Structure and Properties of the Mesophase of Syndiotactic Polystyrene IV. Release of Guest Molecules from δ Form of Syndiotactic Polystyrene by Time Resolved FT-IR and WAXD Measurement

Abstract

Syndiotactic polystyrene(sPS) forms clathrates with organic solvent molecules between helical chains of trans–trans–gauche–gauche(TTGG) conformation, so called δ form complex. By annealing or extraction, the δ form transforms to the mesophase which has highly regulated molecular cavities between helical chains. Time resolved FT-IR spectra of the sPS films containing δ form complex with toluene were obtained to clarify the relationship between the release of toluene from the δ form and conformational changes of sPS backbone chain. From the results of FT-IR, content of TTGG conformation decreased with annealing time, and increased with extraction time by acetone, indicative of the formation of γ form from amorphous phase. The mesophase extracted holds high content of TTGG conformation and is stable, compared to annealed sample. The solvent extraction method is thus a better technique to make mesophase membranes containing molecular cavities.