 23.5 23.1 23.2 20.2 Elongation, % 163 154 146 132 Tear Resistance, pli 1.77 1.71 1.78 1.59 75% Compression Set, Cd,~ 10.5 7.8 8.6 7.5 Humid Aging (5 hrs at 120C.) 50~ Compression Set, Cd,% - 23.5 22.6 23.8 20.7 50%CLD Load Loss, % 16.3 22.2 21.8 35.0 *Polymer/Poly~l I
~a) Normalized tD 3.00-pcf density.

~ 1 59~ ~3 10,895 TABLE IV (Co~tinu~l) Examp~e _ 34 35 36 Polymer/Polyol (Example No.) 2 3 4 5 Mbnorer C ~osition Methacrylonitrile 75 74 70 65 StyrEne 20 20 20 20 Maleic Anhydride 5 5 5 5 Pentaerythritol Triacrylate Acrylonitrile - - 5 10 Foam FormLlation (Table III) A A A A
Foam Physical Properties Density, ~verall, Lb./ft 2.99 3.01 3.02 2.99 core, lb./ft3 2.76 2.60 2.58 2.61 Air Porosity, ft3/min~ft2 34 0 26.1 23.0 26.7 Resilien~y, 4 ball rebound 67 63 65 65 ILD (Ibs/50 in2) 25% 38.7 42.0 41.0 38.7 65% 103.0 106.2 106.3 106.5 25% ~eturn, 4 84.5 83.1 83.9 83.5 Load Ratio 2.66 2.53 2.59 2.75 254(a) 38.8 41.9 40.7 38.8 65%(a) 103.3 105.8 105.6 106.9 Tensile Strength, psi 21.8 22.5 21.3 22.4 Elongation, % 146 163 154 149 Tear Resistance, pli 1.77 1.97 1.94 1.92 75~ Ocmpression Set, Cd, % 7.6 7.9 7.8 8.5 Humid Ay~ng (5 Hrs at 120C.) 50% Compression Set, Cd,% 18.3 18.5 18.7 21.9 50% CLD Load hoss, 4 29.1 27.5 25.7 28.6 (a)Normali~ed to 3.00 lb./ft.3 overall density.

~ 10,895 ~159~93 I~ELE IV tContinufd) Example X-3 37 R-4 38 PolymerfPolyol tExamPle No.) C-l 1 C-l Mbncner Composition Methacrylonitrile 75 70 75 70 Styrene 25 25 25 25 Maleic Anhydride - 5 - 5 FDam ~ormLlation tTable III) A A B B
Fbam Physical Propertie~
~ iensity, overall3 lb/ft.3 3.05 3.12 2.97 2.96 core, lb./ft. 2.38 2.57 2.57 2.53 Air Porosity, ft3/min~ft2 7.7 7.9 23.5 17/2 Resiliency, % ba211 re~ound 55 57 62 63 ILD tl~;./50 in ) 254- 38.0 53.4 41.9 49.0 65~ 88.0 115.0 96.0 111 5 25% Return, % 83.9 83.1 84.7 85.1 Load Ratio 2.31 2.15 2.29 2.27 25%(a) 37.4 S1.3 42.3 49.7 65%(a) 86.6 110.6 97.0 113.0 Tensile Strength, psi 17.4 14.4 21.9 18.0 Elongation, 4 137 102 154 128 Tear Resistanc~, pli 1.86 1.62 1.83 1.79 75% Compression Set, Cd% 7.6 6.0 8.3 7.0 Humid AgLng (5 hrs at 120C) 50% Ccmpression Set, Cd,% lB.3 14.7 19.1 18.1 504 T~ T~A~ Loss, % 27.3 27.1 29.1 31.5 ~a)Nornali2ed to 3.00-pcf density 10,895 ~39 i9 3 A~ can be ~ee~ from M comp~ri~o~ of Example K-l (reporting a foam prep~red from polymer/polyol control C-3) with Examplos 27-29 (made frDm the polymer/polyols of Examples 22-23 and 14, re~pe~tively, the normalized 25~ and 65~ ILD
values are ~ignificantly higher for the foams m~de from polymer/polyols in accordance with this invention. ~$mil~rly, the Compres~ion Set v~lues for these foams are superior, being significantly lower than the value for the R-l control foam.
These same improvements in load bearing capacities ~re evi-dent from a compariSGn of Example R-3 (made from eontrol polymer/polyol C-l with foam formulation A) with the Example 37 foam and Example X-4 (made from control polymer/polyol C-l with foam formulation B) with the Example 38 foam. The ComFression Set values for the foams made in accordance with this invention are slightly better, but are probably not sufficiently lower than the value of the control foam 80 as to be truly significant. W~.ile the foam of Example R-2 i5 not strictly comparable with the foams of Examples 30-32 since a commercially available polymer/polyol was used, the tendency towards improved load-bearing and Compre~sion Set characteristics is evident.

Ex~mple 39 This Example illustrates the preparat~on of ~
polyureth~ne elastomer from a polvmer/polyol in accordance with the present invention. The properties of the resulting elastcmer were then ~mpared to an elastomer forme~ from a c~ntrol elastomer.

~ and cast, urethane elastomer~ were thu5 made from the monomer mixtures ~et forth in Table V as follows.
The polymer/polyol, extender ~nd tin cat~lyfit ~0.03 parts) ~ 1~91~3 D-10,895-C

were mixed in a reaction flask, the amounts of extender and polymer/polyol being set forth in Table V, consisting of a 500 ml., 4-necked, round-bottom flask equipped with mechanical stirrer, vacuum inlet stirrer, and heating mantle. The flask was attached to a vacuum pump and was degassed for about 20 minutes, the isocyanate to be used also being degassed. The required amount of isocyanate as also set forth in Table V hereinafter, was then added to the reaction flask, after the stirrer had been stopped and the vacuum broken. The vacuum is then reapplied, and the stirrer started. The mixture was stirred vigorously for about 15 seconds or somewhat more.
The vacuum was then broken, and the liquid elastomer system contained in the flask was poured between two glass plates coated with a Hysol TM mold release agent "AC-4368" (Dexter Corp.) and spaced apart by a poly-tetrafluoroethylene spacer to provide a gap of about l/2 inch to facilitate pouring. The mold was clamped securely around its perimeter using the spring clamps and placed in an oven for curing.
The results are set forth in Table V, hereinafter.
As seen, the elastomer made according to the present invention exhibits improved tensile modulus as well as tear.

45.

~ ~5~93 10,895 TABLE V

Polymer Polyol (Ex. No.) C-l Monomer Composition S 2'5 25 ~`

Elastomer Components Equivalent Ratio Polymer/Polyol 1.0 1.0 Polyol ~xtender 1.0 1.0 Isocyanate II 2.1 2.1 Elastomer Properties Hardness, Shore A 62 62 100~ Tensile Modulus, p.s.i. 287 303 Tensile Strength, p.s.i. 421 389 Elongation, % 137 122 Tear, Die C, p.l.i. 67 92 ~15~193 10,895 Thus, as has been seen, the present invention provides polymer/polyols which can be readily prepared hnd which impart improved parties to polyurethane products made therefrom without any accompanying substanti~l increase in ~' viscosity of the polymer/polyol. Polyuret.hane fo~m6 exhibit improved load-bearing and compression set properties while elastomers possess improved tensile modu~us and tear proper- ,~
ties i.n comparison t.o conventional polymer/polyols.

_~7_

Claims (19)

10,895 WHAT IS CLAIMED IS:

1. A fluid, stable polymer/polyol which comprises:
(1) from about 60 to about 90 weight percent of an organic polyol medium consisting essentially of at least one normally liquid polyol and (2) from about 10 to about 40 weight percent of an interpolymer of (a) a minor amount of polymerized ethylenically unsaturated dicarboxylic acid anhydride and (b) a major amount of at least one different polymerized ethylen-ically unsaturated monomer, said interpolymer being in the form of particles that are stably dispersed in the polyol and said weight percents being based on the total weight of the polymer and polyol.

2. The polymer/polyol of claim 1 wherein said polymerized ethylenically unsaturated dicarboxylic acid anhydride is present in an amount of from about 0.5 to about 20 weight percent based upon the total weight of the interpolymer.

3. The polymer/polyol of claim 2 wherein said polymerized ethylenically unsaturated dicarboxylic acid anhydride is present in an amount of from about 0.5 to about 10 weight percent.

4. The polymer/polyol of claim 2 wherein said polymerized ethylenically unsaturated dicarboxylic acid anhydride is present in an amount of from about 2.5 to about 6 weight percent.

5. The polymer/polyol of claim 1 wherein said ethylenically unsaturated dicarboxylic acid anhydride is maleic acid.

6. The polymer/polyol of claim 1 wherein said different polymerized ethylenically unsaturated monomer consists of acrylonitrile and styrene.

10,895

7. The polymer/polyol of claim 1 wherein said normally liquid polyol consists of a poly(oxypropylene) polyol.

8. The polymer/polyol of claim 1 wherein said polymer/polyol contains a seed level of less than about 20 mg/100g polymer/polyol.

9. The polymer/polyol of claim 8 wherein the seed level is less than about 5 mg/100g polymer/polyol.

10. A process for producing a fluid, stable polymer/polyol which comprises polymerizing, in the presence of a free radical catalyst, (1) from about 10 to about 40 weight percent of a monomer mixture of (a) a minor amount of an ethylenically unsaturated dicarboxylic acid anhydride and (b) a major amount of at least one different ethylenically unsaturated monomer, dispersed in (2) from about 60 to about 90 weight percent of an organic polyol medium consisting essentially of at least one normally liquid polyol, said weight percents of the monomer mixture and polyol medium being based on the total weight of the monomers and polyol medium.

11. The process of claim 10 wherein said ethylen-ically unsaturated dicarboxylic acid anhydride is present in an amount of from about 0.5 to about 20 weight percent, said weight being based on the total weight of said monomer mixture.

12. The process of claim 11 wherein said ethylenic-ally unsaturated dicarboxylic acid anhydride is present in an amount of from about 0.5 to about 10 weight percent.

13. The process of claim 11 wherein said ethylenic-ally unsaturated dicarboxylic acid anhydride is present in an amount of from about 2.5 to about 6 weight percent.

10,895

14. The process of claim 10 wherein said ethylen-ically unsaturated dicarboxylic acid anhydride is maleic anhydride.

15. The process of claim 10 wherein said different ethylenically unsaturated monomer consists of acrylonitrile and styrene.

16. A method for producing an elastomeric poly-urethane which comprises reacting a mixture comprising: (a) a polymer/polyol composition as claimed in claim 1, and (b) an organic polyisocyanate in contact with (c) a catalyst for the reaction of (a) and (b) to produce a polyurethane.

17. The elastomeric polyurethane produced by the method of claim 16.

18. A method for producing a polyurethane foam which comprises reacting: (a) a polymer/polyol as claimed in claim 1, and (b) an organic polyisocyanate in contact with (c) a catalyst for the reaction of (a) and (b), (d) a blowing agent, and (e) a foam stabilizer.

19. The polyurethane foam produced by the method of claim 18.