| Polyarylates, also called as aromatic polyesters, are the special engineering plastics with ester bonds and aromatic rings in main chains. Due to their excellent properties such as good transparent capability, high surface rigidity, unique ultraviolet resistance, heat-resistance and fireproof, polyarylates were developed rapidly and employed widely in recent years. However, polyarylates synthesized from bisphenol-A with only terephthaloyl chloride (TPC) or isophthaloyl chloride (IPC) or the mixture of the two compounds are of higher glass transition temperature and are more brittle, so they are inconvenient to be processed and applied.In this research work, bis [(4-chlorocarbonyl)phenyl]dimethyl silane (DMS),a new monomer was synthesized and characterized with FTIR and NMR. To carry out this research work, a series of polyarylates without silicon were synthesized on which the effect of the amount of alkali, phase transfer catalyst, the proportion of TPC or IPC to polymerization were studied. The above experimental factors in properties of polyarylates of high molecular weight were also determined.Two ways were used to improve the properties of silicon-containing polyarylates: 1) DMS was used as substitute for terepththaloyl chloride; 2) DMS was substituted for isophthaloyl chloride with the adding rate of 5% every time while keeping the content of terepththaloyl chloride at 30%. A series of polyarylates were synthesized in those ways and characterized with FTIR, 1HNMR, UV, DSC, and TG et al. The polyarylates synthesized in the second way seem to have lower glass transition temperature and excellent processing properties of polyarylates at lower temperature. Solubility tests show that the polyarylates synthesized in the second way have better dissolvability in common solvents.Maintaining the outstanding advantages of conventional polyarylates, silicon-containing polyarylates are improved in the processing properties of polyarylateds, which lead them to a wider field of application.
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