Synthesis and gas permeation properties of various Si-containing poly(diarylacetylene)s and their desilylated membranes

✍ Scribed by Yanming Hu; Kyohei Hattori; Akito Fukui; Masashi Shiotsuki; Fumio Sanda; Toshio Masuda

• Publisher: Elsevier Science
• Year: 2010
• Tongue: English
• Weight: 587 KB
• Volume: 51
• Category: Article
• ISSN: 0032-3861
• DOI: 10.1016/j.polymer.2010.02.015

✦ Synopsis

Diarylacetylene monomers having trimethylsilyl groups and other substituents (substituted biphenyl, 1a and 1b; trimethylsilylmethylphenyl, 1cee) were synthesized and polymerized with TaCl 5 -n-Bu 4 Sn catalyst to produce the corresponding poly(diarylacetylene)s (2aed). Polymers 2aec had high molecular weights and were soluble in common organic solvents. Free-standing membranes of 2aec as well as previously reported 2feh were prepared by the solution-casting method. Desilylation of these Si-containing polymer membranes was carried out with trifluoroacetic acid to afford 3a, 3b, and 3feh. Upon desilylation, biphenyl-containing membranes became less permeable (3a, b), whereas fluorene-containing membranes became more permeable (3feh). In particular, 3h exhibited extremely high gas permeability (PO 2 ¼ 9800 barrers), which is about the same as that of poly(1-trimethylsilyl-1-propyne). Desilylated membranes 3a and 3feh showed different gas permeability from that of polymers 2iek which have the identical chemical structures and obtained directly by the polymerization of the corresponding monomers.