Process for preparing highly reactive (semi)crystalline and amorphous blocked polyisocyanates

US6448363B1 · kind B1 · utility

Assignee

• Degussa AG · DE

Inventors

• Andreas Wenning · Nottuln, DE
• Thomas Weihrauch · Schneverdingen, DE

Key dates

• Filing date: Jul 6, 2001
• Grant date: Sep 10, 2002
• Expiry date: Jul 6, 2021

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08G2150/20
• WIPO field: Macromolecular chemistry, polymers
• WIPO sector: Chemistry

Abstract

The present invention provides a solventless, continuous process, which includes:in at least one extruder, intensive compounder, intensive mixer or static mixer,mixing and heating a reaction mixture including the following (A), (B), and one or both of (C) and (D):(A) at least one aliphatic, (cyclo)aliphatic and/or cycloaliphatic C3-C50 diisocyanate compound;(B) at least one aliphatic, (cyclo)aliphatic and/or cycloaliphatic C3-C50 polyisocyanate compound containing one or more isocyanurate groups;(C) 1,2,4-triazole;(D) one or more pyrazole having the formula: where R1, R2 and R3 simultaneously or independently of one another are hydrogen or alkyl, alkenyl, aralkyl, aryl or N-substituted carbamoyl groups, halogen or —C(═O)—O—R4, where R4 is a C1-C12 alkyl group;to obtain a product mixture including at least one (semi)crystalline, blocked C3-C50 isocyanate compound and at least one amorphous, blocked C3-C50 isocyanate compound. The present invention also provides a composition prepared by the process and methods of using the composition.