Two kinds of aromatic dibenzoyl chloride monomer containing thioether unit 4,4′-Bis(4-chloroformylphenylthio)benzophenone (BP-DC) and 4,4′-thiodibenzoyl chloride (T-DC) were synthesized with two steps, which was reacted with diamine monomer containing thioether and amide unit to prepare a new kind of polyamide containing high quantity thio-ether group. The intrinsic viscosity of the polyamides was 0.76–0.90 dl/g obtained with optimum synthesis conditions. The polymers were found to have good optical properties: the optical transmittance of the aromatic polyamide film at 450 nm is higher than 80%, meantime the high quantity thio-ether unit provided the polymer with a high refractive index ranging from 1.691 to 1.696 and low birefringence of 0.007–0.008. At the same time the polymers had excellent thermal performance with glass transition temperature (Tg) of 226 °C–278 °C, initial degradation temperature (Td) of 427 °C–439 °C. They showed improved solubility in polar aprotic solvents.
Polyamide Refractive index Birefringence Heat-resistance Solubility
This is a preview of subscription content, log in to check access.
This work was supported by research grants from National High Technology Foundation of China (863 program, Grant No.: 2007AA03Z561).