含S双酚A型聚碳酸酯的制备与研究

Study on Preparing Sulful-Containing Bisphenol A Polycarbonate

采用熔融酯交换法,以双酚S(BPS)及4,4′-二羟基二苯硫醚、双酚A(BPA)、碳酸二苯酯(DPC)为原料合成主链含S的聚碳酸酯(PC)。考察了碱金属的乙酸类化合物及有机胺类化合物的催化作用,结果显示,乙酸钠的催化效果较好,采用碳酸钠、甲醇钠、氢氧化钠为催化剂时,其催化效果与乙酸钠相差不大,催化剂与BPA反应生成的钠盐可能真正起催化作用,其中以碳酸钠为催化剂时所得PC的透明性最好。当BPS,BPA与DPC的物质的量之比为0.1∶0.9∶1.08时,得到数均分子量(Mn)为24 748、重均分子量(Mw)为50 033、多分散系数(PDI)为2.02的PC。随着BPS用量的增加,难以获得高分子量PC,进一步考察了4,4′-二羟基二苯硫醚对合成PC的影响,结果发现,与BPS相比,4,4′-二羟基二苯硫醚的反应活性较好,当其加入量较多甚至全部取代BPA时,仍能得到分子量较高的PC。

Sulfur-containing polycarbonate was synthesized by melt transesterification of bisphenol S （BPS）,4, 4′-dihydroxydiphenyl sulfide,bisphenol A（BPA） and diphenyl carbonate（DPC）. Different catalysts,i.e. alkali metal acetate compounds and organic amine compounds were mainly investigated,in which sodium acetate performed the best catalystic effect. Meanwhile,a series of other sodium salt,i.e. sodium carbonate,sodium methoxide and sodium hydroxide were also studied. The catalytic effect of these sodium salt were similar to sodium acetate,which might be attributed by the reason that a intermediate sodium salt formed by the reaction of catalyst with BPA played a real catalytic role in the reaction. Due to a better transparent properties performed when using sodium carbonate as catalyst,the process condition were investigated using sodium carbonate with the amount of substance ratio of BPS,BPA and DPC being 0.1∶0.9∶1.08,and the polycarbonate with number-average molecular weight （Mn） of 24 748,weight-average molecular weight （Mw） of 50 033,polydispersity （PDI） of 2.02 is obtained. Besides,when the content of BPS is increased,it is unavailable to get high molecular weight of PC,so 4,4′-dihydroxydiphenyl sulfide was explored in this melt transesterification copolymerization. Compared to BPS,4,4′-dihydroxydiphenyl sulfide displayes higher reactivity,a high molecular weight is also obtained when the addition amount is much more or competely replacing BPA.