Modified polysulfones 5: Synthesis and characterization of tetramethyl polysulfones containing trimethylsilyl groups and their gas transport properties

被引:25
作者
Dai, Y
Guiver, MD
Robertson, GP
Bilodeau, F
Kang, YS
Lee, KJ
Jho, JY
Won, J
机构
[1] Natl Res Council Canada, Inst Chem Proc & Environm Technol, Ottawa, ON K1A 0R6, Canada
[2] Korea Inst Sci & Technol, Ctr Facilitated Transport Membranes, Seoul 130650, South Korea
[3] Korea Inst Sci & Technol, Polymer Phys Lab, Seoul 130650, South Korea
[4] Seoul Natl Univ, Hyperstructed Organ Mat Res Ctr, Seoul 151744, South Korea
[5] Seoul Natl Univ, Sch Chem Engn, Seoul 151744, South Korea
[6] Sejong Univ, Dept Appl Chem, Seoul 143747, South Korea
关键词
polysulfone modification; trimethylsilyl; gas transport;
D O I
10.1016/S0032-3861(02)00411-1
中图分类号
O63 [高分子化学(高聚物)];
学科分类号
070305 ; 080501 ; 081704 ;
摘要
Polysulfones with rigid backbone structures and silyl-containing substituents were prepared as membrane materials with potentially enhanced gas transport properties. Tetramethylbisphenol-A polysulfone (TMPSf) and tetramethylbiphenol polysulfone (TMPPSf) were made by polycondensation then post-modified to introduce trimethylsilyl (TMS) groups by bromination and lithiation methodology. Substitution of high levels of TMS groups at the ortho-sulfone sites was achieved using direct lithiation followed by addition of a trimethylsilane electrophile. In an approach to increase the overall TMS substitution level as well as introduce these groups on the bisphenol segment, both TMPSf and TMPPSf were cleanly brominated to a degree of substitution (DS) of 2.0 for bromine. While the subsequent lithium-halogen exchange and reaction with TMS electrophile did not give high regioselectivity because of steric hindrance, the overall DS of TMS in the polymers was increased when excess n-butyllithium was used to activate both brominated and ortho-sulfone sites. The polymer structures were characterized by NMR spectroscopy. Their thermal properties as well as O-2, N-2, CO2 and CH4 gas transport properties were measured. Polymers with a high DS of TMS had very high CO2 and O-2 permeabilities and good permselectivities from N-2. The permselectivities of CO2/N-2 were at or close to the Robeson upper-bound performance line. (C) 2002 Published by Elsevier Science Ltd.
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页码:5369 / 5378
页数:10
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