POLYAMIDE FIBER REINFORCEMENT IN THERMOSET POLYURETHANE COMPOSITES

摘要

Fiber-reinforced thermoset polyurethane composites display enhanced impact strength when sufficient amounts of a high tenacity aliphatic polyamide fiber characterized by a drawn denier of 4 to 8 denier per filament; a thermal shrinkage of up to about 14 percent; an elongation of from less than 28 percent; and a tenacity of at least 5.5, preferably at least 7 grams per denier, are incorporated into the composite. The process of producing such composites, including reinforced reaction injection molding processes, resin transfer molding processes, and casting process are improved by a reduction in equipment wear resulting from the incorporation of the specified polyamide fiber.