熔融酯交换法原位合成炭黑/聚碳酸酯导电复合材料

利用原位聚合法合成具有导电性能的炭黑(CB)/聚碳酸酯(PC)复合材料。在聚合反应过程中, CB与PC在较低黏度下更好地混融, 而且通过负载催化剂连接CB和PC分子, 使CB参与PC链增长过程, 从而使CB有效分散。与传统的熔融共混法相比, 利用原位聚合法制备的CB/PC导电复合材料的渗滤阈值低, 当复合材料的体积电阻率为1.56×10⁶ Ω·mm时, CB的质量分数仅为4.32%。通过SEM观察发现, 原位法得到的样品中CB与PC充分混融, 形成导电网络更充分有效。利用原位聚合法得到的样品的正温度系数(PTC)的对数值达到4.69, 具有作为自控温材料的潜力。

In-situ synthesis of carbon black/polycarbonate conductive composites by melt-transesterification process

Carbon black (CB)/polycarbonate (PC) conductive composites was synthesized by in-situ polymerization method, during which CB could be dispersed more easily and more uniformly in PC with lower viscosity. Moreover, the catalyst loaded on CB also plays the role of the coupling agent to help CB better dispersing. Compared with the conventional melt blending method, CB/PC conductive composites synthesized by in-situ polymerization method have lower percolation threshold, and the volume resistivity of the composite with 4.32% mass fraction of CB is 1.56×10⁶ Ω·mm. SEM shows that CB in the samples synthesized by in-situ method is mixed more completely, and forms conductive network more effectively.The logarithm of the positive temperature coefficient (PTC) of the CB/PC sample obtained by in-situ method is 4.69. CB/PC conductive composites have the potential as self-temperature control material.