Process for the production of prepolymers containing isocyanate groups, prepolymers produced by this process and their use

US4777220A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Reinhard Halpaap · Odenthal, DE
• Manfred Bock · Leverkusen, DE
• Josef Pedain · Cologne, DE
• Gerhard Klein · Monheim, DE
• Dieter Arlt · Cologne, DE

Key dates

• Filing date: Feb 3, 1988
• Grant date: Oct 11, 1988
• Expiry date: Feb 3, 2008

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/735
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention is directed to a process for the production of prepolymers containing free tertiary isocyanate groups by reacting PA1 (a) an organic diisocyanate containing one isocyanate group attached to a primary aliphatic carbon atom and an isocyanate group attached to a tertiary aliphatic or cycloaliphatic carbon atom with PA1 (b) a polyester polyol having a molecular weight of 800 to 12,000 and a hydroxyl functionality of 2 to 6 at an NCO/OH equivalent ratio of 1.6:1 to 2:1 to provide prepolymers having a molecular weight of about 1000 to 3000 and an NCO content of about 4 to 12%. The present invention is also directed to the prepolymers containing free isocyanate groups obtained by this process and to their use for the production of polyurethane lacquers and coatings.