Polymer characterization and gas permeability of poly(1-trimethylsilyl-1-propyne) [PTMSP], poly(1-phenyl-1-propyne) [PPP], and PTMSP/PPP blends

✍ Scribed by A. Morisato; H. C. Shen; S. S. Sankar; B. D. Freeman; I. Pinnau; C. G. Casillas

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 908 KB
• Volume: 34
• Category: Article
• ISSN: 0887-6266
• DOI: 10.1002/(sici)1099-0488(19960930)34:13<2209::aid-polb10>3.0.co;2-9

✦ Synopsis

Pure gas and hydrocarbon vapor transport properties of blends of two glassy, polyacetylene-based polymers, poly( 1-trimethylsilyl-1-propyne) [PTMSP] and poly( l-phenyl-lpropyne) [ PPP], have been determined. Solid-state CP/MAS NMR proton rotating frame relaxation times were determined in the pure polymers and the blends. NMR studies show that P T M S P and PPP form strongly phase-separated blends. The permeabilities of the pure polymers and each blend were determined with hydrogen, nitrogen, oxygen, carbon dioxide, and n-butane. PTMSP exhibits unusual gas and vapor transport properties which result from its extremely high free volume. P T M S P is more permeable to large organic vapors, such as n-butane, than to small, permanent gases, such as hydrogen. PPP exhibits gas permeation characteristics of conventional low free volume glassy polymers; PPP is more permeable to hydrogen than to n-butane. In P T M S P / P P P blends, both nbutane permeability and n-butanelhydrogen selectivity increase as the P T M S P content of the blends increases. 0