Subnanoporous Highly Oxygen Permselective Membranes from Poly(conjugated hyperbranched macromonomer)s Synthesized by One-Pot Simultaneous Two-Mode Homopolymerization of 1,3-Bis(silyl)phenylacetylene Using a Single Rh Catalytic System: Control of Their Structures and Permselectivities

Abstract

Novel well-defined complex polymers, polymers of acetylene-type macromonomers having silylene–vinylene–phenylene–ethynylene hyperbranches, investigated as a new class of subnanoporous oxygen permselective membrane materials, were synthesized very easily by one-pot simultaneous two-mode homopolymerization of a single monomer with a single catalyst. For this “simultaneous polymerization” we synthesized AB2-type monomers (1,3-bis(dimethylsilyl)phenylacetylenes) containing one terminal triple bond and two Si–H groups. The resulting poly(hyperbranched macromonomer)s had high molecular weights, low densities, high solubility, and good self-membrane forming ability. They had higher oxygen permselectivities (α = PO2/PN2) than any other reported polymers having similar oxygen permeabilities (PO2). These excellent polymer membranes could be obtained only by the simultaneous polymerization. In the one-pot simultaneous polymerization, the two different modes of polymerizations, i.e., addition polymerization of the tr...