Abstract: The invention relates to powdered lacquers based on a mixture of epoxide compounds and optionally polyesters as well as salts of primary C.sub.4-18 aliphatic and cycloaliphatic-diamines with phosphoric acid and/or sulphuric acid as a hardener, as well as other additives and a method for the manufacture of flat finish coatings.

Abstract: The present invention relates to a new polymer composition having the processing characteristics of a thermosetting polymer along with an improved balance of properties including improved modulus/glass transition temperature/toughness balance. These new polymer compositions are prepared by reacting certain diphenolic compounds with certain diepoxide compounds to form linear units which are lightly crosslinked through the resulting secondary hydroxyl groups. Also disclosed and claimed are processes for preparing such compositions, cured compositions and end-use applications.

Abstract: A rapid curing composition comprising a mixture of (A) a polyepoxide and an amine curing agent and (B) a novel thiocyanate salt of the reaction product of an alkylene polyamine, such as ethylene diamine, and a bicyclic amide acetal and a method for curing said composition are described.

Abstract: Viscous oligomeric epoxy resins can be quickly cured at temperatures of 100.degree. C. by incorporating a hardener that is a blend of (a) the oligomeric reaction product of bisphenol A and bisphenol A monoglycidyl ether and (b) an imidazole. The cured resins are tough and resistant to both moisture and high temperatures. Prepregs, in which glass, graphite or polymeric organic fiber sheets are saturated with these resins, are particularly useful in the repair of damaged aircraft and aerospace structures.

Abstract: Storage-stable, thermally-curable, one-part epoxy resin compositions comprising a curable opoxide resin; a curative amount of an aliphatic or non-aromatic cyclic polyol having about 2 to 18 carbon atoms, at least two hydroxy groups of said polyol being primary or secondary, and said polyol being free of strong acid groups, and free of electron-withdrawing substituents and large groups which cause steric hindrance in the .alpha.-position in relation to the carbon atoms attached to the methylol groups of the polyol; and a catalytic amount of an imidazole compound.

Abstract: A phenolic curing agent for epoxy resin powder coatings is prepared by combining (a) a linear phenolic hydroxyl-terminated resin having a weight per phenolic within the range of about 650 to about 8,000, preferably about 850 to about 950, (b) a dihydric phenol present in an amount such that the weight per hydroxyl of the mixture of (a) and (b) is within the range of about 240 to about 280, and (c) at least about 2 weight percent, based on the weight of the composition, of an imidazole cure accelerator. The described imidazole-accelerated curing agent is less susceptible to melting point depression and to sintering with storage than conventional imidazole-containing phenolic curing agents. The dihydric phenol-terminated epoxy resin is preferably prepared by reacting a dihydric phenol with a linear diepoxy resin in the presence of a phosphonium halide catalyst so as to produce a phenolic hydroxyl-terminated resin having a weight per hydroxyl within the range of about 650 to about 8,000.

Abstract: An adhesive composition comprising a mixture of a polyepoxide, an amine curing agent and a thiocyanate salt of a compound having the formula ##STR1## wherein R represents an alkyl group having from 1 to 20 carbon atoms, an aryl group having from 6 to 20 carbon atoms or an alkaryl group having from 7 to 20 carbon atoms, R', R" and R'" independently represent hydrogen, an alkyl group having from 1 to 10 carbon atoms or an alkyl ether group having from 1 to carbon atoms and n represents 2 or 3 is described.

Abstract: A process for accelerating the cure rate of a mixture comprising an epoxy resin and an amine hardener comprising including in the mixture from 0.5% to 15% by weight of a catalyst which is the reaction product of a bicyclic amide acetal and ammonium thiocyanate and curing the resulting mixture at a temperature of from about abient temperature to about 120.degree. C. is described.

Abstract: An epoxy resin system is disclosed which is especially adapted for use in the pultrusion process. Such resin system comprises tris (hydroxyphenyl) methane-based epoxy resin and a combination of the cross-linking agents (methyl)-bicyclo(2,2,1) heptane-2,3-dicarboxylic anhydride and poly sebacic poly anhydride, the ratio of the dicarboxylic anhydride to the total amount of cross-linking agents ranging from 0.65 to 0.80 and the ratio of the poly anhydride to the total amount of cross-linking agents ranging from 0.35 to 0.20. The amount of total cross-linking agents to epoxy resin ranges from about 60 to about 80 parts total cross-linking agents, per 100 parts resin, by weight. A small amount of an imidazole accelerator, preferably 2-ethyl-4 methyl imidazole, is included.

Abstract: Novel solid, crystalline complexes of triethylene diamine and a polyphenol compound such as Bisphenol-A and the use of these complexes in the curing of polyepoxides and polyisocyanates are described.

Abstract: New and improved heat curable compositions are disclosed comprising epoxidic prepolymers and mono- and di-imidazole-carboxamides. The compositions are stable at room temperature, but cure readily at moderate temperatures of substantially less than about 250.degree. F., preferably at about 180.degree. F. to about 200.degree. F. and especially preferably at about 160.degree. F. to about 180.degree. F. The cured neat resins are useful as adhesives and as matrix resins in reinforced composites, with excellent physical properties.

Abstract: A tough, durable, high temperature epoxy tooling composition for making cast-to-size forming tools. The composition comprises a bisphenol-A epoxy, a trifunctional aromatic epoxy, an anhydride catalyst, and an imidazole catalyst. The composition may optionally contain a filler system comprising filler particles having different diameters that are interstitially-matched.

Abstract: 2,6-Disubstituted 4-epoxypropyl glycidyl ethers of the formula ##STR1## wherein X is a group R' or X is a group of the formula ##STR2## and each of R and R' independently of the other is C.sub.1 -C.sub.4 alkyl, C.sub.1 -C.sub.4 alkoxy, a halogen atom or C.sub.6 -C.sub.10 aryl, can be used, together with customary epoxy resin hardeners, for the preparation of cured products, in particular for application in the electronics industry, or as adhesives. Compounds of the formula are also valuable reactive diluents for curable epoxy resin mixtures.

Abstract: A two-part composition curable by contact of respective parts with one another, comprising: a first part comprising a cationically polymerizable material and a first latent curing component; and a second part comprising a cationically polymerizable material and a second latent curing component which is reactive with the first component to form cations which are curingly effective for the resin. A preferred class of cation species comprises carbenium ions derived from reaction of organic halide compounds, as the first component, with silver salts of non-nucleophilic anions, e.g., SbCl.sub.6.sup.-, SbCl.sub.3.sup.-, SbF.sub.6.sup.-, AsF.sub.6.sup.-, SnCl.sub.5.sup.-, PF.sub.6.sup.-, BF.sub.4.sup.-, CF.sub.3 SO.sub.3.sup.- and ClO.sub.4.sup.-, as the second component, The respective parts of the two-part composition may be applied to matable surfaces which then are contacted to effect rapid bonding cure of the composition.

Abstract: This invention relates to the use of compositions of the formula: ##STR1## wherein n is 2 to 4 and X is --O--, --S-- or ##STR2## wherein R.sub.1 is an aliphatic or aromatic moiety as a curing agent for epoxy resins to form a thermoset material which has a reduced shrinkage.

Abstract: Cyclic amidines which are modified by the incorporation of additional polar groups, may be used as catalysts for hardening heat-curable resin compositions comprising polyepoxides and optionally carboxyl group-containing polymers. Such amidine catalysts yield a high reactivity, an excellent storage stability and result in elastic coatings which show a high gloss and a good resistance to solvents.

Abstract: Amidines of the formula: ##STR1## wherein R.sub.1 and R.sub.2 are alkyl groups and the sum of the carbons in R.sub.1 and R.sub.2 is from 2 to 16 are produced by cyanoethylation of the lactam: ##STR2## wherein R.sub.1 and R.sub.2 are as defined above, followed by reduction and, finally, cyclization by dehydration. The compounds produced are useful for curing epoxy and urethane resins.

Abstract: The invention relates to a substantially anhydrous composition containing(a) an epoxy resin,(b) as hardener for the epoxy resin, the product obtained (i) by finely homogenizing (1) dicyandiamide and (2) urea by grinding (1) and (2) together or dissolving (1) and (2) in a common solvent, or (ii) by melting (1) and (2) together or (iii) by partially reacting (1) and (2) in a common solvent, the weight ratio of (1) and (2) being in the range from 4:1 to 1:4, and, optionally,(c) a curing accelerator.The compositions are suitable in particular for the preparation of coatings, preferably as powder coating compositions, and are distinguished by a very good relationship between levelling and reactivity, and the cured coatings have excellent stability to solvents and boiling water as well as excellent mechanical properties.

Abstract: Heat-curable compositions are described, comprising(a) an epoxide resin and(b) an effective amount of a urea of formulaAr--NHCON(R.sup.3)R.sup.4whereAr represents an aromatic group linked through an aromatic carbon atom to the indicated nitrogen atom and which is substituted by an amido group, andR.sup.3 and R.sup.4 each represent an aliphatic, cycloaliphatic, or araliphatic hydrocarbyl group, optionally substituted by a halogen atom or a hydroxyl group, or R.sup.3 may further represent a hydrogen atom, or R.sup.3 nd R.sup.4, together with the indicated nitrogen atom, may represent a heterocyclic ring of 3 to 5 carbon atoms which may also have one oxygen atom in the ring.Such amidoarylureas may be used alone with the epoxide resin, or in combination with an accelerator for the heat-curing reaction, selected from dicyandiamide, carboxylic acid hydrazides, succinimide, cyanoacetamide, 1-cyano-3-(lower alkyl)guanidines, imidazoles, and carboxylic acid-tertiary amine salts.

Abstract: Hydroxyaromatic compounds are amido-alkylated or cyano-alkylated to form the corresponding compounds by:(a) heating said compounds with an alkylating agent in the presence of water and a catalyst, e.g., benzyltrimethylammonium chloride;(b) adding an alkaline agent, e.g., NaOH, to the heated mixture of (a); and(c) continuing to heat the resulting mixture until the corresponding amido- or cyano-alkylated compound is formed.Fully or partially amido-alkylated compositions are useful in the preparation of copolymers with epoxy resins.

Abstract: Epoxy resins are prepared by dehydrohalogenating the reaction product of a polyhydric phenol with an excess of an epihalohydrin in the presence of a quaternary ammonium compound wherein prior to dehydrohalogenation, the excess epihalohydrin is removed and an organic solvent is added and at least a portion of the dehydrohalogenation is conducted in the presence of added quantities of a quaternary ammonium compound.

Abstract: Heat-curable mixtures, containing (a) an epoxide resin having on average more than one epoxide group in the molecule, (b) an allyl-substituted or methallyl-substituted imide of the formula I ##STR1## in which E is allyl or methallyl, G is hydrogen or methyl, n is 1 or 2, and R is hydrogen, alkyl, alkenyl, cycloalkyl, aryl, benzyl or arylene, and (c) a curing catalyst, have good storage stability and processability and produce moulded materials having high mechanical strength values and good resistance to heat.

Abstract: Storage stable, heat curable mixtures obtained from epoxy resins as a binder system containing latent hardening agents as well as fillers and additive materials which have outstanding mechanical and electrical properties and which are obtained as epoxy resin components of an adduct of a high molecular solid epoxy resin and 4,4'-diaminodiarylalkane in a molecular ratio of 1:0.01 to 0.05. The preferred economical curing agent is a phenol formaldehyde condensation product.

Abstract: A highly fluid, solventless heat curable resin is formulated from an admixture comprising a polyglycidyl aromatic amine, a polycarboxylic acid anhydride curing agent, and a curing accelerator. The heat curable formulation exhibits low viscosity and is useful as an encapsulant and insulation for electrical members exposed to high electrical stress. Magnetic coils encapsulated with the cured formulation resist corona discharge at electrical stresses in excess of 2100 volts per mil.

Abstract: A curable composition consisting ofA. 100 parts by weight of an epoxy resin,B. from 4 to 100 parts by weight of a conventional curing agent for epoxy resins, andC. from 0.1 to 5 parts by weight of an N-acylimidazole which possesses an aromatic acyl component which is substituted at the two positions ortho to the carbonyl groupcan be used to produce moldings, coatings, finishes, adhesives and composite fiber materials.

Abstract: Epoxy resins are prepared by reacting a mixture of (A) a diglycidyl ether of a dihydric aliphatic material, (B) a polyglycidyl ether of a polyhydric phenol having an average of at least about 2.6 glycidyl ether groups per molecule and optionally (C) a diglycidyl ether of a dihydric phenol with a dihydric phenol in the presence of a catalyst.Coating compositions containing the aforementioned epoxy resins have improved chip resistance, chemical resistance or pencil hardness when cured.

Abstract: Metal, preferably divalent copper, cobalt or nickel, phthalocyanine tetraamines are used as curing agents for epoxides. The resulting copolymers have high thermal and chemical resistance and are homogeneous. They are useful as binders for laminates, e.g. graphite cloth laminate.

Abstract: A method of making an epoxy prepolymer curing agent is disclosed. The method comprises the steps of reacting a mixture of piperidine and an epoxy resin so as to form an epoxy prepolymer adduct. The adduct is mixed with 2-ethyl-4-methylimidazole thereby forming the curing agent composition.

Abstract: Described herein are curable molding compositions comprising an epoxide resin, a polyol and particular catalysts. These compositions have good pot life and cure rapidly.

Abstract: Liquid epoxy resin hardeners are mixtures of 2-ethyl-4-methylimidazole, ethyldimethylimidazole and/or diethylmethylimidazole isomers which can also contain other alkylimidazoles, and can be produced by distillation of the products obtained in the dehydrogenation of 2-ethyl-4-methylimidazoline.

Abstract: Molding materials, laminates, stratified material and cover or protective layers which are of high electrical and mechanical quality are formed from polymerisable epoxy compounds if the corss-linking of the epoxy resins is accomplished by anionic polymerisation, using mixed catalysts of tertiary amines of the formula: ##STR1## and an imidazoles of the formula: ##STR2## as a polymerisation catalysts.

Abstract: A novel diepoxide curing agent is revealed. The curing agent comprises a mixture of an imidazole compound and a selected polyoxyalkylenepolyamine.This curative produces an epoxy resin of low viscosity with a prolonged pot life. They find particular usefulness in filament winding and pultrusion processes where they are used to fabricate articles of considerable strength.

Abstract: A polyglycidyl derivative of an aromatic diamine, aminophenol, or polyphenol and a diglycidyl ether of a bisphenol are reacted with a bisphenol, in the presence of a catalyst at elevated temperature, to yield a reaction product wherein each glycidyl group is effectively endcapped with a moiety containing a free hydroxyl group. The ratio of equivalents of polyglycidyl compound to diglycidyl compound is 1 to 4 to 1 to 1, and of bisphenol to total glycidyl compounds is 1.8 to 1 to 2.4 to 1. Said product is useful for curing solid epoxy resins. The epoxy resins cured by said product have a dense crosslinked network resulting in concomitant superior coating properties especially chemical resistance while maintaining good flexibility.

Abstract: The disclosure relates to a novel compound 4,4'-methylene-bis-(2-ethyl-5-methyl imidazole) represented by the structural formula ##STR1## A method is provided for producing the novel compound subjecting formaldehyde or a methylenizing agent to thermal reaction with 2-ethyl-4-methyl imidazole in the presence of a catalyst; and a method of curing an epoxy compound and a method of accelerating curing the epoxy compound and a method of inhibiting crystallization of 2-ethyl-4-methyl imidazole, respectively by use of the new compound.

Abstract: Cyclic amidines which are modified by the incorporation of additional polar groups, may be used as catalysts for hardening heat-curable resin compositions comprising polyepoxides and optionally carboxyl group-containing polymers. Such amidine catalysts yield a high reactivity, an excellent storage stability and result in elastic coatings which show a high gloss and a good resistance to solvents.

Abstract: A novel composition is described comprising an admixture of an unsaturated polyimide prepolymer essentially free of terminal amine groups and an epoxy resin having a homopolymerization temperature that is greater than the temperature at which the polyimide polymerizes. These compositions maintain the superior glass transition temperatures and moisture resistance of the polyimide while picking up the desirable handling properties of the epoxy. These compositions have excellent high temperature and moisture resistant properties and excellent storage stability. For instance, carbon composites made with these materials have exhibited 60% shear property retention at 450.degree. F. after being boiled in water for one week. Also described are prepregs comprising the novel composition, methods for curing the novel composition to obtain the superior properties, and articles of manufacture comprising the novel composition.

Abstract: Epoxide resins are cured by heating with a hydroxyphenylurea of formula ##STR1## where R.sup.2 denotes --NH.sub.2, --NO.sub.2, --Cl, --Br, or alkyl, p denotes zero, x and y each denote zero or 1, and the sum of x+y is 1. Such hydroxyphenylureas may be used alone, as accelerators for heat-curing with other agents such as dicyandiamide, melamine, and carboxylic acid hydrazides, or may be used as the primary curing agent with promoters such as dicyandiamide, melamine, and carboxylic hydrazides.

Abstract: A compound containing an epoxy group, is reacted with a carboxyl compound by heating a mixture of these compounds in the presence of a benzotriazole such as unsubstituted benzotriazole or tolyltriazole as accelerator. The accelerator is particularly effective in the reaction of a carboxyl compound which is a polyester containing free carboxylic acid groups with an epoxy compound which is triglycidyl cyanurate or an epoxy resin based on bisphenol A.

Abstract: A catalyst and accelerator for an epoxy system which consists of a halogeisphenate of a catalytically active tertiary amine and which is obtained in a solid form practically water insoluble and odor free but which nevertheless possess the catalytic activity of the tertiary amine. The application describes the proportion of the catalyst by reacting an aqueous suspension of the halogenobisphenol with the tertiary amine, the proportion of epoxy resin systems containing the catalyst and the epoxy resin systems thus formed.

Abstract: A tough epoxy polymer is formed by pre-reacting a poly(oxypropylene) diol or triol with a chemical excess of an anhydride curing agent for epoxy resins. The resulting diester-diacid is then polymerized with an epichlorohydrin-bisphenol A epoxy resin. Suitable imidizole catalysts are preferred for the reactions.

Abstract: An epoxy resin composition comprising (a) an epoxy resin, (b) a lactone obtained by decarboxylation condensation reaction of a saturated alicyclic 1,2-dicarboxylic acid anhydride, and if necessary (c) a curing agent for the epoxy resin and (d) a curing accelerator gives a cured article showing almost no or very slight curing shrinkage.

Abstract: A curable composition comprising an epoxy resin or a monoepoxide and a curing agent comprising a metal salt complex of an adduct of an imidazole and a monofunctional epoxy compound.

Abstract: Epoxy resin compositions are disclosed which are the reaction products resulting from reacting (A) the reaction product of a cyanuric halide and at least one dihydric or polyhydric phenol with (B) at least one dihydric or polyhydric phenol and (C) at least one epoxy resin having an average of more than one epoxy group per molecule. These epoxy resin compositions are suitable for use as electrical laminates, structural laminates, coatings, castings, electrical encapsulation and the like.

Abstract: The present invention is directed to storage-stable precatalyzed polyepoxides containing a catalytic amount of an ammonium salt and to a process for preparing higher molecular weight polyepoxides by reacting the precatalyzed polyepoxide with a polyhydric phenol or polymeric fatty acid.

Abstract: The advancement method, i.e., the preparation of epoxide resin mixtures by reaction of compounds containing 2 to 4 phenolic hydroxyl groups with a stoichiometric excess of polyepoxide compounds in the presence of a catalyst, comprises adding glycidol as a chain stopper. The products are used in various industrial fields, for example in surface protection.

Abstract: A one-part epoxy adhesive has been developed that cures rapidly at relatively low elevated temperatures and is based on a diglycidyl ether of bisphenol A (DGEBA), DGBE reacted with glycerol and natural oils, and a unique triple catalyst system of metal imidazole salt, dicyandiamide and a cyclic latent curing agent that liberates diethylenetriamine when heated.

Abstract: Novel imidazolides (N-acylimidazoles) of the formula I ##STR1## wherein R.sub.1 is hydrogen, C.sub.1 -C.sub.12 -alkyl or phenyl, and R.sub.2 is hydrogen, orR.sub.1 is ethyl, and R.sub.2 is methyl, orR.sub.1 is hydrogen, and R.sub.2 is phenyl or methyl, andR.sub.3 is a group of any one of the formulae II-VI ##STR2## wherein X.sub.1 is hydrogen, chlorine or NO.sub.2, and X.sub.2 is hydrogen or NO.sub.2.The imidazolides are suitable as curing agents for polyepoxide compounds.

Abstract: New amidine/isocyanate adducts are particularly useful as catalysts for hardening epoxy resins, in particular pulverulent coating compositions based on epoxy resins. New bicyclic amidines are excellent starting materials for manufacturing these amidine/isocyanate adducts.

Abstract: A method and composition have been developed for providing wear resistant surfaces on tools used to stamp sheet metal. The composition is based on liquid epoxy novolac resin having a functionality greater than two filled with an inorganic powder having very high hardness. The epoxy constituent is cross linked and cured in two stages: it is first cured at room temperature with an aliphatic amine curing agent until it is hardened and is then toughened by an elevated temperature cure initiated by an imidazole curing agent. The composition may be used to cast an entire tool or as a surface coating layer for a less durable base.

Abstract: This invention provides a coating composition comprising at least one 1,2 epoxy resin, a modified imidazole catalyst, and a polyfunctional phenol or polyfunctional acid or dicyandiamide.