Study On Synthesis And Properties Of High Molecular Weight Bisphenol-A Polyarylester

Polyarylates have been known as one of the high performance thermoplastic polymers and were widely used in the high-tech and domestic industry areas for their good transparent capability, ultraviolet shielding, low flammability, excellent tear strength and the dart impact intensity, surface hardness and creep resistant.This dissertation contains three parts:High molecular weight bisphenol-A polyarylesters were synthesized by interfacial polycondensation, for tereptllthaloyl chloride (TPC) and dimepththaloyl chloride (IPC) and bisphenol-A (BPA) as monomers, in the presence of a phase transfer catalyst. The structure of copolymers was characterized by Fourier infrared absorb spectrum (FT-IR) and 1H NMR. Thermal properties were carried by differential scanning calorimetry (DSC) and thermogravimetry (TG).The affect of polymerization temperature, amount of catalyst, solvent and the ratio of monomers on polycondensation were investigated. The result showed that inherent viscosity of the polyarylesters was at the range of 2.0 to 3.6 dL/g. The optimized polymerization conditions were testified at the presence of dichloromethane as organic solvent, 3-ethyl benzyl ammonium chloride(BTEAC) for phase transfer catalyst and 4,4'-diahydroxydiophenyl propane monomer concentration of 0.147g/mol. Simple synthesis processing, moderate condition and the solvent can be recycled by dehydrated distillation so it was a sufficient strategy for the industrial production of bisphenol-A polyarylesters.Random polyarylestes with isophthalate moieties were synthesized by interfacial polycondensation with tereptllthaloyl chloride (TPC), dimepththaloyl chloride (IPC) and bisphenol-A (BPA). Random copolymers were characterized by DSC, TG and mechanical tested modern advanced analyst. The result of DSC indicated that copolymers had high glass transition temperature (Tg) and at the range of 194.5℃to 240.1℃. The copolymers also showed a high thermal stability with 5% weight-loss temperature beyond 432℃in nitrogen atmosphere according to thermogravimetric analysis (TG). It was indicated that the softening temperature and the glass transition temperature (Tg) decreased with increasing the amount of isophthalate moieties in the main chain, while the thermal decomposition temperature (Td) affected slightly. Mechanical properties, tensile strength, elongation at break and Young's module of copolymers were also tested. WAXD showed that copolymers converted into amorphous when increasing the amount of isophthalate moieties in the main chain. Therefore we can prepare a serials of different thermal stability PAR production by adjust the mol ration of TPC and IPC.Epoxy-terminated polyarylesters were also prepared by epoxidation reaction of the chloro-hydro-terminated polyarylesters at the presence of sodium hydroxide. The functional polyarylesters synthesized by bisphenol-A and isophthaloyl chloride, which quenched by excess of 3-chloroprolene oxide. The epoxy-modified polyarylesters were characterized by FT-IR and 1H-NMR, and the content of end epoxy groups was determined by argentimetric method. Epoxy-terminated polyarylesters could be formed by the common solidification agents. It provides a sound basis for development a serial of thermal stability polyarylesters and exploring their applications.