Process for the production of stabilized polyisocyanates of retarded reactivity and their use in the production of polyurethanes

US4546165A · kind A · utility

Assignee

• BAYER HEALTHCARE LLC · DE

Inventors

• Gerhard Grogler · Leverkusen, DE
• Heinrich Hess · Cologne, DE
• Richard Kopp · Cologne, DE

Key dates

• Filing date: Jan 24, 1985
• Grant date: Oct 8, 1985
• Expiry date: Jan 24, 2005

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G18/80
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention relates to a process for the production of solid polyisocyanates of retarded reactivity stabilized by surface modification by reacting solid, finely divided polyisocyanates, and particularly dimeric tolylene diisocyanate, dimeric diphenylmethane diisocyanate and 3,3'-diisocyanato-4,4'-dimethyl-N,N'-diphenyl urea, with acyclic, mono- or bicyclic compounds having an amidine or guanidine structure and which do not contain any hydrogen atoms reactive to isocyanates at room temperature in a quantity of from 0.1 to 25 equivalent percent of "amidine" or "guanidine" per isocyanate equivalent. The reaction may be carried out directly in a liquid medium selected from the group consisting of active hydrogen compounds, plasticizers, water, and solvents to form a suspension of polyadduct-coated, stabilized polyisocyanates in the liquid medium.