通过反应挤出对聚碳酸酯进行扩链

Chain extension of polycarbonate through reactive extrusion

采用反应挤出机(缩聚型)研究了聚碳酸酯(PC)在熔融挤出过程中在各种添加剂作用下的扩链反应。结果表明:降低螺杆转速和提高挤出机反应段的温度有利于提高产物的特性黏数([η]);加入均苯四甲酸二酐、双(?)唑啉、苯乙烯-马来酸酐共聚物、无机氧化物、钛酸四丁酯等对产物的[η]提高不大;加入过氧化物对PC的扩链有一定的作用;加入高黏型的聚对苯二甲酸丁二酯(PBT)使产物的[η]显著提高,w(PBT)为50%时,由纯PC的0.361 dL/g提高至0.695 dL/g。

Chain extension of polycarbonate（PC） under the functions of several kinds of additives in the reactive extrusion process was studied. The results show that reducing screw rotation speed or raising reactive temperature is favorable to increasing intrinsic viscosity（[η]） of PC extrudates. Adding pyromellitic dianhydride, bis（oxazolines）, styrene-maleic anhydride copolymer, inorganic oxide or tetrabutyl titanate makes [η] of the resultant product augment a little. Peroxide benefits chain extension of PC to some extent. The [η] of the product increases significantly when polybutylene terephthalate（PBT） with high viscosity is added into PC; the [η] rises to 0.695 dL/g from 0.361 dL/g of pure PC when PBT mass fraction reaches 50%.