Multi-block polymer comprising a first amide acid prepolymer, chain extended with a compatible second prepolymer, the membrane made therefrom and its use in separations
US5130017A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 6, 1990 |
| Grant date | Jul 14, 1992 |
| Priority date | — |
| Expiry date | Dec 6, 2010 |
Classification
- Technology area (CPC C)Chemistry; Metallurgy
- CPC primaryC10G31/11
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
The present invention is directed to a multi-block polymeric material comprising a first amide acid prepolymer, made by combining (A) a diamine with (B) a dianhydride or its corresponding tetraacid or diacid-diester in an A/B mole ratio ranging from about 2.0 to 1.05, preferably about 2.0 to 1.1, chain extended with a second, different, compatible prepolymer selected from the group of prepolymers comprising (A) a dianhydride or its corresponding tetraacid or diacid-diester combined with a monomer selected from (B) epoxy, diisocyanate and polyester in an A/B mole ratio ranging from about 2.0 to 1.05, preferably about 2.0 to 1.1. The present invention is also directed to membranes of the above recited multi-block polymeric materials, especially membranes comprising thin, dense films of said multi-block polymeric material deposited on a micro porous support layer producing a thin film composite membrane. The membranes of the multi-block polymeric material, especially the thin film composite membranes, are useful for separating aromatic hydrocarbons from mixtures of same with non-aromatic hydrocarbons under perstraction or pervaporation conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.