Trimethylsilyl‐group containing polyphenylacetylenes for oxygen and ethanol permselective membranes

Abstract

Phenylacetylenes having one or two trimethylsilyl groups at their benzene ring were synthesized, and polymerized by [Rh(cyclooctadiene) (PPh3)2]PF6, [Rh(norbornadiene)Cl]2, or WCl6 to afford high molecular‐weight polymers in high yields. These poly(phenylacetylene)s were soluble in many kinds of solvents and were fabricated to tough membranes by the solvent casting method. The oxygen permselectivities of these membranes were very good. The oxygen permeability coefficients (Po2) and oxygen separation factors (α = Po2/PN2) of poly[2,4‐(o,p)‐bis(trimethylsilyl)phenylacetylene] [poly (o‐1‐p‐1)] and poly[(4(p)‐trimethylsilyl)phenylacetylene] [poly(p‐1)] membranes were 4.73 × 10−8 cc(STP) cm/cm2 s cmHg and 2.65, and 1.52 × 10−8 cc(STP) cm/cm2 s cmHg and 3.39, respectively. In the case of poly(o‐1‐p‐1), Po2 was comparable to that of polydimethylsiloxane (PDMS) and α was higher than that of PDMS. However, the Po2 value reduced to 48% of its initial value in about 1 year. In the case of poly(p‐1), the Po2 value did not change in about 1 year. Ethanol permeated preferentially through these membranes (αEtOH > 1) in pervaporation of aqueous ethanol solution, whereas poly(phenylacetylene) [poly(PhA)] showed water permselectivity (αEtOH < 1). These favorable effects of trimethylsilyl groups on the oxygen and ethanol permselectivities were discussed on the basis of comparison with those of poly(PhA), other poly(substituted phenyl‐acetylene)s, and trimethylsilyl‐group containing polystyrenes. © 1994 John Wiley & Sons, Inc.

New Macromolecular Architectures for Permselective Membranes—Gas Permselective Membranes from Dendrimers and Enantioselectively Permeable Membranes from One-handed Helical Polymers—

“…2,7,10,13,14,17 The zero generation poly(phenylacetylene) derivatives showed a trade off line between P O 2 and . However, the P O 2 values of the polydendrons with trimethylsilyl group, poly(TMS1H), poly-(TMS1PEH) and poly(TMSTPA1), showed good performance in comparison with the corresponding zero generation of poly(phenylacetylene) derivatives.…”

Poly(diphenylacetylene)s with Electron‐Donating Alkoxy and Electron‐Withdrawing Fluoroalkyl Groups: Effect of the Substituent on Fluorescence

“…[29,30] All of the reactions proceeded smoothly, and the monomers were obtained in high yields. Table 1 Table 1, the TaCl 5 -n-Bu 4 Sn catalyst provided no polymeric product for monomers 1 0 , 2 0 and 4 0 .…”

“…It was then flushed with dry nitrogen. Triethylamine (300 mL), (Ph 3 P) 2 PdCl 2 (0.225 g, 0.32 mmol), CuI (0.386 g, 1.98 mmol), Ph 3 P (0.353 g, 1.344 mmol), and (4-trimethylsilyl)phenylacetylene [30] (5.57 g, 0.032 mol) were placed in the flask. The mixture was then stirred for 1 h. 4-Bromobenzotrifluoride (7.2 g, 0.032 mol) in triethylamine (50 mL) was then added drop-wise, and stirring was continued for an additional 12 h. Then triethylamine was evaporated.…”

Synthesis, Characterization and Optical Properties of a Novel Si-Containing σ-π-Conjugated Hyperbranched Polymer

“…The NMR signals of hyperbranched polymers can be assigned by the use of model compounds that possess structures close to the terminal, semidendritic, and dendritic units in the polymers. It has been known that the proton signal of Si(CH 3 ) 3 (0.26 ppm in CDCl 3 ) of (4-trimethylsilyl)phenylacetylene [17] shows a downfield shift compared to that (0.23 ppm in CDCl 3 ) of (4-trimethylsilyl)styrene. [18] Hence the three peaks t, s and d of poly (1) can be assigned to the three silicon environments (terminal, semidendritic, dendritic), respectively, as shown in Figure 2 b.…”