Abstract: Disclosed is a curable composition comprising (A) an imidazole derivative represented by the following general formula (1), which is capable of generating free imidazole by exposure to light, and (B) a polyfunctional epoxy compound: ##STR1## wherein R represents a hydrogen atom, a halogen atom, an alkyl group, an aryl group, an aralkyl group, a nitro group, a cyano group, an alkoxyl group, a phenoxy group, or an aromatic ring residue capable of forming a condensed ring in combination with a benzene ring. The composition may further incorporate therein at least one compound selected from the group consisting of polyfunctional phenol compounds, polyfunctional carboxylic acids, acid anhydrides, and amine compounds.

Abstract: A newly-blended one part system heat-resistant epoxy resin composition which exhibits excellent stability at room temperature, quickly undergoes the curing reaction, molded within short periods of time, and, after cured, exhibits excellent Tg, resistance against the water, resistance against degradation by heat, and a variety of excellent properties in combination. The heat-resistant epoxy resin composition having excellent stability at room temperature comprises an epoxy compound having two or more epoxy groups, a curing agent which comprises a naphthalenedicarboxylic dihydrazide as a main component, and a ceramic whisker as a filler.

Abstract: Curing components containing amino groups for curing epoxy resins are obtained by the reaction of alkylated polyhydroxy aromatics (A) with polyamines (B) and aldehydes (C) by the mechanism of the Mannich reaction. The preparation of curable mixtures and varnish formulations is also disclosed. The curing components and curable mixtures can also be employed at a low temperature.

Abstract: Curing components containing amino groups for curing epoxy resins are obtained by the reaction of alkylated polyhydroxy aromatics (A) with polyamines (B) and aldehydes (C) by the mechanism of the Mannich reaction. The preparation of curable mixtures and varnish formulations is also disclosed. The curing components and curable mixtures can also be employed at a low temperature.

Abstract: Curable mixtures comprising(a) an epoxy compound having on average more than one epoxy group per molecule,(b) a metal complex salt of formula IM(L).sub.a X'.sub.b X".sub.c .cndot.dY (I),whereinM is a cation of a transition metal,L is a Lewis base,a is a number from 2 to 6,X' is an anion of an acid radical,X" is an cation of an acid radical differing from X'b is 0 or a number which, together with the number c, which is greater than 0, corresponds to the valency of the cation of the transition metal,Y is a solvent molecule, andd is 0 or a number from 0 to 5, and,as optional component(c) a hardener for epoxy resins,are distinguished by good solubility of the metal salt in the epoxy resin and achieve uniform crosslinking during the curing of the epoxy resin.

Abstract: A curing agent for epoxy resins is prepared from an amine and an epoxy, as well as subsequent modification by a polyisocyanate compound, in such a manner that the curing agent is in the form of small spherical particles. The particles can be as small as 0.1 microns. This curing agent can be easily dispersed in curing agent masterbatches and curable compositions with minimal effect on their storage stability. The resulting curable compositions have a wide range of applications, including automobile and electronic adhesives.

Abstract: N-Alkyl-N'-aryl-p-phenylenediamines, when added at 2.5 to 12.5% by weight, based on the total weight of the epoxy resin and hardener, cause the epoxy resin after curing to exhibit substantial increases in physical properties, such as strength, stiffness, toughness and hot/wet properties, compared to the properties of the cured, but unmodified epoxy resin.

Abstract: An epoxy resin composition comprising an epoxy resin component containing at least 5% by weight of an epoxy resin of Formula [I], an epoxy hardener, and an inorganic filler as essential constituents: ##STR1## [wherein R and R.sup.1 denote alkyl of C.sub.2 to C.sub.6, and n is an integer repetition unit from 0 to 10.]. The epoxy resin composition, when used as a molding material, is low in water absorption rate and flexural modulus (low stress).

Abstract: The present invention provides polyhydric phenols which are starting materials for glycidyl ether compounds which can provide cured products having low moisture absorption, high heat resistance and improved crack resistance and can be used for encapsulating semiconductor devices. The polyhydric phenols are represented by the following formula: ##STR1## wherein R.sup.1 independently represents a halogen atom, an alkyl or cycloalkyl group of 1-9 carbon atoms, an alkoxy group of 4 or less carbon atoms or an aryl group and R.sup.1 may be identical or different when l is 2 or more, R.sup.2 independently represents a halogen atom, an alkoxy group of 4 or less carbon atoms or an alkyl group of 6 or less carbon atoms and R.sup.2 may be identical or different when m is 2 or more, R.sup.

Abstract: A curable resin comprising a mixture of (a) a component consisting of at least one thermically curable compound containing at least one 1-oxa-3-aza tetraline group, and (b) a component consisting of at least one curable brominated epoxy resin.

Abstract: An acid anhydride-containing one package epoxy resin composition consisting indispensably of (1) an epoxy resin having two or more epoxy groups in one molecule, (2) an acid anhydride, (3) at least one of (a) a liquid latent curing accelerator, (b) a latent curing accelerator soluble in an epoxy resin having two or more epoxy groups in one molecule and (c) a latent curing accelerator soluble in an acid anhydride, and (4) a dispersible latent curing accelerator, wherein the ratio of (1) to (2) is from 0.8 to 1.2, defined as the number of acid anhydride equivalents/the number of epoxy equivalents, and the amounts of (3) and (4) each are from 0.1 to 10 parts by weight to 100 parts by weight of the epoxy resin. The composition has excellent infiltrability, storage stability and reactivity.

Abstract: The present invention relates to a modified epoxy resin, a method for the preparation thereof and an epoxy resin composition using the modified epoxy resin. In particular, it relates to a modified epoxy resin of the general formula (I) which is prepared by incorporating a monomaleimide having a carboxy group useful as a heat resistance-improving agent of a resin composition containing an epoxy resin and maleimides into an epoxy resin, and an epoxy resin composition for sealing a semiconductor element having the improved heat resistance and moldability by the modified epoxy resin. ##STR1## wherein, R represents a hydrogen atom or an alkyl group having from 1 to 10 carbon atoms (C.sub.1 to C.sub.10), andn is 0 to 100, and m is 1 to 100.

Abstract: A polymerizable mixture comprising 100 parts by weight of at least one epoxy compound and 0.01 to 50 parts by weight of a metal complex compound of the formulaML.sub.x B.sub.y or M[SR].sub.x B.sub.z,wherein M is a metal ion of a metal of main groups II and III and sub-groups thereof of the Periodic Table, L is a chelate forming ligand selected from the group consisting of dioximes, .alpha.- and .beta.-hydroxycarbonyl compounds or enolizable 1,3-diketones, SR is an acid ion of an inorganic acid, B is a Lewis base, x is an integer from 1 to 8, y is an integer from 1 to 5 and z is an integer from 7 or 8 with the proviso that B is not a polyvalent phenolic compound and a process for the polymerization thereof.

Abstract: Compositions comprising epoxy resins containing one or more rodlike mesogenic moieties per molecule are cured with polyamines containing one or more rodlike mesogenic moieties per molecule. These curable compositions can be oriented by the application of an electric field or magnetic field or drawing and/or shear flow prior to and/or during curing. The resultant cured products exhibit an improvement in one or more physical and/or mechanical and/or thermal properties as compared to a like epoxy resin system which does not contain any rodlike mesogenic moieties.

Abstract: The invention relates to a resin transfer molding preform binder resin that comprises at least one aromatic polyepoxide, a fluorene epoxide that is different than the aromatic polyepoxide and having a defined structure, and a 9,9-bis(aminophenyl)fluorene curing agent. The binder resin is a solid, room temperature stable, essentially nonsintering powder that displays a glass transition temperature greater than about 40.degree. C. Also disclosed are preforms made with the binder resin and a method for preparing the preforms.

Abstract: A superior thermal transfer film adhesive comprises the following composition: (a) at least one aliphatic epoxy resin; (b) a stoichiometric amount of at least one aliphatic polyamine curative; (c) an effective amount of a thixotropic agent, such as fumed silica; and (d) about 20 to 50 volume percent of at least one filler, such as alumina, based on the total of the epoxy resin and the curative. The aliphatic epoxy resin has aliphatic pendant chains of 6 to 20 carbon atoms in length. The curative comprises a long chain aliphatic or cycloaliphatic curing agent for the epoxy resin. Since aliphatic moieties, which are flexible, are used, the glass transition temperature of the resulting cured material is lower than epoxies and plasticizers employing rigid moieties. The adhesive of the invention is novel in attaining high volume resistivity (at least 10.sup.14 ohm-cm at 25.degree. C.), low temperature flexibility (-55.degree. C.), excellent adhesion for maximum thermal transfer, and ease of reworkability.

Abstract: Glycidyl amines containing mesogenic moieties result in improved properties when cured. These amines are useful in coatings, adhesives, encapsulants, moldings, laminates, and the like.

Abstract: A thermosetting resin composition contains (A) a mixture of an imide compound having an allyl-free maleimide group and an imide compound having an allyl-containing imide group, (B) an epoxy resin, (C) a phenolic resin, and optionally, (D) an aromatic polymer/organo-polysiloxane copolymer. Component (B) and/or (C) includes a compound containing a naphthalene ring having a double bond conjugated with an aromatic ring. The composition is easily workable and well adhesive and cures to products having improved mechanical strength, hot-water resistance, low thermal expansion, and minimized water absorption.

Abstract: Compositions containing an aryl phosphite and water to hydrolyze the aryl phosphite provide controlled and extended work time when used as hardening agents for the ambient temperature hardening of phenolic resins and for rapid hardening of such resins at modestly elevated temperatures. Pre-solvolysis with small quantities of water, alkanols of 1 to 4 carbon atoms or alkylene glycols of 2 to 4 carbon atoms improve compatibility of trisubstituted phosphites with the resin. Pre-hydrolysis of the phosphites as well as addition of furfuryl alcohol or alkylene glycols of 2 to 4 carbon atoms accelerate the hardening (curing) of the resin. Various compounds such as: carboxylic acid amides, urea, dicyandiamide, N-methylolated amides, N-alkyl 2-pyrrolidinones having 1 to 4 carbon atoms in the alkyl group, those having an internal epoxide group, alkanols, and Schiff bases retard the ambient temperature hardening of the resin with the aryl phosphite hardening agents.

Abstract: In order to increase the stone chip resistance of automobile finishes aqueous electrocoating paints are used which are produced by the use of a pigment paste which contains as grinding resin an at least partially protonated epoxide-amine adduct which is obtainable by reacting(A) a glycidyl ether of a polyphenol which contains on statistical average at least one epoxide group in the molecule, or a mixture of such glycidyl ethers,(B) a polyglycidyl ether of a polyol which contains on statistical average more than 1.0 epoxide groups in the molecule, or a mixture of such polyglycidyl ethers, and(C) a compound which contains a primary amino group in the molecule or a mixture of such compoundswith each other in such a stoichiometric ratio that an epoxide-amine adduct is obtained in which on statistical average at least 2.

Abstract: Compositions comprising epoxy resins containing one or more rodlike mesogenic moieties per molecule are cured with polyamines containing one or more rodlike mesogenic moieties per molecule. These curable compositions can be oriented by the application of an electric field or magnetic field or drawing and/or shear flow prior to and/or during curing. The resultant cured products exhibit an improvement in one or more physical and/or mechanical and/or thermal properties as compared to a like epoxy resin system which does not contain any rodlike mesogenic moieties.

Abstract: A resin composition for a cationically electrodepositable paint comprising(A) a resin having hydroxyl groups and cationic groups,(B) an epoxy resin having at least 2 epoxy functional groups each of which comprises an epoxy group directly bound to an alicyclic ring and/or bridged alicyclic ring on average per molecule, and(C) a finely divided gelled polymer as principal components, wherein said finely divided gelled polymer is obtained by emulsion polymerizing(C-1) a polymerizable monomer containing at least two radically polymerizable unsaturated groups in the molecule, and(C-2) a radically polymerizable unsaturated monomer other than the one mentioned in (C-1), abovein the presence of a reactive emulsifier containing an allyl group in the molecule.

Abstract: The present invention is directed to a novel epoxy polymeric composition resulting from reacting (A) at least one compound containing an average of more than one epoxide group per molecule with (B) at least one curing agent for component (A). At least a portion of the curing agent (B) is at least a first curing agent compound which contains (a) an average of more than one active amine hydrogen atom per molecule and (b) an average of at least one aromatic ring which contains at least one pendant monovalent electron withdrawing group. The present invention also includes a process for preparing the above polymeric materials. The polymeric materials of the present invention also exhibit nonlinear optical capabilities when formed into an optically transparent medium with a noncentrosymmetric alignment of molecules. The nonlinear optical materials of the present invention are useful in electrooptic devices for use in communications and data-processing.

Abstract: An epoxy resin composition for sealing semiconductor elements comprising o-cresol-novolak type epoxy resins, curing agents, curing accelerators, inorganic fillers, plasticizers and imide-epoxy resins having the formula (I) is disclosed. Use of the imide-epoxy resin in an amount of 0.1 to 20.0% by weight improves the heat and moisture resistant properties of the epoxy resin composition. ##STR1## wherein, R.sub.1 and R.sub.2 denote independently H or (CH.sub.2)nCH.sub.3 radical,n denotes 0 or an integer of 1 above.

Abstract: The present invention is directed to an epoxy-containing polymeric material having nonlinear optical properties, particularly a glycidyl amine polymer, and a process for making the nonlinear optical (NLO) epoxy-containing polymeric material including poling the polymeric material under high voltage at elevated temperature for a period of time to bring about orientation of the nonlinear optical functionalities in the polymer. The polymers have enhanced thermal stability and good NLO properties.

Abstract: An epoxy resin composition for sealing semiconductor elements comprising o-cresol-novolak type epoxy resins, curing agents, curing accelerators, plasticizer and a high performance epoxy resin selected from a group consisting of epoxy resins represented by the formulas (I-a), (I-b) and (I-c) is disclosed.Use of the high performance epoxy resin in an amount of from 0.1 to 20.0% by weight improves the heat and moisture resistance of the epoxy resin composition. ##STR1## wherein, R.sub.1 and R.sub.2 represent independently H or (CH.sub.2) nCH.sub.3 radical, andn represents 0 or an integer of 1 above.

Abstract: Compositions comprising epoxy resins containing one or more rodlike mesogenic moieties per molecule are cured with polyamines containing one or more rodlike mesogenic moieties per molecule. These curable compositions can be oriented by the application of an electric field or magnetic field or drawing and/or shear flow prior to and/or during curing. The resultant cured products exhibit an improvement in one or more physical and/or mechanical and/or thermal properties as compared to a like epoxy resin system which does not contain any rodlike mesogenic moieties.

Abstract: Compositions comprising epoxy resins containing one or more rodlike mesogenic moieties per molecule are cured with polyamines containing one or more rodlike mesogenic moieties per molecule. These curable compositions can be oriented by the application of an electric field or magnetic field or drawing and/or shear flow prior to and/or during curing. The resultant cured products exhibit an improvement in one or more physical and/or mechanical and/or thermal properties as compared to a like epoxy resin system which does not contain any rodlike mesogenic moieties.

Abstract: The present invention discloses a low-temperature curing epoxy resin composition including: an epoxy resin main agent to which unsaturated acid ester of polyhydric alcohol is added and which contains epoxy resin having urethane bonds in the molecules thereof; and a curing agent containing an alicyclic amine compound. This epoxy resin composition may be rapidly cured even at a low temperature and presents a good work efficiency. This epoxy resin composition may be prepared as a cured body excellent in resistance to hot water, mechanical strength, impact resistance and the like.

Abstract: Resin compositions comprising 20 to 50% by weight, based on total composition weight, of a first resin which comprises an acrylate-epoxy oligomer having a molecular weight of from 2000 to 5000; from 2 to 10% of a second resin which comprises an acrylate-urethane oligomer; up to 50% of a third resin which comprises a second acrylate-epoxy oligomer, where from 1 to 5% of the epoxy is an epoxy novolac; from 10 to 40% of a liquid acrylate; from 2 to 20% of a liquid diacrylate having an ether linkage; from 5 to 25% of a liquid alkylene diacrylate; and from 1 to 5% of a UV photoinitiator. The compositions also preferably includes from 0.05 to 1% of a flow control agent. The compositions are applied to substrates such as printed wiring boards and cured with ultraviolet light to form a conformal coating on the substrate.

Abstract: Hardenable mixtures comprising(a) an epoxide resin,(b) a latent epoxide resin hardener which starts to react only at a temperature of at least 80.degree. C. (measured by DSC at a heating rate of 10.degree. C./minute),(c) an amine having at least one amine hydrogen and(d) a thiol having at least one SH group, either the amine (c) having at least two hydrogen atoms bound to one or more nitrogen atoms or the thiol (d) having at least two SH groups, and the difference between the reaction maxima in the DSC diagram at a heating rate of 10.degree. C./minutes being at least 30.degree. C., are suitable for the production of crosslinked products, especially for the production of flexible prepregs having a non-critical B stage and a very good storability.

Abstract: Latent, heat-curable epoxy resin compositions containing metal carboxylate curing systems provide exceptional latency, particularly at elevated temperature, as well as facile curing, high T.sub.g and adhesive strength, and other attractive properties. The metal carboxylates comprise alkali metals and alkaline earth metals, aromatic and aliphatic metal carboxylates. The preferred curing systems comprise synergistic combinations of the metal carboxylates with cure modifiers.

Abstract: A conductive paste composition is described, which comprises an epoxy resin having a diglycidylamino group, a resol type phenol curing agent, and copper powder. The paste composition exhibits excellent moisture resistance and adhesion and provides a cured film of high conductivity level.

Abstract: The present invention relates to novel epoxy resin compositions for sealing semiconductor elements, which comprise 0.1 to 20.0% by weight of imide-epoxy resins represented by the general formula (I) together with epoxy resins, curing agents, curing promoters and plasticizers, and which has improved heat resistant and moisture resistant properties: ##STR1## wherein, R.sub.1 and R.sub.2 represent H or --CH.sub.2).sub.n CH.sub.3 group, andn represents an integer of 0 or 1.

Abstract: An epoxy resin composition for use in carbon fiber reinforced plastics which comprises the following components (A), (B), (C), and (D):(A) an epoxy resin of the bisphenol A diglycidyl ether type;(B) at least one compound selected from the group consisting of dicyandiamide, 2,6-xylenylbiguanide, o-tolylbiguanide, diphenylguanidine, adipyldihydrazide, azelayldihydrazide, and isophthalic acid dihydrazide;(C) a compound represented by general formula (I) ##STR1## wherein X.sub.1 and X.sub.

Abstract: The present invention is directed to an epoxy-containing polymeric material having nonlinear optical properties, particularly a glycidyl amine polymer, and a process for making the nonlinear optical (NLO) epoxy-containing polymeric material including poling the polymeric material under high voltage at elevated temperature for a period of time to bring about orientation of the nonlinear optical functionalities in the polymer. The polymers have enhanced thermal stability and good NLO properties.

Abstract: A liquid expoxy composition containing a diglycidyl ether of a dihydric phenol and/or a diglycidyl ether of a tetrabrominated dihydric phenol, an epoxy with a functionality from 2.2 to 4, cycloaliphatic diamine curing agent, and thixotropic agent; and use thereof to fill drilled through-holes in circuit boards and cards and as isolation border around the edges of a board or card.

Abstract: A powder coating composition is disclosed which includes an epoxy resin which is solid at room temperature, and a curing agent, characterized in that the curing agent includes an adduct obtained by reaction of (a) a polyfunctional epoxy resin, (b) an imidazole compound having a secondary amino group in the imidazole ring thereof and (c) a polyhydric phenol.

Abstract: A liquid epoxy composition containing a diglycidyl ether of a dihydric phenol and/or a diglycidyl ether of a tetrabrominated dihydric phenol, an epoxy with a functionality from 2.2 to 4, cycloaliphatic diamine curing agent, and thixotropic agent; and use thereof to fill drilled through-holes in circuit boards and cards and as isolation border around the edges of a board or card.

Abstract: Epoxy resins are modified by reaction with an acidified polytertiary amine-containing compound. These modified epoxy resins when cured result in products having improved properties.

Abstract: A composition comprising a multifunctional glycidyl ether having at least three epoxy groups per molecule with a hardening amount of a mixture of a rigid aromatic diamine and an aromatic diaminopolysiloxane can be thermally cured to a compatible composition. Glycidylamines cannot be used in this composition. Optionally, a diglycidyl ether can be included.The cured compositions have higher glass transition temperatures than previously observed with epoxy/silicone systems. They also have improved resistance to atomic oxygen over that shown by epoxy formulations lacking a polysiloxane species therein.

Abstract: A curable impact modified epoxy resin mixture suitable for producing high performance composites is composed ofA. an aromatic epoxy compound,B. an amine type curing agent,C. from 10 to 40% by weight of an aromatic thermoplastic oligomer which contains reactive groups, preferably a polyether sulfone, andD. from 0.1 to 10% by weight of a high molecular weight emulsifier, preferably a phenoxy resin, an epoxy resin or a thermoplastic copolymer, which is compatible not only with the epoxy compound A but also with oligomer C.

Abstract: An epoxy resin composition is disclosed that can be cured at a temperature of 150.degree. C. or below, and can be used to provide a high performance carbon fiber composite material having a 0.degree. direction bending strength of 220 kg/mm.sup.2 or over, and an interlayer shear strength of 10 kg/mm.sup.2 or over.The composition is made up of:(A) an epoxy compound containing 10 to 100% by weight of m- or o-methyl-p-N,N-diglycidyl-aminophenyl-ether or its oligomer,(B) diaminodiphenylsulfone and/or diaminodiphenylmethane,(C) dicyandiamide, 2,6-xylenylbiguanide, o-tolylbiguanide, diphenylguanidine, adipil dihydrazide, azelayl dihydrazide, or isophthalic acid dihydrazide, and(D) a urea compound.

Abstract: Heat-curable compositions of matter which are stable on storage and which contain(a) 10-70 parts by weight of an epoxy resin having a functionality of at least 3,(b) 90-30 parts by weight of an epoxy resin having a functionality of 2-2.5,(c) a diphenol, the amount of the diphenol being so chosen that 0.6-1.2 hydroxyl equivalents of the diphenol (c) are employed per epoxide equivalent of the epoxy resins (a) and (b), and(d) 10-150 parts by weight, relative to 100 parts by weight of the components (a) to (c), of a thermoplastic having phenolic end groups and having a glass transition temperature of at least 150.degree. C. which is compatible with the mixture of the components (a) to (c), are particularly suitable for the production of prepregs for fiber-reinforced composite materials or for the production of adhesive films. The cured shaped articles obtained therefrom are distinguished by a high heat distortion point and excellent mechanical strength properties.

Abstract: An epoxy resin composition for semiconductor sealing which comprises, as essential components,(A) an epoxy resin comprising 50-100% by weight, based on total epoxy resin amount, of a polyfunctional epoxy resin represented by the formula (I) ##STR1## wherein n and m are each an integer of 0 or more, n+m=1-10, and R.sub.1, R.sub.2 and R.sub.3 which may be the same or different, are each selected from hydrogen atom, an alkyl group and a halogen atom, with the proviso that all of R.sub.1, R.sub.2 and R.sub.3 must not be hydrogen atom simultaneously,(B) a phenolic resin curing agent,(C) a silica filler, and(D) a curing accelerator.

Abstract: Curable compositions comprise(A) a polyglycidyl ether of a polyhydric phenol,(B) a polyglycidyl ether of a polyhydric alcohol,(C) a nitrogen-containing latent hardener for epoxide resins and(D) as cure accelerator dispersed as a powder in the composition, a solid solution of a polymeric phenol with an aliphatic polyamine having two or more amine groups, each of the amine groups being tertiary and at least two of the amine groups being dimethylamino groups.The compositions are useful as adhesives, sealants, laminating resins and coatings.

Abstract: A low viscosity epoxy resin, i.e., a low viscosity polyglycidyl derivative, of an aminophenol having at least one alkyl group on its aromatic ring of which viscosity is 15 poises or below as measured at 25.degree. C., a resin composition containing said resin, and a fiberreinforced composite material containing as matrix a cured product of said epoxy resin composition and a fiber as reinforcing material.

Abstract: A curable resin composition comprises an epoxy compound and a propargyl aromatic ether.

Abstract: Advanced epoxy resins are disclosed which result from the reaction of a relatively low molecular weight epoxy resin and a polyhydric phenol wherein at least one of the reactants contains at least one halogen atom which is meta with respect to a glycidyl ether group or a hydroxyl group attached to an aromatic ring. These advanced epoxy resins, when cured with a suitable curing agent, possess an improvement as compared to an advanced epoxy resin containing halogen atoms which are ortho with respect to a glycidyl ether group in at least one of thermal stability, glass transition temperature, relationship of viscosity to molecular weight and resistance to forming hydrolyzed halides in the presence of a refluxing solution of an alkali metal hydroxide.

Abstract: Novel tetraglycidates have the formula ##STR1## wherein R.sup.1 and R.sup.2 are independently hydrogen, alkyl of 1 to 8 carbon atoms, perfluoroalkyl, or cycloalkylidene of 5 to 7 carbon atoms. Epoxy resin systems exhibiting good tensile properties and moisture sensitivity can be made by copolymerizing the tetraglycidates with a polyamine curing agent. Prepregs can be made by combining the epoxy resin systems with a fiber reinforcement. The epoxy resin system may include a co-epoxide.