Reinforced nylon 6 block copolymers

Abstract Nylon block copolymers (NBC), a family of reaction injection molding (RIM) resins commercially introduced during the past year, offer new and valuable balances of properties. The polymers are comprised of alternating blocks of soft rubber segments and hard nylon 6 blocks which are chemically bound together and form discrete, incompatible phases. Glass reinforcement afforded increased resistance to expansion from moisture absorption and thermal changes, along with decreased temperature‐modulus response and increased heatsag resistance. Losses in impact strength from reinforcement addition were shown to be partially restored by moisture absorption and/or changes in resin matrix formulations.