Method for the preparation of polyurethane foams

US5082868A · kind A · utility

Assignee

• Th. Goldschmidt. AG · DE

Inventors

• Georg Burkhart · Essen, DE
• Jurgen Fock · Goldkronach, DE
• Volker Mohring · Neheim, DE

Key dates

• Filing date: Jul 21, 1989
• Grant date: Jan 21, 1992
• Expiry date: Jul 21, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C08J2457/00
• WIPO field: Other special machines
• WIPO sector: Mechanical engineering

Abstract

A method for the preparation of rigid polyurethane and/or polyisocyanurate foams is disclosed. The foams are produced by the reaction of at least difunctional polyisocyanates, a polyol with 3 to 8 hydroxyl groups, said polyol having a hydroxyl number of about 150 to 800, catalysts, blowing agents and foam stabilizers, which are devoid of silicon atoms, as well as, optionally, conventional additives such as flame retardants and chain extenders. The foam stabilizers are copolymers of vinyl monomers and allyl- or methallyl polyoxalkylene ethers. The mole ratio of the monomers is 1:1 to 10:1. The foams thus produced exhibit an improved burning behavior, good surface properties and outstanding thermal insulation effects. The stabilizers increase the solubility of the halocarbon blowing agents in the foaming formulation.