肉厚PPDI系ポリウレタンエラストマーの熱劣化挙動

抄録

Thermal deterioration behaviors of the thick cylindrical polyurethanes were analyzed from the surface of samples to the inside. The polyurethanes were prepared from p-phenylene diisocyanate(PPDI), poly(hexamethylene carbonate) glycol(PHC), and chain-extenders which were 1, 4-butanediol (BD), 2, 2', 3, 3'-tetrachloro-4, 4'-diamino-diphenylmethane (TCDAM) and hydroquinone bis-2-hydroxyethyl ether(HQEE). Thermal deterioration behaviors of the polyurethanes aged at 150°C during 2 months were measured using Infra Red spectroscopy, dynamic viscoelastometer, DSC, and WAXS. While scission of allophanate crosslinkages and a little degree of micro-phase mixing occurred simultaneously in region of the surface of the samples, the micro-phase separation in the inside region was promoted by an annealing effect and reversible scission of allophanate crosslinkages. These behaviors depended on rigidity of hard segments.