T. Aoki et al., TRIMETHYLSILYL-GROUP CONTAINING POLYPHENYLACETYLENES FOR OXYGEN AND ETHANOL PERMSELECTIVE MEMBRANES, Journal of polymer science. Part A, Polymer chemistry, 32(5), 1994, pp. 849-858
Phenylacetylenes having one or two trimethylsilyl groups at their benz
ene ring were synthesized, and polymerized by [Rh (cyclooctadiene) (PP
h3)2]PF6, [Rh(norbornadiene) Cl]2, or WCl6 to afford high molecular-we
ight polymers in high yields. These poly(phenylacetylene)s were solubl
e in many kinds of solvents and were fabricated to tough membranes by
the solvent casting method. The oxygen permselectivities of these memb
ranes were very good. The oxygen permeability coefficients (P(O2)) and
oxygen separation factors (alpha = P(O2)/P(Na)) of poly[2,4(op)-bis(t
rimethylsilyl)phenylacetylene] [poly(o-1-p-1)] and y[(4(p)-trimethylsi
lyl)phenylacetylene][poly(p-1)] membranes were 4.73 X 10(-8) cc (STP)
cm/cm2 s cmHg and 2.65, and 1.52 X 10(-8) cc (STP) cm/cm2 s cmHg and 3
.39, respectively. In the case of poly(o-1-p-1), P(O2) was comparable
to that of polymethylsiloxane (PDMS) and alpha was higher than that of
PDMS. However, the P(O2) value reduced to 48% of its initial value in
about 1 year. In the case of poly (p-1), the P(O2) value did not chan
ge in about 1 year. Ethanol permeated preferentially through these mem
branes (alpha(EtOH) > 1) in pervaporation of aqueous ethanol solution,
whereas poly(phenylacetylene) [poly(PhA)] showed water permselectivit
y (alpha(EtOH) < 1). These favorable effects of trimethylsilyl groups
on the oxygen and ethanol permselectivities were discussed on the basi
s of comparison with those of poly (PhA), other poly (substituted phen
yl-acetylene) s, and trimethylsilyl-group containing polystyrenes. (C)
1994 John Wiley & Sons, Inc.