Synthesis, chiroptical properties, and high gas permeability of poly(phenylacetylene) with bulky chiral silyl groups

(+)-p{[Methyl(1-naphthyl)phenyl]silyl} phenylacetylene was polymerized with transition-metal catalysts, and the thermal properties, circular dichroism effects and oxygen permeability of the resulting polymers were examined. The structure and properties of the polymer were examined using mainly the Rh-based sample. The infrared spectrum of the polymer did not exhibit the absorption observed in the monomer at 3283 cm^-1. However, the ultraviolet-visible (UV-vis) spectrum of the polymer showed two absorption maxima at 334 and 420 nm, and virtually no absorption above 490 nm. On the other hand, the UV-vis spectra of the W-based polymer showed no absorption maximum and the cutoff wavelengths of their absorption were longer.