AU610959B2 - Epoxy resin compositions for use in low temperature curing applications - Google Patents

Description

tiignature(s) of declarant(s) To: The Commissioner of Patents THE DOW CHEMICAL COM NY RICHARD G. WATERMAN General Patent Counsel Agent: Phillips, Ormonde Fitzpatrick Note No egalization or other witness "eq. red.

2. 1.1

PCT

OPI DATE 01/06/89 AOJP DATE 06/07/89 APPLN. ID 27150 88 PCT NUMBER PCT/US88/03725 INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (51) International Patent Classification 4 )Inmnati a Publication Number: WO 89/ 04335 C08G 63/00 a•g Pu ati C08G 63/00 Q 1 at P at ate: 18 May 1989 (18.05.89) (21) International Application Number: PCT/US88/03725 (81) Designated States: AU, BR, DK, FI, JP, NO.

(22) International Filing Date: 21 October 1988 (21.10.88) Published With international search report.

(31) Priority Application Number: 116,593 Before the expiration of the time limit for amending the claims and to be republished in the event of the receipt (32) Priority Date: 3 November 1987 (03.11.87) of amendments.

(33) Priority Country: US (71) Applicant: THE DOW CHEMICAL COMPANY [US/ US]; 2030 Dow Center, Abbott Road, Midland, MI 48640 (US).

(72) Inventors: WYKOWSKI, Paul, L. 61 Blue Bell Court, Lake Jackson, TX 77566 PUCKETT, Paul, M.

126 Daisy, Lake Jackson, TX 77566 (US).

(74) Agent: FIFIELD, David, The Dow Chemical Company, P.O. Box 1967, Midland, MI 48641-1967 (US).

(54) Title: EPOXY RESIN COMPOSITIONS FOR USE IN LOW TEMPERATURE CURING APPLICATIONS (57) Abstract Compositions comprising a mixture of an epoxy resin composition consisting essentially of at least one epoxy resin which has an average of not more than 2 vicinal epoxy groups per molecule; at least one epoxy resin which has an average of more than 2 vicinal epoxy groups per molecule and at least one rubber or elastomer; and optionally, a low viscosity reactive diluent, are useful in preparing low temperature curable compositions. Also claimed is low temperature curable compositions containing the above components and at least one cycloaliphatic amine hardener and optionally, an accelerator for component

I_

I WO 89/04335 PCT/US88/03725 -1- EPOXY RESIN COMPOSITIONS FOR USE IN LOW TEMPERATURE CURING APPLICATIONS The present invention pertains to resinous compositions suitable for use in low temperature curing applications including the repair of composite articles.

Composites have been employed in the construction of all types of useful articles such as, storage vessels, transportation containers, vehicle parts including cars, trucks, boats and airplanes and the like. These objects, as with all objects, are subject to damage through use. In many instances, these damages will occur at places remote from adequate repair facilities and it is desirable to have means for expedient and often temporary but structurally sound repairs. One method for repairing these composite

I

WO 89/04335 PCT/US88/03725 wo 89/04335 PCT/US88/03725 -2articles is to adhere, via adhesive bonding, precured composite or metal repair patches to the damaged area(s). Another method is to remove the damaged part and rebuild the part under heat and vacuum in the same manner as. the original part was manufactured.

Since these composite objects are employed, for the most part outdoors, they are subjected to all types of environments. In humid environments, the composites tend to absorb moisture. The moisture in wet composites tends to vaporize when subjected to the heat usually involved in curing the patches during their repair, and causes blistering, disbondment and often delamination. It would be desirable to have available an adhesive and or a resinous binder material for use in the repair of the objects prepared from composites which cure below the normal curing temperature of the epoxy resins currently employed in the repair of composite parts or objects. The repair material would most preferably cure below the boiling point of water and produce a polymeric system which has thermal and mechanical properties similar to the composite part being repaired. One method to accomplish this is to have available such adhesive or binder resins which are low temperature curable but yet have sufficient thermal properties, cured strength and water resistance so as to be suitable for use in the repair of the damaged composites.

Low temperature curable epoxy resin systems with good thermal and mechanical properties would also find use in many other applications. Other applications for these resin systems would include uses such as electronic encapsulants, production of electrical laminates, and structural composite parts.

No~. WO 89/04335 PCT/US88/03725 -3- The ability to cure epoxy resins at relatively low temperatures would make these materials especially valuable in several composite production techniques like resin transfer molding, braiding, filament winding, pultrusion and similar methods of rapid composite formation.

florcY'"q 4 ±yke- pces e.r* rf enVr-i iPoue-s -Gine aspoet'&-^-e-p-r-3ef-i-e a composition which comprises an epoxy resin composition containing a mixture of at least one diglycidyl ether of a compound having 2 aromatic hydroxyl groups per molecule, said diglycidyl ether having an average of not more than 2 vicinal epoxy groups per molecule and an EEW of from 170 to 600; at least one polyglycidyl ether of a compound having an average of more than two aromatic hydroxyl groups per molecule, said polyglycidyl ether having an EEW of from 150 to 350; and a rubber or elastomer; wherein components and are present in amounts such that from 20 to 90 percent of the glycidyl ether groups are derived from component and from 10 to 80 percent of the glycidyl ether groups are derived from component and component is present in an amount of from 2 to 20 percent by weight based on the combined weight of components and and optionally, as a reactive diluent to lower the viscosity of the composition, a low viscosity WO 89/04335 PCT/US88/03725 -4monoglycidyl ether compound or a low viscosity polyglycidyl ether of a compound having two or more aliphatic hydroxyl groups per molecule; and wherein component is present in an amount of from zero to 25 percent by weight based on the combined weight of components and 7r o -Portiher e -roc- i ro snc OF A4ther--a-speGt- the present invention |-klce .s pertai4s-tea low temperature curable composition which comprises an epoxy resin composition containing a mixture of at least one diglycidyl ether of a compound having 2 aromatic hydroxyl groups per molecule, said diglycidyl ether having an average of not more than 2 vicinal epoxy groups per molecule and an EEW of from 170 to 600; at least one polyglycidyl ether of a compound having an average of more than two aromatic hydroxyl groups per molecule, said polyglycidyl ether having an EEW of from 150 to 350; and a rubber or elastomer; wherein components and are present in amounts such that from 20 to 90 percent of the glycidyl ether groups are derived from component and from 10 to 80 percent of the glycidyl ether groups are derived from component and component is present in an amount of from 2 to 20 percent by weight based on the combined weight of components and 01. i I Mw w WO 89/04335 PCT/US88/03725 optionally, as a reactive diluent to lower the viscosity of the composition, a low viscosity monoglycidyl ether compound or a low viscosity polyglycidyl ether of a compound having two or more aliphatic hydroxyl groups per molecule; at least one cycloaliphatic amine hardener; optionally, an accelerator for component and wherein component is employed in an amount of from 1 0 about zero to 25 percent by weight based upon the combined weight of components and component is employed in an amount which provides a ratio of equivalents of component per epoxide equivalent of components and combined of from 0.95:1 to 1.2:1; and component is employed in an amount of from zero to 5 percent by weight based upon the combined weight of components and A +ster f5-e-t- -h-e--p--s-ent in en- n °l-hereC i°c e a laminate or composite article resulting from curing a composition comprising the aforementioned curable composition and at least one reinforcing material.

The present invention provides adhesive or binder resin compositions which are low temperature curable and have sufficient cured strength and water resistance so as to be suitable for use in the repair of damaged composites.

DETAILED DESCRIPTION OF THE INVENTION Suitable diglycidyl ethers having an average of not more than two vicinal epoxy groups per molecule include, for example, those represented by the" formulas I, II and III following formulas I, II and III t, ii i.

.1: FORMULA I 0 11 2 C -C-OH 2

R

0

(X)

4

OH

O-C11 2

-C-CH

2 0

R

(X)

4 0 O0- CH 2 -C CH 2

R

FORMULA II 0 H2C- C-CH 2 -0

R

(X)4 la(AK

(X)

4

MX

4 0(A)n e 4 0

CH

2 -C -CH 2

R

WO 89/04335 PCT/US88/03725 -7- FORMULA m 0 0 H2C--C-CH2-0

O-CH

2 -C CH2 (X)4 n R 10 1 wherein A is a divalent hydrocarbyl group having suitably from 1 to 12, more suitably from 1 to 6, most suitably from 1 to 3, carbon atoms, SO-, -S02-, -CO- or each R is independently hydrogen or an alkyl group having from 1 to 4 carbon atoms; each X is independently hydrogen, a hydrocarbyl group or substituted hydrocarbyl group having suitably from 1 to 10, more suitably from 1 to 6, most suitably from 1 to 3, carbon atoms, a halogen atom, particularly chlorine or bromine, or a nitro group; n has a value of zero or 1; n' has an average valec suitably from zero to 3, more suitably from zero to i.5, most suitably from zero to 0.5; and n" has an average value suitably from 1 to 12, more suitably from 1 to 6, most suitably 2 from 1 to 3.

The term hydrocarbyl as employed herein means any aliphatic, cycloaliphatic, aromatic, aryl substituted aliphatic or cycloaliphatic, or aliphatic or cycloaliphatic substituted aromatic groups. The term substituted means that the hydrocarbyl group can be substituted with halogen atoms, particularly chlorine or bromine, or nitro groups.

Particularly suitable diglycidyl ethers of compounds having two aromatic hydroxyl groups per molecule which can be employed herein include those diglycidyl ethers of bisphenols such as bisphenol A, bisphenol F, bisphenol K, bisphenol S, dihydroxybiphenyl, as well as the halogenated and alkyl derivatives thereof such as chlorine, bromine and alkyl derivatives having from 1 to 4 carbon atoms. These diglycidyl ethers having an average of not more than two glycidyl ether groups per molecule suitably have an epoxide equivalent weight (EEW) of from 170 to 600, more suitably from 170 to 360, most suitably from 170 to 250.

Suitable epoxy resins having an average of more than two vicinal epoxy groups per molecule include, for example, those represented by the following formulas IV, V and VI i' I; i

K--

FORMULA IV 0 O CH 2 -C-CH2 I I O -CH 2 -C-CH2 I I 0 O CH 2 -C-CH2

R

(X)

3

(X)

4 FORMULA V 0 -CH2 0 Q-CH2-C -CH2 I I 4 FORMULA VI 0

H

2 C- CH 2

-C-

R

(X)4 R 0

(X)

4 OH (X) 4 R (X)4 CH2-C CH2-O

R

(X)4 0

CH

2 -C CH2 MISi R CH2

-C-R

C H2 CH2 CH2 compound having an average of more than two aromatic hydroxyl groups per molecule, said polyglycidyl ether having an EEW of from 150 to 350; and wherein each R, X and n" are as defined above, each A' is independently a divalent hydrocarbyl or substituted hydrocarbyl group having suitably from 1 to 12, more suitably from 1 to 6, most suitably from 1 to 3, carbon atoms; R' is hydrogen or a monovalent hydrocarbyl group or substituted monovalent hydrocarbyl group having suitably from 1 to 4, more suitably from 1 to 3, most suitably from 1 to 2, carbon atoms; m has a value suitably from 0.01 to 12, more suitably from 1 to 6, most suitably from 1 to 3; m' has a value suitably from 1.01 to 12, more suitably from 2 to 6, most suitably from 2 to 3; m" has an average value suitably from zero zero to 2.

Particularly suitable polyglycidyl ethers of a novolac resin (formula IV) which can be employed herein include those polyglycidyl ethers of novolae resins prepared by reacting an aldehyde with phenol or substituted phenol. Particularly suitable aldehydes include, for example, formaldehyde, acetaldehyde, butyraldehyde, salicylaldehyde, benzaldehyde and combinations thereof. Particularly suitable phenols include, for example, phenol, cresol, bromophenol, chlorophenol, and combinations thereof. The polyglycidyl ethers of a novolac resin employed herein have an EEW of from 150 to 220, more suitably from 170 to 190.

I~ WO 89/04335 PCT/US88/03725 -13- Particularly suitable polyglycidyl ethers of an adduct of an ethylenically unsaturated hydrocarbon and a compound containing an aromatic hydroxyl group (formula V) include, for example, adducts of dicyclopentadiene or higher oligomers of cyclopentadiene and phenol, cresol, chlorophenol or bromophenol. These polyglycidyl ethers have an EEW of from 150 to 350, more suitably from 200 to 300.

The epoxy resins are employed in quantities such that suitably from 20 to 90, more suitably from to 90, most suitably from 60 to 80, percent of the glycidyl ether groups are contributed by component (A- 1) and suitably from 10 to 80, more suitably from 10 to 50, most suitably from 20 to 40 percent of the glycidyl ether groups are contributed by component Suitable cycloaliphatic amine hardeners or curing agents which can be employed herein include, for example, those represented by the following formulas VII and VIII FORMULA VII NH2-(A)n S (A)n-NH2 (X')4 i i WO 89/04335 PCT/US88/03725 -14- FORMULA VIII (X')4 NH2-(A)n S (A)n-NH2 Swherein each A and n is as defined above and each X' is independently hydrogen or an alkyl group having suitably from 1 to 12, more suitably from 1 to 6, most suitably from 1 to 3, carbon atoms.

S Particularly suitable such hardeners or curing agents include, for example, 1,2-diaminocyclohexane, 1,3diaminocyclohexane, 1,4-diaminocyclohexane, menthane diamine, isophoronediamine, 1,3-di(aminomethyl)cyclohexane, 4,4'-methylenedicyclohexylamine. 3,3'-dimethyl- -4,4'-diaminodicyclohexylmethane, and combinations thereof.

The cycloaliphatic amine hardener is employed in amounts which provide a ratio of equivalents of hardener (component C) to equivalents of epoxy equivalent contained in components and combined suitably from 0.95:1 to 1.2:1, more suitably from 0.95:1 to 1.15:1, most suitably from 1:1 to 1.15:1.

Suitable rubbers or elastomers employed in the epoxy resin compositions herein can include, for example, carboxyl-containing rubbers or elastomers, copolymers of alkyl acrylates or methacrylates or alkyl esters of other alpha-alkyl substituted ethylenically unsaturated acids, or grafted rubber particles WO 89/04335 PCT/US88/03725 characterized by having a rubbery core and a grafted polymer shell which is compatible with epoxy resins.

Particularly suitable rubbers or elastomers are the carboxyl-containing butadiene/acrylonitrile rubbers or elastomers. Other rubbers or elastomers which can be employed similarly include poly(butadiene/acrylonitrile) copolymers which contain terminal or pendant amine groups. These rubbers or elastomers containing secondary amine groups, or carboxyl-containing moieties are commercially available from the B. F. Goodrich Company under the tradename HYCAR.

Particularly suitable rubbers or elastomer; which can be similarly employed include polymers formed 1 by polymerizing monomers, such as alkyl acrylate and alkylmethacrylate, in situ in the epoxy resin in the presence of a stabilizer to form a stable dispersed polymer phase according to the methods disclosed by D.

2 K. Hoffman and C. Arends in U.S. Patent 4,708,996 and also by R. E. Adam et al. in U.S. Patent 4,524,181.

Another particularly suitable form of rubber or elastomer for modification of the epoxy resins of the present invention includes those available in the form of a rubber-modified epoxy composition comprising (1) an epoxy resin continuous phase and a stabilized discontinuous phase of grafted rubber particles, which particles have a resin-insoluble rubbery core with a shell which is compatible with the epoxy phase but has latent reactivity with a curing agent. These grafted rubber concentrates (GRC) can be prepared by the methods described by D. E. Henton, C. B. Arends, D. M.

Pickelman and V. E. Meyer in U.S. Patent 4,778,851.

Preferred grafted rubber compositions have, as the rubbery core components, conjugated dienes such as electrical laminates, and structural composite parts.

WO 89/04335 PCT/US88/03725 -16butadiene and isoprene, acrylate rubbers such as 2ethylhexyl acrylate and butyl acrylate rubber and interpolymers. Particularly preferred are cores of crosslinked butadiene rubber. Preferred compounds for the grafted shell are polymers of ethylenically unsaturated compounds such as styrenics, acrylates and methacrylates, acrylonitrile, acrylic and methacrylic acid, vinylized glycidyl ethers such as glycidyl acrylate and methacrylate and combinations thereof.

The shell compounds contain a functionality which reacts with functionalities of the epoxy resin continuous phase.

These rubber or elastomer modifiers can be employed in amounts suitably from 2 to 20, more suitably from 2 to 15, most suitably from 3 to percent by weight based upon the total weight of the glycidyl ether compounds and the rubber or elastomer modifiers.

Also, the compositions of the present invention can contain catalysts or accelerators (component for the curing thereof. Suitable such catalysts or accelerators include, for example, imidazoles, tertiary-amines, tertiary-phosphines, quaternary phosphonium salts, phenolics and combinations thereof.

Particularly suitable catalysts or accelerators include, for example, aminoethylpiperazine, 2methylimidazole, 2-ethyl-4--methylimidazole, 2phenylimidazole, 2-undecyl-imidazole, 2-heptadecylimidazole, 2-ethylimidazole, 2-isopropylimidazole, 2-phenyl-4-methylimidazole, dimethylaminomethyl phenol, tridimethylaminomethyl phenol, N,N-dimethylaniline, tetrabutylphosphonium V L 'D U WO 89/04335 PCT/US88/03725 -17acetate*acetic acid complex benzyldimethylamine, and combinations thereof.

The catalysts or accelerators are employed in quantities which provide suitably from zero to 5, more suitably from 0.05 to 2.5, most suitably from 0.5 to 2 percent by weight based upon the combined weight of components and Suitable monoglycidyl ether compounds which can be employed herein as reactive diluents (component include, for example, butyl glycidyl ether, phenyl glycidyl ether, epoxidized soybean oil, and combinations thereof. Also suitable as reactive diluents are the glycidyl ethers of polyhydroxyl compounds such as, for example, the polyglycidyl ethers of propylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, neopentylglycol, glycerol, trimethylol propane, copolymers of propylene oxide, 2 ethylene oxide, butylene oxide or mixtures of such oxides, glycerol or trimethylol propane initiated polymers of propylene oxide, ethylene oxide, butylene oxide or a mixture of such oxides, the glycidyl ethers of thiodiglycol, dithiodiglycol, thioether polyols, and combinations thereof.

The reactive diluents are employed in amounts suitably from zero to 25, more suitably from 2 to Smost suitably from 5 to 15, percent by weight based upon the combined weight of components and The compositions of the present invention can also, if desired, contain reinforcing materials in the Sform of mats, woven fabric, unidirectional fibers, ovings, random fibers or filaments, inorganic fillers, rovings, random fibers or filaments, inorganic fillers, (i M r- I jA A >t -4- WO 89/04335 PCT/US88/03725 -18inorganic whiskers, hollow spheres, ceramics, and the like. These reinforcing materials can be prepared from glass fibers, aramid fibers, graphite fibers, and polymer fibers such as nylon, polyalkylene terephthalate, polyethylene, polypropylene, polyesters, and combinations thereof.

If desired, other components can be included in the compositions of the present invention, for.example, pigments, dyes, fillers, wetting agents, stabilizers, mold release agents, flow control agents, fire retardant agents, surfactants, and combinations thereof. These components are included in amounts which are effective for their purpose, e.g. pigments and dyes are employed in amounts sufficient to color the composition to the extent desired and wetting agents are employed in amounts sufficient to wet out any reinforcing materials present in the compositions.

These additives are added in functionally equivalent amounts e.g. the pigments and/or dyes are added in quantities which will provide the composition with the desired color; however, they are suitably employed in amounts of from zero to 20, more suitably from 0.05 to 5, most suitably from 0.5 to 3 percent by weight based upon the weight of total blended composition.

Fillers are employed in amounts which will provide the composition with the desired consistency; however, they are suitably employed in amounts of from zero to 95, more suitably from 10 to 80, most suitably from 40 to 60 percent by weight based upon the weight of total composition.

IOLUWL[1 £UL IIIL LCL,) -L .4 4 i-1; oA WO 89/04335 PCT/US88/03725 -19- The present invention will further be described with reference to the following examples.

The following epoxy resins are employed in the examples.

Epoxy Resin A is a diglycidyl ether of bisphenol A having an epoxide equivalent weight (EEW) of 176.

Epoxy Resin B is a hydrocarbon epoxy novolac resin prepared from dicyclopentadiene and phenol having an EEW of 253 and an average functionality of 3.2.

Epoxy Resin C is a phenol-formaldehyde epoxy novolac resin having an EEW of 181 and an average functionality of 3.6.

Rubber Modifier A is a copolymer rubber of 2ethylhexylacrylate dispersed in the epoxy resin mixture.

Catalyst or Accelerator A is 2-ethyl-4methylimidazole added in an amount based on the total weight of the epoxy resin blend and curing agent.

EXAMPLES

A sample of the epoxy resin(s) was warmed to if necessary, to make it pourable. The sample was weighed 0.01 g) by pouring into a glass container.

When a mixture of epoxy resins was employed, the glass container, after sealing, was placed in a shaker bath under gentle heating until a homogeneous solution was obtained. Approximately 0.4 g 0.1 mg) of the resultPnt solution was weighed into a glass container and dissolved in 15 ml of methylene chloride. A 15 ml t WO 89/04335 PCT/US88/03725 aliquot of 1N tetraethylammonium bromide in acetic acid was added to the dissolved resin along with 4 drops of crystal violet indicator. The sample was then titrated to a green end point against standardized 0.1 N perchloric acid in glacial acetic acid. Based on the measured equivalent weight of the above resin or resin mixture, the resin or resin mixture was thoroughly mixed with a 10% stoichiometric excess of diaminocyclohexane as a hardener (curing agent).

A mixture of the epoxy resin, cycloaliphatic amine hardener, and catalyst was mixed together at a temperature between 25 0 C to 45 0 C. After thorough mixing the mixture was degassed by evacuating the mixture to a pressure of 1 torr (atmosphere). The resultant degassed mixture was then poured into each of two molds consisting of two 13 in. x 13 in. x 0.125 in. (330 mm x 330 mm x 3.175 mm) polished aluminum plates separated by 0.125 in. (3.175 mm) spacers and a silicone rubber gasket. The cast mixtures were allowed to cure at for 250 minutes after which one of the resultant cured, cast sheets was demolded. The second casting was further cured for 120 minutes at 177 0 C. After cooling, the cured resins were prepared for testing by the following methods: ASTM D-638 (tensile); ASTM D-790 (flexural) and ASTM D-648 (heat distortion temperature,

HDT).

Water absorption was determined from specimens of 1 in. x 3 in. (25.4 mm x 76.2 mm) coupons of the abovre mentioned castings. The edges of the coupons were sanded successively with 320, 400 and 600 grit emery cloth. The specimens were dried at 90 0 C overnight and cooled for 2 hours in a desiccator. The samples were weighed and then immersed in boiling water. The Eh'- 1- I I A I WO 89/04335 FACT/US88/03725 -21samples are removed, dried and weighed at intervals during the test. The final weighing was performed after 168 hours.

Barcol Hardness was determined from a Barber- Coleman Impressor model GTZJ 934-1 and was expressed as the average of 10 measurements.

The glass transition temperature (Tg) was 1 determined by thermomechanical analysis (TMA) on a DuPont instrument model 1090 series 4 thermal analysis instrument.

The viscosity of the resin or resin mixture was 1 determined by a Brookfield model DV-II cone and plate viscometer at 25°C with a no. 41 spindle. Viscosities of the resin or resin mixture with and without hardener (curing agent) was measured. After the four hour period, the castings were removed from the oven and glass transition temperatures are measured by differential scanning calorimetry (DSC) and thermomechanical analysis (TMA). The residual energy of curing was also measured by DSC.

The resins and resin mixtures and results of the experiments are given in Table I.

I

TABLE I Components Expt. Expt. Expt. Expt. Expt. Expt. Expt. Expt.

andA*B

*DEF

Properties A *C Resin A wt 100 100 70 70 65 65 65. Resin B wt 30 Resin C wt 30 30 30 30 Rubber wt 5 5 5 Resin mass, g 272.98 272.99 253.86 251.39 275.57 275.58 279.52 279.53 Hardener mass, g 418-79 418.79 116.17 415.73 116.23 416.23 412.25 112.26 Catalyst Mass, g 3.3 3.29 3.06 3.02 3.25 3.25 3.25 3.25 Viscosity of Mixture, cps 233 880-- 0

C

Curing Cond. 90/252 90/252 90/2541 90/2419 90/250 90/250 90/255 i0/255 C m i n1 7 3 Post-Cure 'Cond. 177/128 177/132 177/12917/3 Oc/min an example of the Fpre-sentIi-nvnT'n

I

L

0 ___TABLE I (Continued) Components Expt. Expt. Expt. Expt. Expt. Expt. Expt. Expt.

andA*B

*DEFGH

Properties A ~D Tensile kpsi 12.14 8 10.6 8.1 11.6 10.3 11.6 11 3 Strength mPa 85.5 ec 73.1 55.8 79.8 71 80 77.9 Tensile kpsi 4314 397 441 448 407 382 415 3814 Modulus GPa 2.99 2.714 3.041 3.09 2.81 2.63 2.86 2.65 Elongation 6.6 2.6 3.7 2.3 5.0 41.7 5.8 6.3 Flexural kpsi 22.6 18.7 22.2 20.6 20.6 18.8 19.9 19.7 Strength kPa 155.8 128.9 153.1 1412 1412 129.6 137.2 135.8 Flexural kpsi 4160 1441 509 467 458 423 462 413 Modulus GPa 3.1 3.014 3.51 3.22 3.16 2.92 3.19 2.8 Barcol Hardness 39 38 412 144 25 29 23 Water 3.227 3.062 3.2 3.1841 3.14144 3.060 3.044 2.5142 Absorption Heat Distortion Temp. (2614 psi 1214 132 118 1110 118 1111 119 1145 Load), 'CIIIIII Tg by TMA 1041-11-0 1 143-151 1108-1091 1111-1412 1103-101 165-171 1120-126 1 57-161 *Not an example oftthe present invention.

Claims (6)

1. A composition which comprises an epoxy resin composition containing a mixture of at least one diglycidyl ether of a compound having 2 aromatic hydroxyl groups per molecule, said diglycidyl ether having an average of not more than 2 vicinal epoxy groups per molecule and an EEW of from 170 to 600; at least one polyglycidyl ether of a compound having an average of more than two aromatic hydroxyl groups per molecule, said polyglycidyl ether having an EEW of from 150 to 350; and a rubber or elastomer; wherein components and are employed in amounts such that from 20 to 90 percent of the glycidyl ether groups are derived from component and from 10 to 80 percent of the glycidyl ether groups are derived from component and component is employed in an amount of from 2 to 20 percent by weight based on the combined weight of components and WO 89/04335 PCT/US88/03725 o-ccoacLa +0

2. A composition pi Claim 1 which further comprises as a reactive diluent to lower the viscosity of the composition, a low viscosity monoglycidyl ether compound or a low viscosity polyglycidyl ether of a compound having two or more aliphatic hydroxyl groups per molecule in an amount of up to 25 percent by weight based on the combined weight of components and

3. A composition of Claim 1 or 2 wherein component is an epoxy resin or mixture of epoxy resins represented by the following formulas I, II or III 23 1 *o i i ~i -r FORMULAI 0 H 2 C -C-CIH2 R 0 (X) 4 OH 4 0 0 0-CH 2 -C -CR 2 R ni FORMULA II H 2 C- C-CH2-O R (X) 4 l(A)n- (X) 4 (X) 4 -0 @A)n

7- 0- 0 0 CH 2 -C -CH2 WO 89/04335 PCT/US88/03725 -27- FORMULAIII H2C- C-CH2-O R R (X)4 0 0-CH 2 -C CH 2 JI (X) 4 wherein A is a divalent hydrocarbyl group having from 1 to 12 carbon atoms, -S02-, -CO- or each R is independently hydrogen or an alkyl group having from 1 to 4 carbon atoms; each X is independently hydrogen, a hydrocarbyl group or substituted hydrocarbyl group having from 1 to carbon atoms, a halogen atom, or a nitro group; n has a value of zero or 1; and n' has an average value from zero to 3; n" has an average value from 1 to 12; component is an epoxy resin or mixture of epoxy resins represented by the following formulas IV, V or VI I -e J. L4IJL~.~ WO 89/04335 PCT/US88/037 2 -28- C N 0- 0- 0 I- 0- C N 0- Z- 0 00 FORMULA V 0 O-CH 2 -C -CH2 I I 0 O-CH 2 -C -CH2 I I Wx) 4 nil 3 WO 89/04335 PCT/US88/037 2 0 <I_ C-, E go 0 C-, 0 I: 0 I-1 I C., cKJ 0 1Z4 "I WO 89/04335 PCT/US88/03725 -31- wherein each R, X and n" are as previously defined; each A' is independently a divalent hydrocarbyl or substituted hydrocarbyl group having from 1 to 12 carbon atoms; R' is hydrogen or a monovalent hydrocarbyl group or substituted monovalent hydrocarbyl group having from 1 to 4 carbon atoms; m has a value from 0.01 to 12; m' has a value from 1.01 to 12; and m" has a value from zero to 4. A composition of Claim 3 wherein component is a diglycidyl ether of bisphenol A; component is a phenol-formaldehyde or a cresol-formaldehyde epoxy novolac resin or a polyglycidyl ether of an adduct of dicyclopentadiene and phenol or cresol; and 2 the rubber or elastomer, component is poly(2-ethylhexylacrylate) copolymer rubber, grafted rubber particles or combinations thereof. 25 5. A low temperature curable composition a-ccoc r-ck 1%o which comprises a composition -of Claim 1 or Claim 2 and at least one cycloaliphatic amine hardener; wherein component is employed in an amount which provides a ratio of equivalents of component per epoxide equivalent of components and combined of from 0.95:1 to 1.2:1. cc-cor-cn- L \0 6. A low temperature curable composition SClaim 5 which further comprises an accelerator for component in an amount of up to 5 percent by weight -32- based upon the combined weight of components and 7. A low temperature curable composition according to claim 5 or claim 6 wherein component is a curing agent or mixture of curing agents represented by the following formulas VII or VIII FORMULA VII NH2-(A)n (A)n-NH2 a a' p p I* (X')4 FORMULA VIII (X')4 )4 NH2-(A)n (A)n (A)n-NH2 wherein each A and n is as defined above and each X' is independently hydrogen or an alkyl group having from 1 to 12 S. carbon atoms.

8. An article resulting from curing the composition according to any one of claims 5 to 7 which contains a reinforcing agent.

9. A composition according to claim 1 substantially as hereinbefore described with reference to any one of the examples. D 'a INTERNATIONAL SEARCH REPORT International Application No. PCT/US88 03725 I. CLASSIFICATION OF SUBJECT MATTER (if several classification symbols apply, indicate all) 6 According to International Patent Classification (IPC) or to both National Classification and IPC 6TP CLC9 0 8 A 0 2 113, 122 II. FIELDS SEARCHED Minimum Documentation Searched 7 Classification System Classification Symbols US. CL. 525/65, 113, 122 523/428, 434 428/272, 273, 290 Documentation Searched other than Minimum Documentation to the Extent that such Documents are Included in the Fields Searched 8 III. DOCUMENTS CONSIDERED TO BE RELEVANT 9 Category Citation of Document, it with indication, where appropriate, of the relevant passages 12 Relevant to Claim No. 3 A US, A, 3,496,250 (CZERWINSKI) 17 FEBRUARY 1970 A US, A, 3,855,176 (SKIDMORE)17 DECEMBER 1974 A US, A, 3,894,113 (PAGEL) 08 JULY 1975 A US, A, 3,926,904 (SCOLA) 16 DECEMBER 1975 A US, A, 4,082,895 (BACKDERF)04 APRIL 1978 A US, A, 4,500,660 (MINAMISAWA) 19 FEBRUARY 1985 A US, A, 4,524,181 (ADAM) 18 JUNE 1985 A US, A, 4,680,076 (BARD) 14 JULY 1987 Special categories of cited documents: 1 t later document published after the international filing date document defining the general state of the art Which is not or priority date and not in conflict with the apolication but A considered to b rse of te arthch relevance cited to understand the principle or theory underlying the considered to be of particular relevance invention earlier document but published on or after the international document of particular relevance: the claimed invention filing date cannot be considered novel or cannot he considered to document which may throw doubts on priority claim(s) or involve an inventive step which is cited to establish the publication date of another document of particular relevance; the claimed invention citation or other special reason (as specified) cannot be considered to involve an inventive step when the document referring to an oral disclosure, use, exhibition or document is combined with one or more other such docu- other means ments, such combination being obvious to a person skilled document published prior to the international filing date but in the art. later than the priority date claimed document member of the same patent family IV. CERTIFICATION Date of the Actual Completion of the International Search Date of Mallinj t ts Iterntl nal Search Report 24 JANUARY 1989 International Searching Authority Signature of Authored ar ISA/US EARL A. NIELSEN Form PCT/ISA/210 (econd sheet) (Rev.11-87)