Synthesis and Characterization of Novel Copoly(aryl ether sulfone) Containing Phthalazinone and Biphenyl Moieties

A series of poly(ether sulfone)s copolymers (BP-COPPESs) based on phthalazinone and biphenyl moieties were synthesized by nucleophilic displacement reaction from 4-(4-hydroxyphenyl)-2,3-phthalazin- 1-one (DHPZ), biphenol (BP) and bis(4-chlorophenyl) sulfone (BCS). The experimental results indicated that the higher initial concentration of the polymerization reaction resulted in lower cyclics content and narrower molecular weight distribution of resultant copolymers. Moreover, the molecular weight decreased with increasing content of phthalazinone moiety of the main chain. These copolymers showed high glass transition temperatures (T-g values) together with superior thermal properties. These copolymers were soluble in various aprotic solvents and were amorphous as evidenced by wide-angle X-ray diffraction. The molecular weights of BP-COPPES64 (60% phthalazinone moiety) could be controlled by utilizing excess molar content of BCS monomer. The rheological property test of copolymers indicated that the torque values decreased with increasing biphenyl group and ether linkage content.