Manufacture of polyurethane

Abstract

Abstract PURPOSE:To obtain a polyurethane of high low-temperature flexilibity and outstanding resistance to hydrolysis, heat and photooxidative deterioration, useful for casting-type elastomer etc., by the reaction between polyisocyanate and polycarbonate polyol having in its molecule a specific group. CONSTITUTION:The objective polyurethane can be obtained by the reaction between (A) a polycarbonate polyol having in its molecule group of formula: -O(CH2)2C(CH3)H(CH2)2O-, (B) a polyisocyanate, pref. 4,4'-diphenylmethane diisocyanate, and, if necessary, (C) a chain extender having at least two active hyrogen atoms reactive with the component (B) (e.g., 1,4-butanediol). The component (A) can be synthesized from (1) pref. 50-100wt% of 3-methyl-1,5-pentanediol and (2) 1,6-hexanediol, etc.; however, in case of trying to improve the resistance to heat and photooxidative deterioration of the final polyurethane, >=50wt% of 1,6-hexanediol shall preferably be used.

Inventors

• 👤 Koji Hirai
• 👤 広治 平井
• 👤 Michihiro Ishiguro
• 👤 通裕 石黒
• 👤 Takayuki Okamura
• 👤 岡村　高幸

Bibliographic Details