WO1991018043A1

WO1991018043A1 - Hot melt adhesives based on ethylene terpolymers

Info

Publication number: WO1991018043A1
Application number: PCT/US1991/002840
Authority: WO
Inventors: Ernest Francis Eastman; Robert Joseph Statz
Original assignee: E.I. Du Pont De Nemours And Company
Priority date: 1990-05-17
Filing date: 1991-05-01
Publication date: 1991-11-28

Abstract

Terpolymers of ethylene with such monomers as an alkyl acrylate and carbon monoxide are blended with 5 to 80 % of a compatible tackifier to produce thermally stable hot melt adhesives which adhere to a wide variety of substrates, and which are suitably fluid for use in common low shear hot melt adhesive applicators. Plasticizers and compatible waxes may also be present in the adhesives.

Description

TITLE HOT MELT ADHESIVES BASED ON ETHYLENE TERPOLYMERS BACKGROUND OF THE INVENTION 1. Field of the Invention: This invention relates to hot melt adhesives, and more specifically it relates to such adhesives formulated from terpolymers of ethylene, an alkyl acrylate or alkyl vinyl ether and carbon monoxide or sulfur dioxide.

2. Description of Prior Art

Various copolymers of ethylene are known for use in hot melt adhesives. The most widely known and used of these are copolymers with vinyl acetate of varying viscosities and vinyl acetate contents. Ethylene vinyl acetate methacrylic acid copolymers have also been disclosed for adhesive use. Other ethylene copolymers such as ethylene with an acrylic acid and ethylene maleic anhydride are also known for this use. Ethylene vinyl acetate copolymers are not particularly thermally stable as application temperatures exceed 350°F (177°C) due to the vinyl acetate moiety. More stable ethylene copolymer adhesives have been disclosed. Ethylene butyl acrylate copolymers are described in US Pat. No. 4,816,306 to Brady et al. , which show 'superior aesthetic and heat stability properties when compared with similarly formulated blends of ethylene vinyl acetate copolymers'. Better melt stability and low temperature properties of these polymers is described also in an article in 'Adhesive age', November 1989, where an ethylene/n-butyl acrylate adhesive formulation maintained its fluidity better at 350 deg. F (177 deg. C) , and also could be processed at 100 deg. F. higher. Carbon monoxide has been polymerized with ethylene and vinyl acetate or an alkyl acrylate to produce ethylene vinyl acetate carbon monoxide and ethylene alkyl acrylate carbon monoxide terpolymers. Such polymers are disclosed in US Pat. No. 3,780,140 to Hammer as a plasticizer, to make polymer blends with PVC.

US Pat. No. 4,434,261 to Brugel et al. discloses a hot melt adhesive sheet which is self supporting at application temperatures of 200-350°F (94-177°C) which as such can be cut and formed to configure to adherends. The sheets are distinguished from 'conventional hot melt adhesives which must be applied in molten form as a premelted hot fluid'. The self supporting nature of the sheet is achieved by adding 20 to 80% of a filler (most preferably 50 to 60%) in combination with 2 to 30% of a plasticizer (preferably 12 to 18%) to any of a variety of ethylene copolymers. Ethylene/vinyl acetate is exemplified as the polymer component. Among the many other ethylene copolymers disclosed but not exemplified are terpolymers with either vinyl acetate or alkyl acrylate and carbon monoxide or sulfur dioxide. The sheets are disclosed as being capable of being laminated to fabric like structures, notably spun bonded polyester and spun bonded polypropylene.

US 4,600,614 to Lancaster et al. discloses multi-ply microwave film wrapping, wherein two plies of the same 'radiation sealable material' are in sealable contact with each other. The radiation sealable material may be any of a large number of copolymers and terpolymers which must contain from .01 to 50 wt. % of carbon monoxide. The carbon monoxide renders the polymer heatable by high frequency electromagnetic radiation (microwave energy) . If a termonomer is present it may be vinyl acetate, acrylic or methacrylic acid or its esters or salts.

US 4,601,948 to Lancaster et al. discloses novel terpolymers which may be used as hot melt adhesives. They are terpolymers of ethylene, carbon monoxide and acrylic or methacrylic acid, the latter two components being in the range of 1 to 40 wt.% each. The acid is in the formOf free acid, and not esters of the acid. Ethylene/methacrylic acid copolymers are well known for use in hot melt adhesives.

Japanese laid open patent application No 2-73828 assigned to du Pont-Mitsui (published March 13, 1990) discloses high performance adhesives of nylon grafted ethylene butyl acrylate carbon monoxide terpolymers. In that application, use of the terpolymers alone is shown in comparative examples to have deficient high temperature bonding performance.

There still remains a need for a thermally stable hot melt adhesive that has wide applicability with respect to the type of adherend and hence end use, and which is applicable using a wide variety of common economical low shear hot melt application equipment.

SUMMARY OF THE INVENTION The present invention satisfies this need by providing a thermally stable adhesive composition that may be used for adhering to a wide variety of adherends such as metals, polar and non polar plastics as well as wood and paper products, and may be applied in an economical way using common low shear hot melt adhesive application equipment. That is to say, the adhesive composition when heated for application as a hot melt adhesive takes the form of a molten fluid which is too fluid to be extrudable, or be self supporting, but ideally suited for conventional hot melt application. Accordingly, one embodiment of the present invention provides thermally stable hot melt adhesive compositions which are fluid at application temperatures, consisting essentially of ethylene 5 terpolymers containing about 40 to 87 wt. % of ethylene, about 10 to 50 wt.% of an alkyl acrylate or alkyl vinyl ether, and about 3 to 30 wt% of carbon monoxide or sulfur dioxide, the wt. %'s being based on the weight of the terpolymer, and about 5-80 wt% of a

10. compatible tackifier based on the weight of the terpolymer plus tackifier. Plasticizers and a compatible wax may optionally be present in the compositions.

Another embodiment of the invention is the

15 process of applying adhesive compositions of the present invention at elevated temperatures to transform the composition to a molten fluid, to any adherend selected from the group consisting of metals, polar and non-polar plastics, and wood and paper

20 products, and while said composition applied to said adherend is in a molten fluid form, contacting the applied composition with a second adherend, and cooling the resultant composite structure.

DETAILED DESCRIPTION OF THE INVENTION

25 The terpolymer component of the adhesive compositions of the present invention provides the cohesive and adhesive strength and thermal stability to the composition.

Alkyl acrylate or alkyl vinyl ether can be

30 considered the second monomer of the terpolymer.

Examples of the alkyl acrylate are those in which the alkyl group contains from 1 to 8 carbon atoms. Such examples include alkyl acrylates and methacrylates, such as methyl acrylate, ethyl acrylate, isobutyl

35 acrylate, n-butyl acrylate, 2-ethylhexyl acrylate and the corresponding methacrylates.

Second monomers which lower the glass transition temperature of the terpolymer will tend to make the terpolymer lower in viscosity for a given molecular weight, and ensure a tougher stronger polymer at ambient and moderately low temperatures. n-Butyl acrylate is especially useful in this regard and therefore is a preferred second monomer. At least about 10% by wt. of the terpolymer should consist of the alkyl acrylate monomer so that the adhesive composition can develo strong adhesive bonding. The maximum amount of acrylate monomer is generally dictated by the maximum amount which is polymerizable with ethylene and the third monomer. Generally, this maximu amount is about 50% by wt.

The alkyl vinyl ether as the second monomer preferably contains from 1 to 8 carbon atoms in the alkyl group and can be used as an alternative to the alkyl acrylate comono er, imparting the same characteristics to the adhesive composition as the alkyl acrylate. Examples of alkyl vinyl ethers include methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether, n-butyl vinyl ether, 2-ethylhexyl vinyl ether.

As compared to vinyl acetate, the alkyl acrylate and alkyl vinyl ether monomers provide greater thermal stability to the composition. The adhesive compositions of the present invention, and hence the polymers used therein need foremost to have adequate thermal stability at temperatures where the polymer is fluid enough to be applied with hot melt equipment. Stability requirements are generally more stringent than those required for an extrudable or preformed adhesive, since often extended hold up times at application temperatures are involved.

The carbon monoxide or sulfur dioxide comonomer component can be considered the third monomer of the terpolymer. This comonomer enhances the adhesive versatility of the terpolymer and thus the composition, enabling it to adhere to a wide variety of adherends. At least about 3% by wt. of the terpolymer should be carbon monoxide or sulfur dioxide to provide this versatile effect. These termonomers are^"polar, and this polarity imparted to the terpolymer enables the adhesive composition of the present invention to adhere to polar as well as non-polar plastic adherends. Greater than about 30% by wt. of these termonomers in the terpolymer can adversely affect the thermal stability of the terpolymer.

The third monomers used herein essentially destroy the thermal stability of ethylene vinyl acetate terpolymers containing CO or SO₂, even with the presence of antioxidant. Surprisingly, the terpolymers of the present invention have far superior thermal stability, enabling them to achieve advantageous utility in hot melt adhesive compositions applied as adhesives- in the molten fluid state. One aspect of thermal stability is resistance to oxidation by the composition while being held in the fluid state at application temperatures.

Preferred adhesive compositions of the present invention consist essentially of terpolymers containing about 45 to 80 wt. % of ethylene, about 10 to 40 wt. % akyl acrylate, and about 3 to 20 wt. % of carbon monoxide, based on the weight of the terpolymer, and about 30 to 80 wt. % of tackifier, based on the weight of terpolymer plus tackifier. The polymeric components of the present invention may be prepared by the method described in U.S. Patent 3,780.140, which is hereby incorporated herein.

The tackifier component can be selected from a wide variety of materials, such as follows: a) Wood gum or tall oil rosin acids. They can be hydrogenated, disproportionated or mildly polymerized. b) Esters of the various classes of rosin acids referred to above. Alcohols suitable for preparing these esters include mono- and polyethylene glycolε, glycerol, pentaerythritol and related products. c) Terpene resins d) Dicyclopentadiene-aromatic hydrocarbon resins such as those described in US Pat. No. 3,023,200 covering 'Piccovar' resin manufactured by Hercules Inc. e) Low molecular weight resins based on styrene and or substituted styrenes.

The tackifier is selected to be compatible with the terpolymer component. This compatibility is obtained by the terpolymer and tackifier being miεcible with one another in the molten state. Upon cooling to room temperature the composition compatibility within the composition is observable by the composition being both clear, not hazy, in appearance and flexible rather than brittle.

The proportion and identity of the tackifier is selected to cooperate with the terpolymer to produce the fluidity desired at the hot melt application temperature, generally falling within the range of about 250 to 400°F (121 to 204°C) . Fluidity of the adhesive compositions of the present invention are described herein in terms of viscosity measured as Brookfield viscosity at 350°F (177°C) . The low viscosities required for the adhesive compositions of this invention can be achieved either by starting with a relatively high viscosity terpolymer, and reducing the viscosity to the required level with a considerable amount of tackifier and optionally compatible plasticizers and/or wax or by starting with much lower viscosity terpolymer and using less tackifier. The viscosity of the terpolymer can be described in terms of melt index. The melt index of the terpolymer component may be from 1 to 3000 g/lOmin. measured at 190° C. The viscosity of the hot melt adhesive composition of the present invention. should be at least about 1000 cpε at 177°C and generally need not.be greater than 50,000 cps at 177"C. These viscosities correspond approximately to a melt index of about 10,000 to 200g/10 min.

While reducing molecular weight of the terpolymer component reduces its viscosity, this is accompanied by decreasing strength in the terpolymer itself. However, this means that less low molecular weight viscosity diluent (tackifier, and optionally plasticizer and/or wax) may be required in formulation. The strength of the final formulation is usually a compromise between the viscosity of the terpolymer component and the amount of tackifier and plasticizer, if any, used. Using an excessively high molecular weight terpolymer, and formulating to reduce the viscosity with an excessive amount of compatible tackifier, and plasticizer or wax can lead to a composition with deficient cohesive strength. At least about 20 wt % of terpolymer, is required for the composition to have adequate strength properties.

The compositions of the present invention may also contain compatible plasticizer and/or compatible wax for the purpose of adjusting the fluidity of the composition at the application temperature and other properties of the adhesive and in the application equipment being used.

Generally, tackifiers tend to be more glassy and may enhance tackiness in formulations, while plasticizers tend to be low molecular weight liquids with low glass transition temperatures. Examples of plasticizers which may be used in adhesive compositions of the present invention include phthalateε, azelates, adipates, tricresyl phosphate and polyesters such as those used in flexibilizing polyvinyl choride, low molecular weight resins made from alkylated phenols, phenol modified coumaroneindene, terpenes and synethtic terpernes, and from petroleum derived processing oils.

Compatibility with wax is normally considered important in formulating many hot melt adheεiveε, becauεe waxeε may provide an inexpenεive way to reduce viscosity, may contribute to some extent in improving resistance to temperature, reduce open time, or the time after application during which the polymer is sticky. This in turn leads to rapid application times. In addition, waxeε may promote wetting and prevent blocking. Paraffin wax, commonly uεed in hot melt adhesives, is generally not compatible with adhesive compositionε of the preεent invention with the desired versatility because of the polarity imparted to the terpolymer by the CO or SO₂ co-monomer. Other waxes, such as Carnauba wax, can be used in adheεive compositions of the present invention.

For varying applications, the adhesive formulator will choose among an enormous range of possible formulation components such as tackifier, and optionally wax and/or plasticizer and well as their levels in the composition. There are many guidelines available to help the formulator come up with a suitable composition for a given application. An excellent description of how these variables interact are provided in 'Hot Meltε- Yeεterday, Today and

Tomorrow', by Paul P Puletti preεented at an Adheεiveε Short Cours-e at the Adhesives and Sealant Council meeting in Cleveland, Ohio, in September, 1989, and published in the accompanying Adhesiveε Short Course Notebook. Thus, one skilled in adhesive formulation will arrive at suitable formulations which balance these variables, as well as adjusting to the economic conεtraints which the cost of different ingredients impose. In addition to the terpolymer used in the adhesive compositionε of the present invention, small amounts of copolymers such as (ethylene/vinyl acetate) or ethylene/alkyl acrylate or ethylene/methacrylic acid could be blended with the terpolymer component of the composition.

Antioxidantε are generally used in the formulation of ethylene copolymer hot melt adhesives, and it waε found that they were deεirable for best performance of formulations of the present invention. Suitable antioxidantε include typical hindered phenolε εuch aε butylated hydroxytoluene (BHT) , 'Ethyl'330, Ciba Geigy 'Irganox'1010 or 1098 aε well aε phosphites, butyl zi ate. 'Irganox' 1010 which is a hindered phenol has been found particularly advantageouε. When antioxidant iε uεed, it iε uεed in an amount which iε effective to provide the oxidative εtability deεired above and beyond the oxidative εtability of the terpolymer.

Adheεive compoεitionε of the preεent invention can be made by conventional melt blending of the ingredients to produce a miεcible melt. The melt can then be applied aε a hot melt adhesive. Used as such, the adhesive differs from εolvent-baεed adheεiveε because of the abεence of solvent and the adhesive-aiding effect of solvents. This iε reεponsible for the conventional hot melt adhesiveε being quite εelective aε to the εubεtrateε to which they will adhere.

The hot melt adhesives of the present invention, aε do conventional hot melt adheεiveε which are applied in the fluid state also face stringent requirements for thermal stability, including oxidative εtability. The hot melt adheεive componentε may be melt blended in a container and maintained in the heated, melt condition until applied aε an adheεive. When the melt of the formulated compoεition iε very viscous, well known equipment such aε a Brabender mixer, or a Perkinε Sigma blade mixer may advantageously be employed for the melt blending step. The time of maintaining the resultant composition in the molten state can depend on the size of the container and the rate the composition is applied as an adhesive. During thiε time, the composition may be exposed to the atmosphere and oxidation thereby. . Adhesive compoεitionε of the present invention are oxidatively stable aε well aε having stability from thermal degradation or they have sufficient thermal εtability that the uεe of antioxidant in the compoεition can provide the addition oxidative stability deεired.

The adheεive compositions of the present invention alεo differ from the extrudable self-εupporting sheetε diεclosed in U.S. Pat. 4,434,261 in that these sheets are heated only when applied as the adhesive, and therefore are not expoεed to the destructive effects of long-term heating, and not to heating to the* fluid or molten state at all. Surprisingly, the compoεitionε of the preεent invention provide a hot melt adhesive of outstanding versatility as a hot melt adhesive, in terms of application to a wide variety of adherents both polar and non-polar, and having adequate thermal stability εo aε to be useful to this purpose.

The adheεive compoεitionε of the present invention are applied in conventional manner for hot melt adhesives used in the fluid state. The adhesive composition is applied in the molten fluid form to the adherend, followed by contacting the adhesive composition still in the molten fluid εtate on the firεt adherent, with a εecond adherend, and cooling the reεultant composite structure to create the adhesive bond. The adherends will usually be at room temperature and the contacting step is usually done with the application of preεεure εufficient to obtain uniform diεtribution of the adheεive compoεition between adherend .

The adherendε or εubεtrateε which can be bonded together by adheεive compoεitionε of the preεent invention can be the same or different materials, such as metal, wood, paper, and polar and non-polar plaεticε. Examples of plaεticε include polyethylene, polyeεterε, including polycarbonate, polyacrylateε, including polymethyl methacrylate, polyεtyrene, polyvinylchloride, and ABS polymerε. Exampleε of metalε include aluminum and εtainleεε εteel.

EXAMPLES In the Exampleε, the procedure for making the adheεive compoεitionε teεted was as follows: small quantities of formulated adhesive were produced in a 1 pint paint can which waε placed in a heated block at 350 deg. F.(177 deg.C). The tackifier and anti-oxidant were added first, and after they were melted the terpolymer was added in slowly. The mixtures were stirred with an air driven motor using a three bladed commercial propeller agitator until the polymer was molten and fully dissolved.

The adheεion teεting in theεe Exampleε was carried out as follows: The substrates used were panels measuring about 3 x 1 x 1/4 in. The adhesives were tested using the so-called 'button test', which iε carried out in the following manner. Adheεive at about 177° C. waε applied to one εubstrate at room temperature, and then the εecond εubεtrate alεo at room temperature was placed on the adheεive, and the two εubεtrates pressed together using finger presεure. The two subεtrateε were preεsed together traversely so that the total bond area was about one square inch. After the adhesive had cooled and set, the bond waε tested by pulling apart the substrateε in an Inεtron tester at 0.5 inches/min. The force need to break the bonding waε recorded.

Thermal εtability was measured uεing a Brookfield viεcometer, model RVT, uεing a # 27 spindle. Viscosity was measured after various times in the viscometer. Oxidative εtability waε meaεured by allowing the adheεive compoεition to εtand in an open veεεel 2 in. in diameter in an air oven at about 177° C. for the times indicated. The vesεel waε filled with εufficient material εo that the melted material waε about 1/4 in. deep. The viscosity was then measured by transferring the cooled hot air exposed material to a Brookfield Viscometer, at 177° C.

In the further description of Examples of the present invention, hereinafter parts and percents are by weight unless otherwise indicated. Exampleε 1 - 10 and Comparative Exampleε Cl - C3.

In theεe Exampleε, the good thermal and oxidative stability of compoεitionε of the preεent invention and comparative formulationε iε illuεtrated. An antioxidant iε commonly uεed in ethylene copolymer hot melt adheεiveε. 'Irganox' 1010 waε uεed here. Thermal εtability reεultε are εhown in Table 1, and oxidative εtability in Table 2. Better stability of the terpolymer generally means better thermal εtability of the formulated adhesive, and this provideε more proceεεing verεatility. Exampleε 1 -4 εhow that formulationε uεing variouε terpolymerε of ethylene with acrylateε and carbon monoxide or sulfur dioxide are much more thermally stable than ethylene vinyl acetate carbon monoxide terpolymer which is unstable after just three hourε. In other wordε, the comonomer added to the EVA (Cl) juεt about deεtroyed the thermal εtability of thiε terpolymer, whereaε compoεitionε of the present invention in which the terpolymer contained CO were quite thermally stable. The composition of Example 1 had a relatively high viεcoεity. Thiε can be reduced by uεe of a greater proportion of tackifier, or a different tackifier which provideε greater fluidity at application temperatureε and/or by incorporation of compatible plaεticizer and/or wax into the compoεition. Exampleε 5 - 7 and C2 εhow that ethylene n-butyl acrylate carbon monoxide terpolymerε are surprisingly just as stable aε ethylene n-butyl acrylate polymer without any carbon monoxide. The carbon monoxide doeε not hurt thermal stability at thiε level, and, aε will be εeen in later exampleε, it improveε adheεive qualities. Examples 8 - 10 and C3 εhow the oxidative εtability of compoεitionε of the present invention. The presence of CO at the levelε indicated doeε not significantly affect oxidative εtability. Stability is as good as in the comparative example C3.

TABLE 1 THERMAL STABILITY (Formulations: . Examples 1 - 4 and Cl, 40 parts polymer, 60 parts Foral 105, 1 part 'Irganox' 1010. Exampleε 5 - 7 and C2, 35 partε polymer, 65 partε Foral 105, 0.2 parts 'Irganox' 1010) Ex# Resin Viscosity at 176 deg. C. , Centipoise x 10~²

(Wt.%) Initial 3Hr. 24Hr. 48Hr. 72Hr. 96Hr

1 E/iBA/CO

(54/37.4/8.6) 2000 2000 2920

2 E/MA/CO

(63.7/26.3/10) 105 102.5 190

3 E/EA/CO (51.6/31.9/16.5) 160 160 230

4 E/nBA/S02) (61.4/29.3/9.3) 95 93 90

(66/25/9) 38.6 42.6 50 68

E/nBA/CO (71/25/4) 44.6 56 59 58 65

C2 E/nBA (80/20) 37.2 45.5 49.1 53 55.5

TABLE 2 OXIDATIVE STABILITY (Formulation: 35 parts polymer, 65 parts Foral 105, 0.2 arts 'Ir anox' 1010.

Examples 11 - 13 and Comparative Example C4 Exampleε 11 - 13 and C4 illustrate the compatibility of E/nBA/CO compared with E/nBA with a range of varied tackifiers. In aεsesεing utility of a tackifier, the final compoεition must be both compatible, and flexible rather than brittle. Resultε of the test, shown in Table 3 εhow that at 25 and 26 wt% nBA for two terpolymerε and the copolymer, whether the CO level iε low (4%) or higher (9%) , the terpolymer blends show substantially greater compatibility. When the terpolymer composition was changed further, as in example 13, there are also a greater number of compositionε which εhow compatibility aε compared to Ex. C4. Uεeful compatibility with a larger range of tackifierε leads to composition versatility. Opaquenesε is a sign of incompatibility.

TABLE 3 COMPATIBILITY WITH VARIOUS TACKIFIERS

O = Opaque

Roεin Acid manufactured by Herculeε Inc. Roεin Ester manufactured by Hercules Inc. Roεin Eεter manufactured by Hercules Inc. terpene phenolic resin manufactured by Reichhold Che pure monomer aromatic resin mfg. by Hercules Inc.

hydrocarbon reεin manufactured by Herculeε (7) An aromatic hydrocarbon manufactured by Neville Chem.

(8) A terpene phenolic reεin manufactured by Reichhold Che

(9) A εynthetic polyterpene manufactured by Goodyear Tire and Rubber Co.

(10) A Roεin Eεter manufactured by Arizona Chem.

(11) A polymerized a-pinene manufactured by Herculeε Inc.

(12) A modified Roεin.ester manufactured by Hercules.

Examples 14 - 25 and Comparative Examples C5 - CIO. Examples 14 - 25 and C5 - CIO εhow that variouε terpolymerε formulated with different tackifier types, give adhesion to a whole range of varied substrateε that iε generally superior to ethylene vinyl acetate or ethylene butyl acrylate resin formulations. Despite the polar nature of the terpolymer, adhesion even to a non-polar resin like polyethylene iε still remarkably good. Ethylene vinyl acetate carbon monoxide terpolymer gives good adheεion, but aε εeen earlier, iε thermally unεtable. Reεultε are shown in Table 4. While the viscoεity of the formulationε waε not meaεured in moεt caεeε, all formulations were fluid at the application temperature.

TABLE 4 Adhesion of Terpolymer formulationε to Variouε Substrates

Adhesion to: Al(l) HDPE(2) PC(3) AC(4) PS(5) PVC(6) ABS(7) (Values in Psi.)

Ex # 14.

E/nBA/CO,MI=25 8

(66/25/9) ,+65%Tl NT 88 134 134 134 134 105

Ex.# 15.

Same +65%T2 NT 95 134 134 134 134 111 Ex.# 16.

E/nBA/CO,MI=90

(71/25/4) ,+65%Tl NT 50 134 134 134 134 107

Ex.# 17.

Same +65%T2 NT 58 134 119 134 134 102 Ex.# 18

E/nBA/CO,MI=6 (59/31/10) ,+65%Tl NT 97 134 134 134 134 106

Ex.# 19

E/nBA/CO,MI=150

(69/19/12) ,+65%Tl NT 50 75 80 80 83 55 EX.# 20

Same +65%T2 NT 20 80 80 50 80 72

Ex.# C5

E/VAc,MI=6

(72/28) +65%T1 NT 0 2 4 5 3 7 Ex.# C6

Same +65%T2 NT 38 32 46 98 27 73

Ex.# C7 E/VAc,MI=25 (54/28) +65%T1 NT 0 4 6 7 6 7

Ex.# C8

Same +65%T2 NT 63 30 68 103 80 63

Ex.# C9

E/nBA,MI=6

(74/26) NT 0 4 1 2 1 1

Ex.# 21 E/nBA/CO,MI= 6

(59/31/10)+60%Tl 333 63 104 NT 58 118 NT TABLE 4 (Continued) Adhesion of Terpolymer formulations to Various Substrat

Adheεion to: Al(l) HDPE(2) PC(3) AC(4) PS (5) PVC(6) ABS (Valueε in Psi. )

Ex.# 22

E/iBA/CO,MI=NM

(54/37.4/8.6)

+60%T1 111 43 92 NT 46 97 N

Ex.# 23 E/MA/CO,MI=NM (63.7/26.3/10) +60%T1 13 17 NT 35 35 N

Ex.# 24

E/EA/CO,MI=NM

(51.6/31.9/16.5)

+60%T1 99 12 46 NT 29 65 N

Ex.# 25

E/nBA/S02,MI=NM

(61.4/29.3/9.3)

+60%T1 148 13 44 NT 59 109

Ex.# CIO

E/VAc/C0,MI=NM

(56/34/10)

+60%T1 58 13 30 NT 33 53

NM Not Measured

NT Not Tested.

Tl = Foral 105, T2 = Kristolex 3070.

1. Aluminum

2. High Denεity Polyethylene.

3. 'Lexan' Polycarbonate reεin.

4. 'Lucite Acrylic resin.

5. Polystyrene reεin.

6. Rigid Polyvinyl chloride resin.

7. Acrylonitrile Butadiene Styrene reεin.

8. Value of 134 waε the maximum reading obtainable.

As many widely different embodiments of thiε invention may be made without departing from the εpirit and εcope thereof, it iε to be underεtood that this invention iε not limited to the εpecific embodiments thereof except aε defined in the appended claimε.

Claims

CLAIMS I claim,

1. A hot melt adhesive compoεition which is a molten fluid at application temperatures, consiεting essentially of an ethylene terpolymer containing about 40 to 87 wt. % ethylene, about 10 to 50 wt.% of a second monomer selected from the group consisting of alkyl acrylate and alkyl vinyl ether, wherein the alkyl contains 1 to 8 carbon atoms, and about 3 to 30 wt% of a third monomer selected from the group consisting of carbon monoxide and sulfur dioxide, based on the weight of the terpolymer, and about 5 to 80 wt% of a compatible tackifier based on the weight of the terpolymer plus tackifier.

2. The composition of claim 1 wherein the viscosity of the molten fluid at 177*C is no greater than about 50,000 cps.

3. The composition of claim 1 wherein the second monomer is present at a level of 15 to 40 wt. % and the third monomer is carbon monoxide.

4. The composition of claim 3 wherein the tackifier is present at a level of from 30 to 70 wt. %.

5. The composition of claim 1 containing compatible plasticizer.

6. The composition of claim 1 containing compatible wax.

7. The composition of claim 1 containing an effective amount of antioxidant.

8. A process of applying the adhesive composition of claim 1 at elevated temperatures, so as to transform the composition to a molten fluid, to any adherend of the group consisting of metals, wood, paper, cardboard, and polar and non-polar plastic materials, and while said composition is in molten fluid state, contacting the applied composition with a second adherend, and cooling the resultant composite structure..

9. The procesε of claim 8 wherein said plastic materials are selected from the group consisting of polyethylene, polyester, polyacrylate, polystyrene, polyvinylchloride and acrylonitrile butadiene styrene copolymers.