초록 ▼

A method for flexibilizing an epoxy resin is disclosed which comprises (a) preparing a dicarboxy-terminated prepolymer by reacting a carboxylic anhydride with a polybutadiene having a minor amount of pendant vinyl groups at a temperature from about 125°to about 140°F.; (b) reacting the prepolymer wi

A method for flexibilizing an epoxy resin is disclosed which comprises (a) preparing a dicarboxy-terminated prepolymer by reacting a carboxylic anhydride with a polybutadiene having a minor amount of pendant vinyl groups at a temperature from about 125°to about 140°F.; (b) reacting the prepolymer with an excess of liquid epoxy resin at a temperature from about 180°to about 200°F.; (c) adding a vinyl monomer in an amount of about 2% to about 25% of the mixture; and (d) adding epoxy and vinyl polymerization catalysts to cure the mixture.

대표청구항 ▼

A method for flexibilizing an epoxy resin having at least two terminal epoxy groups comprising: (a) preparing a dicarboxy-terminated prepolymer by reacting a stoichiometric excess of a carboxylic anhydride with each hyroxyl equivalent of a polybutadiene having terminal allylic hydroxyl groups and a

A method for flexibilizing an epoxy resin having at least two terminal epoxy groups comprising: (a) preparing a dicarboxy-terminated prepolymer by reacting a stoichiometric excess of a carboxylic anhydride with each hyroxyl equivalent of a polybutadiene having terminal allylic hydroxyl groups and a minor amount of pendent vinyl groups, at a temperature of from about 125°to about 140°and for a time sufficient for substantially all of the terminal hydroxyl groups to form first ester linkages with anhydride molecules resulting in a prepolymer having a functional carboxyl group at each end; (b) reacting an excess of a liquid epoxy resin with each carboxyl equivalent of the dicarboxy-terminated prepolymer at a temperature of from about 180°F. to about 200°F. for a time sufficient to yield an elastomerically modified resin having at least two terminal epoxy groups, the epoxy resin in such elastomerically modified resin being linked to the prepolymer via a second ester linkage; (c) mixing a vinyl monomer in an amount of from about 2% to about 25% by weight of the elastomerically modified resin with the elastomerically modified resin to yield an uncured product; and (d) mixing epoxy and vinyl polymerization catalysts to the uncured product to effect epoxy copolymerization and vinyl copolymerization to thereby yield a cured flexibilized resinous mass.