Patent ID: 8299187

Claim:
A method for improving the acoustic impedance of an epoxy resin, said method comprising the steps of: providing an epoxy resin component wherein the resin component comprises a bisphenol A epoxy resin; providing a rubber component wherein the rubber component has a glass transition from −39° C. to −80° C. degrees centigrade, has a molecular weight of 3000 Daltons to 4200 Daltons and comprises up to thirty percent by weight of acrylonitrile; mixing the epoxy resin component with the rubber component wherein the rubber component is added to the epoxy resin component in a concentration of approximately 15 to 30 parts by weight per 100 parts by weight of the epoxy resin component; heating the mixture to a temperature from 72° centigrade to 200° centigrade to react the epoxy resin component with the rubber component; cooling the reacted mixture to an ambient temperature; adding a curing agent to the cooled reacted mixture; and cross-linking the bisphenol A epoxy resin with the curing agent to form a rubber microcomposite having a plurality of spherical rubbery domains within an epoxy resin matrix.