Gas sorption in substituted polyacetylenes

Sorption of several gases (He, N-2, Ar, CH4, CO2, C2H6) was measured in an extended pressure range (up to 100 at m) in two glassy polyacetylenes: poly[1-phenyl-2-(p-tert-butylphenyl)acetylene] and samples of poly[1-(trimethylsilyl)-1-propyne] (PTMSP), which were partly oxidized during long term storage in the ambient atmosphere. Sorption isotherms are concave to the pressure axis and can be described by the dual mode sorption model. Both polyacetylenes are distinguished by relatively large Langmuir sorption capacity parameters C-H'. However, the C-H' values and solubility coefficients are significantly lower than these of fresh PTMSP.