Patent · US Expired

Production of closed-cell polyurethane moldings having a densified surface zone

US4436869A · kind A · utility

7Cited by

2References

7Claims

0Family size

Assignee

Elastogran GmbH · DE

Inventors

Otmar Zipp · Osnabrück, DE
Heinz Bollmann · Alfhausen, DE
Herbert Stutz · Karlsruhe, DE
Wolfgang Scholz · Beverly, US

Key dates

Filing date	Mar 30, 1982
Grant date	Mar 13, 1984
Priority date	—
Expiry date	Mar 30, 2002

Classification

Technology area (CPC C)Chemistry; Metallurgy
CPC primaryC08J2375/06
WIPO fieldMacromolecular chemistry, polymers
WIPO sectorChemistry

Abstract

A process for the preparation of moldings, in particular resilient elements, which by virtue of a densified surface zone with substantially closed cells, have only a low water absorption, wherein a mixture comprising: PA0 (a) 100 parts by weight of an NCO-containing prepolymer, having an NCO content of from 3 to 6% by weight and based on organic diisocyanates and substantially linear polyester-polyols or polytetramethylene ether glycol, PA0 (b) from 0.5 to 1.6 parts by weight of water, PA0 (c) one or more catalysts, preferably a tertiary amine, in an amount of from 0.01 to 2.0 parts by weight and PA0 (d) assistants, with or without additives, is reacted in a closed mold, while undergoing densification, the surface temperature of the inner wall of the mold being from 50.degree. to 70.degree. C.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.