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:
Jun. 03, 1997
Filed:
Mar. 14, 1995
Applicant:
Inventor:
James T Macheras, Quincy, MA (US);
Assignee:
Praxair Technology, Inc., Danbury, CT (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B01D / ;
U.S. Cl.
CPC ...
21050023 ; 96-8 ; 21050039 ;
Abstract
Anisotropic fluid separation membranes having an integral discriminating layer are formed from blends of two types of polyimides. The first type is a phenylindane containing polyimide. The second type consists of polyimides formed from the reaction of benzophenone tetracarboxylic dianhydride (BTDA) and optionally pyromellitic dianhydride (PMDA), with toluene diisocyanate (TDI) and/or 4,4'-methylene-bis-phenylisocyanate (MDI). The ratio of Type 1 polymer to Type 2 polymer is 1 or less. The blend membranes are particularly useful for gas separation.