ISSN:
0887-624X
Keywords:
substituted polyacetylene
;
silicon-containing polymer
;
silylmethyl group
;
transition-metal catalyst
;
living polymerization
;
gas permeability
;
Chemistry
;
Polymer and Materials Science
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
Novel phenylacetylene (PA) monomers, which have o-silylmethyl groups of different bulkinesses, i.e., o-Me3SiCH2PA, o-Et3SiCH2PA, and o-t-BuMe2Si-CH2PA, polymerized with W and Mo catalysts in high yields. The MoCl5-Ph4Sn catalyst achieved the highest weight-average molecular weights (Mw 7 × 105 - 12 × 105), and the Mw increased as the ortho-substitutent became bulkier (e.g., Mw of o-t-BuMe2SiCH2PA: 12 × 105). These monomers polymerized in a living fashion by the MoOCl4-n-Bu4Sn-EtOH catalyst. The resulting polymers were soluble in common solvents such as toluene and chloroform. In the UV-visible spectra, a tendency was observed that absorption maxima shifted to longer wavelengths as the substituents became bulkier. Membranes of the polymers were fairly permeable to gases (e.g., oxygen permeability coefficients 30-80 barrers). Though o-(Me3Si)2CHPA also polymerized with W and Mo catalysts, the product polymer was partly insoluble in any solvent. © 1995 John Wiley & Sons, Inc.
Additional Material:
5 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/pola.1995.080330114
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