No abstract

Sandwich-type layered composite material was prepared with epoxy beam and polyurethane copolymer that was synthesized from 4,4-methylene bis (phenylisocyanate), poly(tetramethyleneglycol), and 1,4-butanediol as a chain extender. As for the polyurethane, shape recovery was improved with higher content of hard segment, and the highest damping effect as judged by tan ␦ was observed at 30 -35% hard segment. The composite material had better impact strength and higher tan ␦ than epoxy beam alone, but the superiority became less as more hard segment was incorporated. The interfacial binding force between polyurethane and the epoxy beam also decreased in proportion to the hard segment content.