Enhancement of CO2 permeability of poly(vinyl ether)s having oxyethylene chains by the sequence control of crosslinking sites. Issue 23 (1st March 2017)

• Record Type: Journal Article
• Authors: Sakaguchi, T.; Yamazaki, S.; Hashimoto, T.
• Is Part Of: RSC advances. Volume 7:Issue 23(2017)
• Page Start: 13879
• Page End: 13885
• Publication Date: 2017-03-01
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/c7ra01353a
• Languages: English
• ISSNs: 2046-2069

Abstract

Abstract : Triblock copolymers exhibited high gas permeability than the random copolymers. The triblock copolymers have the crosslinking only at the end segments, which makes the polymer chains more flexible than the random copolymers. Abstract : Sequential living cationic copolymerizations of vinyl ethers having oxyethylene side chains (MOEO2 VE and MOEO3 VE) with vinyl ether having a crosslinkable group (VEEM) provided the ABA-typed triblock copolymers poly(VEEM)- b -poly(MOEO2 VE)- b -poly(VEEM)s and poly(VEEM)- b -poly(MOEO3 VE)- b -poly(VEEM)s. All triblock copolymers are sticky liquids at room temperature, and the T g s were −77 to −73 °C. Heating the triblock copolymers afforded membranes by thermal crosslinking via mathacrylate groups at the outer segments in the polymers. All the membranes showed high CO2 permselectivity ( P CO2 / P N2 = 40–51) due to the high CO2 solubility selectivity ( S CO2 / S N2 = 44–61). The CO2 permeability of the triblock copolymers was higher than that of the random copolymers with the same composition ratios. This indicates that the inner segment (MOEO2 VE and MOEO3 VE) effectively enhanced the gas diffusivity in the polymer matrix because the crosslinking points are present only in the outer segments.