English Abstract

Science and Technology of Polyurethanes was the Polyurethane Understood in How Far?
V Source of Rubber Elasticity

Mutsuhisa FURUKAWA
The Emeritus Professor of Nagasaki University, Institute of Nagasaki Polyurethane Science and Technology, Chuo-ku, Fukuoka, Japan
Nippon Gomu Kyokaishi,(2019),92(5),182-187 General Review in Japanese

Polyurethane elastomers (PUEs) are one of the most popular polar polymers. The PUEs are usually composed of soft segment formed with polymer glycol and hard segment done with diisocyanate and curing agent. The properties of the PUEs are strongly dependent on chemical structure, molecular weight and polydispersity of soft segment or hard segment components, weight fraction of both components and so on. However, the quantitative contribution of physical cross linkages to rubber elasticity and the direct observation of micro phase separation have not been done yet. The molecular design factors for high performance PUEs and origin of rubber elasticity are discussed by chemical analysis of crosslinks and observation of the micro phase-separated structure of the PUEs using AFM.

Keywords: Concenration of Network Chains, Chemical Crosslinking, Physical Crosslinking, Mirco-chohesive Structure