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:
Dec. 29, 1981
Filed:
Apr. 24, 1981
Applicant:
Inventor:
Dennis A Knaus, Centerville, MA (US);
Assignee:
Packaging Industries Group, Inc., Hyannis, MA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C08J / ;
U.S. Cl.
CPC ...
521 79 ; 264 53 ; 264 54 ; 264D / ; 521 87 ; 521 88 ; 521 95 ; 521 98 ; 521189 ; 521910 ;
Abstract
A method for the preparation of polysulfone foam using methylene chloride as a blowing agent. A pressurized combination of heat-plastified foamable gel of polysulfone containing methylene chloride as a blowing agent is extruded into a zone of lower pressure through an orifice of a die. As the gel expands into a foam, it forms a product of decreased density, increased resiliency and flexibility, and improved insulation properties over conventional polysulfone foam.