Abstract: A flame retardant phosphorus element-containing epoxy resin composition substantially free of halogen, including: (I) a non-halogenated epoxy resin material selected from: (A) a non-halogenated phosphorus element-containing epoxy resin; (B) a mixture of: (1) a non-halogenated, non-phosphorus element-containing epoxy resin, and (2) a phosphorus element-containing compound; or (C) the reaction product of: (1) a non-halogenated epoxy resin; and (2) a phosphorus element-containing compound; or (D) a combination of two or more of components (A) to (C); and (II) (A) a multi-functional phenolic crosslinking agent having a hydroxy functionality of at least 2; (B) a material which forms a multifunctional phenolic crosslinking agent having a hydroxy functionality of at least 2, upon heating or (C) a mixture of components (A) and (B); in an amount of from about 50% to about 150% of the stoichiometric amount needed to cure the epoxy resin.

Abstract: An epoxy resin composition comprises a) a polyepoxide, b) a cure inhibitor of boric acid, a Lewis acid derivative of boron, an alkyl borane, a mineral acid having a nucleophilicity value “n” of greater than zero and less than 2.5, or an organic acid having a pKa value of 1 or more, a catalyst which can be complexed with the cure inhibitor, and c) more than 30 parts by weight per 100 parts by weight of polyepoxide of a cross-linker such as a polycarboxylic acid or anhydride including a copolymer of an ethylenically unsaturated anhydride and a vinyl compound, or a hydroxy-functional compound such as a copolymer of styrene and hydroxystyrene.

Abstract: A controlled conversion resin having an epoxy functionality of greater than 2 and comprising moieties derived from epoxy resin, dihydric phenol, acid anhydride, or amine. The resin is prepared by reacting an epoxy resin with a dihydric phenol, an acid anhydride, or amine or other branching agent in the presence of a catalyst and terminating the reaction at a point such that the reaction product contains both epoxy and terminal hydroxyl groups.

Abstract: The invention is a formulation that contains: (1) a low-viscosity epoxy resin; (2) a phenolic chain extender whose concentration is less that 0.6 equivalents phenolic hydroxyl group per equivalent of the low-viscosity epoxy resin; (3) a catalyst that promotes self-curing reactions between epoxy groups; (4) an inhibitor that inhibits the activity of the catalyst under “B-staging” conditions; (5) less than 25 weight percent of a volatile organic solvent; and (6) optionally, a multifunctional cross-linking agent. The formulation contains low levels of volatile organic solvent, and can be used to make electrical laminates. It builds molecular weight controllably in B-staging, so that dripping is avoided but the prepreg can be easily laminated.

Abstract: A controlled conversion resin having an epoxy functionality of greater than 2 and comprising moieties derived from epoxy resin, dihydric phenol, acid anhydride, or amine. The resin is prepared by reacting an epoxy resin with a dihydric phenol, an acid anhydride, or amine or other branching agent in the presence of a catalyst and terminating the reaction at a point such that the reaction product contains both epoxy and terminal hydroxyl groups.

Abstract: A resin composition including from about 1 to about 100 weight percent of a thermoplastic oxazolidone ring-containing compound having a molecular weight of at least 5000, which is the reaction product of: a) from about 20 to about 43 weight percent, based on the polyepoxide and polyisocyanate reactants, of a polyisocyanate having an isocyanate-functionality of from about 1.8 to about 2.2; b) from about 80 to about 57 weight percent, based on the polyepoxide and polyisocyanate reactants, of a polyepoxide having an epoxide functionality of from about 1.8 to about 2.2; and optionally, c) a chain extender. The resin composition is used as an adhesive to adhere a copper foil to a prepreg or a laminate, with improved peel strength and Tg.

Abstract: A heat curable thermosetting epoxy resin formulation useful for making prepregs and electrical laminates containing a viscosity modifier, wherein the viscosity modifier is:

Abstract: A flame retardant epoxy resin composition containing not more than 10% by wgt. of halogen, comprising an epoxy resin, stated concentrations of phosphoric acid ester, nitrogen—containing cross-linking agent having an amine functionality of at least 2 and a catalyst capable of promoting the reaction of the phosphoric acid ester with the epoxy resin and promoting the curing of the epoxy resin with the cross-linker, and optionally a Lewis acid in a stated amount.

Abstract: A heat curable thermosetting epoxy resin formulation useful for making prepregs and electrical laminates containing a viscosity modifier, wherein the viscosity modifier is: (a) an optionally substituted polymer of a monovinylidene aromatic monomer, optionally having one or more further unsaturated monomers copolymerized therewith; (b) an optionally substituted polyphenylene oxide; or (c) an oxazolidone ring-containing compound.

Abstract: A formulation which contains:(1) the nucleophilic addition adduct of an imidazole and an unsaturated compound, which contains more than one imidazole moiety per molecule; and(2) an epoxy resin,is characterized in that fewer than 50 equivalent percent of the imidazole moieties in the adduct are neutralized with acid. The adduct may serve as a curing catalyst in high or low-temperature curing. The formulation is made and applied as a powder coating for coatings or as a matrix resin in laminates. It may be used in solvent-borne or liquid systems.

Abstract: A class of compounds which inhibits the reaction of a polyepoxide with a curing agent at low temperatures including an epoxy resin composition containinga) a polyepoxide;b) an amine or amide curing agent for the polyepoxide;c) at least about 15 meq (per equivalent of polyepoxide) of a catalyst for the reaction of the polyepoxide with the curing agent; andd) a cure inhibitor selected such that:(1) at about 171.degree. C. the composition has a gel time that is at least about 50 percent longer than a similar composition without the inhibitor, and(2) at about 175.degree. C. and higher the composition cures in no more than about 50 minutessuch that the composition cures rapidly with high cross-link density because it has a high catalyst loading, while the inhibitor lengthens the gel time to permit laminating and other processing.

Abstract: A method of preparing epoxy parts wherein the interval of low viscosity of an amine-hardened epoxy system can be extended without sacrifice of cure time. Suitable catalysts for the epoxy-amine hardener reaction are generated in situ. As an advantage, more epoxy articles may be prepared with a given mold capacity having improved wet-out of fiber reinforcement attributed to a larger interval of low viscosity.

Abstract: The invention pertains to a composition useful for curing a polyepoxide or advanced epoxy resin consisting essentially of (A) a curing agent capable of reacting with a polyepoxide at elevated temperatures; and (B) boric acid in an amount of from about 0.01 to about 2.0 parts of polyepoxide.

Abstract: In summary, the invention is related to the discovery of a class of compounds which inhibits the reaction of a polyepoxide with a curing agent at low temperatures. More particularly the invention relates to an epoxy resin composition comprisinga) a polyepoxide; andb) a cure inhibitor comprising boric acid.

Abstract: In summary, the invention is related to the discovery of a class of compounds which inhibits the reaction of a polyepoxide with a curing agent at low temperatures. More particularly the invention relates to an epoxy resin composition comprisinga) a polyepoxide; andb) a cure inhibitor comprising boric acid or maleic acid.In another embodiment, the invention comprises an epoxy resin composition comprisinga) a polyepoxide;b) a cure inhibitor comprising boric acid or maleic acid,c) a curing agent without phenolic hydroxyl moieties, andd) optionally a catalyst for the reaction of the polyepoxide with the curing agent.In still another embodiment the invention relates to a composition useful for curing a polyepoxide which comprisesa) a curing agent capable of reacting with a polyepoxide at elevated temperatures; andb) an inhibiting amount of boric acid or maleic acid; and optionallyc) a catalytic amount of a catalyst useful for accelerating the reaction of a polyepoxide with the curing agent.

Abstract: Epoxy-terminated polyoxazolidone having from about 5 to about 30 weight percent of the isocyanate content are described. These polyoxazolidone are prepared by a process in which various process parameters are controlled in a targeted manner to give a product having from about 50 to about 100 percent of isocyanate groups converted to oxazolidone rings and from about 0 to about 50 percent of the isocyanate groups converted to isocyanurate rings. These epoxy terminated polyoxazolidones exhibit high glass transition temperatures and high resistance to chemicals when cured. They are useful for the preparation of electrical laminates, particularly laminates used in the preparation of electrical circuit boards.