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:
Nov. 14, 1989
Filed:
Jan. 12, 1989
Robert E Kesting, Elsenfeld, DE;
Alfred K Fritzsche, Manchester, MO (US);
Milton K Murphy, Clayton, MO (US);
Alan C Handerman, Matthews, NC (US);
Clint A Cruse, St. John, MO (US);
Raymond F Malon, Edmundson, MO (US);
Permea, Inc., St. Louis, MO (US);
Abstract
Asymmetric gas separation membranes having graded density skins and macrovoid-free morphology comprised of glassy, hydrophobic polymers are disclosed which are effective for separation gases with significante increases in permeation while maintaining equal or greater separation electivity. The membranes have increased free volume and the graded density skin exhibits a density gradient which becomes more dense with increasing proximity to the surface, the membrane effectively decouples the interdependency between permeability and separation selectivity.