Amorphous fluorinated copolymer gas separation membranes
US10596527B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 10, 2016 |
| Grant date | Mar 24, 2020 |
| Priority date | — |
| Expiry date | Aug 27, 2036 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01D2325/20
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
Membranes having a permselective active layer of a copolymerized perfluorinated monomer and an non-fluorinated alkylvinylester monomer demonstrate superior selective permeability performance for separating gas mixtures compared to membranes of exclusively perfluorinated polymers. Preferred active layer compositions are copolymers of perfluoro-2,2-dimethyl-1,3 dioxole (PDD) copolymerized with an alkylvinyl ester such as vinyl acetate, and vinyl pivalate, and with alkylvinyl esters that are substantially hydrolyzed to provide copolymerized vinyl alcohol functionality. The membranes can have a thin, high diffusion rate, “gutter layer” of a fluorinated polymer highly permeable to nitrogen positioned between the active layer and a porous support layer. A novel copolymer effective in selectively permeable membranes is a copolymer of PDD and an alkylvinyl ester compound having the formula H2C═CHOC(O)R1 in which R1 is a linear or branched alkyl group of from 2 to 5 carbon atoms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.