Polyurethane elastomers with reduced gas permeability

US5710233A · kind A · utility

Assignee

• Rhein Chemie Rheinau GmbH · DE

Inventors

• Walter Meckel · Neuss, DE
• Klaus Konig · Leverkusen, DE
• Hans-Dieter Thomas · Bensberg, DE

Key dates

• Filing date: Jan 6, 1997
• Grant date: Jan 20, 1998
• Expiry date: Jan 6, 2017

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/65
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

Polyurethane elastomers with reduced gas permeability are prepared by reaction of: PA1 a) diisocyanates, PA1 b) compounds with a molecular weight of 500 to 10,000 having at least two hydrogen atoms that are reactive towards isocyanates, PA1 c) compounds with a molecular weight of 61 to 499 having at least two hydrogen atoms that are reactive towards isocyanates, and optionally PA1 d) further auxiliaries and additives, PA1 characterized in that PA2 i) the ratio of the isocyanate groups in a) to the sum of the isocyanate-reactive groups in b) and c) is between 1:0.80 and 1:1.05 (isocyanate:isocyanate-reactive), and PA2 ii) the compound b) contains 3 to 15% by wt. of amide bonds ##STR1##