Rigid foam and associated article and method

Abstract

A rigid polyurethane or polyisocyanurate foam includes 1 to 50 weight percent of a particulate poly(phenylene ether) having a mean particle size of 1 to 40 micrometers. The particulate poly(phenylene ether) imparts reduced flammability and reduced water absorption to the foam. The foam is useful as a thermally insulating material in articles including domestic appliances, building materials, tanks, pipelines, heating pipes, cooling pipes, cold stores, and refrigerated vehicles.

Description

BACKGROUND OF THE INVENTION[0001]Polyurethanes are prepared from compounds with at least two hydroxyl groups and compounds with at least two isocyanate groups. See, e.g., D. Randall and S. Lee, “The Polyurethanes Book”, New York: John Wiley & Sons, 2003; and K. Uhlig, “Discovering Polyurethanes”, New York: Hanser Gardner, 1999. The isocyanate groups of the isocyanate compound react with the hydroxyl groups of the hydroxyl compound to form urethane linkages. In many cases, the hydroxyl compound is a low molecular weight polyether or polyester. The isocyanate compound can be aliphatic or aromatic, and in the preparation of linear polyurethanes is typically difunctional (i.e., it is a diisocyanate). However isocyanate compounds with greater functionality are used in preparing thermoset polyurethanes. The family of polyurethane resins is very complex because of the enormous variation in the compositional features of the hydroxyl compounds and isocyanate compounds. This variety results i...

AI Technical Summary

Benefits of technology

This patent describes a new type of foam made from polyurethane or polyisocyanurate that contains small polymer particles made of poly(phenylene ether). These particles help improve the foam's thermal insulation. The resulting foam has a core density of 0.03 to 0.7 grams per cubic centimeter at 23°C and is suitable for use as thermal insulation. The use of these particles allows for a more uniform cell structure and better insulation properties. The method of making this foam involves reacting a polyol and an isocyanate compound in the presence of a blowing agent and the particulate poly(phenylene ether) particles. The resulting foam has improved properties and can be used in a variety of applications such as thermal insulation.

Problems solved by technology

The family of polyurethane resins is very complex because of the enormous variation in the compositional features of the hydroxyl compounds and isocyanate compounds.

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