High‐Tg Transparent Poly(ether sulfone)s Based on Phosphinated Bisphenols

Abstract The preparation of high‐ T g transparent polymers from poly(ether sulfone)s with bulky phosphinate pendants is described. Poly(ether sulfone)s P1–P3 based on biphenylene phosphinate‐substituted bisphenols were prepared. The thermal properties of P1 and P2 were studied and compared with a bisphenol‐A‐based poly(ether sulfone) . P1 and P2 are flexible, foldable, and highly transparent with a cutoff wavelength around 327 and 328 nm, respectively. They display higher glass transition temperature (258 and 274 °C) and lower coefficient of thermal expansion ( δ = 48 ppm per °C by TMA) than those of P0 (208 °C and δ = 57 ppm per °C). magnified image