Patent · US Expired

Purification, impregnation and foaming of polymer particles with carbon dioxide

US5049328A · kind A · utility

69Cited by
9References
15Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 2, 1990
Grant dateSep 17, 1991
Priority date
Expiry dateJul 2, 2010

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S264/09
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

A process for making high-purity foam moldings without the use of organic blowing agents involves the use of inorganic gases such as carbon dioxide, nitrogen, air and other pneumatogens. The process involves the simultaneous impregnation and purification of the polymers with or without foaming. If foaming is not done in the extractor, the polymeric particles can be foamed in pre-expanders or expanded and molded in downstream equipment.

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