Process for preparing heat-resistant polyurethane elastomers having no secondary softening range

US4191818A · kind A · utility

Assignee

• BASF Wyandotte Corporation · US

Inventors

• Karl H. Illers · Otterstadt, DE
• Herbert Stutz · Karlsruhe, DE

Key dates

• Filing date: Jul 10, 1978
• Grant date: Mar 4, 1980
• Expiry date: Jul 10, 1998

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G2250/00
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Polyurethane elastomers of improved heat stability are made by a process in which a polyisocyanate is reacted with a polyol of high molecular weight with an OH:NCO ratio of 1:0.66 to 1:0.85, and the resulting adduct is later reacted with an excess of symmetrical diisocyanate and a diol as chain extender.