The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 10, 1990
Filed:
Nov. 28, 1989
Jeffrey A Kuphal, Blandon, PA (US);
Lloyd M Robeson, Macungie, PA (US);
Joseph G Santangelo, Allentown, PA (US);
Air Products and Chemicals, Inc., Allentown, PA (US);
Abstract
A process for producing cellular foamed articles from high temperature engineering polymers wherein polymeric blowing agents are utilized to expand the polymers. The process comprises mixing a first polymer capable of being foamed with a second polymer comprising at least one poly(alkylene carbonate) to provide a polymer blend; heating the polymer blend to a temperature sufficient to melt the polymer to be foamed and to decompose the second polymer to form gas inclusions within the first polymer; expanding the melted first polymer containing the gas inclusions to form a foamed article; and cooling the foamed article to a temperature below the melting or softening point of the foamed article. Polymers which may be foamed according to the process include those polymers which can tolerate processing temperatures in excess of 260.degree. C. Suitable poly(alkylene carbonate) foaming agents include poly(propylene carbonate), blends of two or more poly(alkylene carbonates) and copolymers and terpolymers formed by polymerizing two or more oxirane compounds in the presence of carbon dioxide.