Gas permeability of polyacetylenes carrying substituents

Abstract

AbstractThe gas permeabilities of three polyacetylene films, prepared from poly[1‐(trimethylsilyl)‐1‐propyne], poly(tert‐butylacetylene), and poly(1‐chloro‐2‐phenylacetylene), were studied. Although depending on conditions of polymerization and membrane preparation, typical permeability coefficients P of the polymers to oxygen and nitrogen at 25°C were as follows: poly[1‐(trimethylsilyl)‐1‐propyne], PO2 = 40 × 10−8, PNr2 = 20 × 10−8; poly(tert‐butylacetylene), PO2 = 3.0 × 10−8, PN2 = 1.0 × 10−8; poly(1‐chloro‐2‐phenylacetylene), PO2 = 9.4 × 10−10, PN2 = 2.0 × 10−10 cm3(STP) · cm/(cm2 · s · cm Hg). Thus PO2 of a poly[1‐(trimethylsilyl)‐1‐propyne] film is the largest among those ever known, and the values of poly(tert‐butylacetylene) and poly(1‐chloro‐2‐phenylacetylene) films are also fairly large. Influences of polymer structure, measuring temperature, and so forth on the PO2 and PN2 of these polyacetylene films were studied. The possibility of applying these films to oxygen enrichment of air are being discussed.