Abstract: A blend of epoxy resins includes a) an epoxy resin composition derived from the reaction of a liquid epoxy resin, a carboxyl terminated butadiene (CTB), and a carboxyl terminated polybutadiene-acrylonitrile (CTBN) and/or a random and terminal carboxyl functional polybutadiene-acrylonitrile (CTBNX), and b) unreacted epoxy resin. The carboxyl terminated butadiene is miscible with the unreacted epoxy resin and does not separate therefrom even upon aging. Upon cure as with a latent cure agent, a toughened epoxy resin is produced having unexpected good low temperature properties such as peel strength.

Abstract: A non-functional liquid rubber is prepared by the solution polymerization of vinyl monomers. The polymer may be a homopolymer or a copolymer. As a copolymer the preferred monomers are a conjugated diene and a vinyl substituted nitrile such as acrylonitrile or methacrylonitrile. A non-functional initiator is employed that is either an azo initiator or a peroxide initiator.

Abstract: Curable epoxy resins are toughened with statistical monofunctional carboxyl, amine or epoxy terminated reactive polymers and have low viscosities before cure thereby making them useful in a wide range of applications. The cured epoxy resin systems which are modified by the statistical monofunctional reactive polymers have physical properties, such as adhesion and elongation, generally equal to or better than those of cured epoxy resin systems modified with statistical difunctional reactive polymers. A process of preparation for the modified epoxy resin systems of the present invention includes admixing an epoxy resin with a statistical monofunctional carboxyl, amine, or epoxy-terminated reactive polymer in the presence of a curing agent and reaction therewith to form the toughened, cured epoxy resin system.

Abstract: Unsaturated polyester resins of the type already having reactive liquid polymers reacted into the backbone of the resins, are cured in the presence of a reactive liquid polymer additive admixed with the prereacted unsaturated polyester resin. Heating of this system during cure causes the reactive liquid polymer additive to miscibilize with the unsaturated polyester resin. The unsaturated polyester resin modified in the manner described above shows a significant enhancement in toughness as measured by fracture energy over unmodified counterparts or counterparts modified by known methods of adduction or admixing alone.

Abstract: Curable epoxy resins are toughened with statistical monofunctional carboxyl, amine or epoxy-terminated reactive polymers and have low viscosities before cure thereby making them useful in a wide range of applications. The cured epoxy resin systems which are modified by the statistical monofunctional reactive polymers have physical properties, such as adhesion and elongation, generally equal to or better than those of cured epoxy resin systems modified with statistical difunctional reactive polymers. A process of preparation of the modified epoxy resin systems of the present invention includes admixing an epoxy resin with a statistical monofunctional carboxyl, amine, or epoxy-terminated reactive polymer in the presence of a curing agent and reaction therewith to form the toughened, cured epoxy resin system.

Abstract: Curable epoxy resins are toughened with statistical monofunctional carboxyl, amine or epoxy terminated reactive polymers and have low viscosities before cure thereby making them useful in a wide range of applications. The cured epoxy resin systems which are modified by the statistical monofunctional reactive polymers have physical properties, such as adhesion and elongation, generally equal to or better than those of cured epoxy resin systems modified with statistical difunctional reactive polymers. A process of preparation for the modified epoxy resin systems of the present invention includes admixing an epoxy resin with a statistical monofunctional carboxyl, amine, or epoxy-terminated reactive polymer in the presence of a curing agent and reaction therewith to form the toughened, cured epoxy resin system.

Abstract: The present invention generally relates to statistical monofunctional terminated reactive liquid rubbers including a statistical monofunctional carboxylic-terminated reactive liquid rubber, a statistical monofunctional amine-terminated reactive liquid rubber, and a statistical monofunctional epoxy-terminated reactive liquid rubber. These polymers are pourable, making them useful in a variety of applications particularly as toughening agents for epoxy resins to which they impart good physical properties.

Abstract: The novel aspect of this invention resides in co-reacting a toughening agent with components of an unsaturated polyester resin in order to introduce the toughening agent into the backbone of the unsaturated polyester resin and thus produce a toughened stable resin. Suitable toughening agents are carboxyl and hydroxyl terminated reactive liquid polymers which are used in amount of 1 to 30, preferably 1 to 15 parts by weight per 100 parts by weight of reactant monomers used to prepare the polyester resin.