非线性结构单元及柔性间隔链对共聚酯液晶性能的影响

在含有非线性结构单元4,4′-二羟基二苯基矾(SDP)或4,4′-二羟基二苯基丙烷(BPA)和氯代对苯二酚(HQCL)的芳香聚酯中引入柔性间隔(n=4、6或10,简称G_(4_(?))、C_(6_(?))、C_(10_(?)),研究了它们对此类三元共聚酯液晶性的影响。用对数比浓粘度、DSC和热台偏光显微镜对共聚酯进行研究。结果表明,各个共聚酯液晶均具有向列型的织态结构;引入柔性间隔链后,在保持液晶性条件下,可提高非线性结构单元在共聚酯中的摩尔百分含量,即在C_(4-s)/SDP/HQCL系列中SDP的最大含量可达55%(mol),C_(4-s)/BPA/HQCL和C_(6-s)/BPA/HQCL中BPA的最大含量可达40%(mol),而C_(10-s)/BPA/HQCL中为50%(mol)。

Effect of Non-Linear Unit and Flexible Spacer on Liquid Crystal Properties of Copolyester

Flexible spacer, (n=4, 6, 10, abbreviated to C_(4-s), C_(6-s), C_(10-s) respectively) was inserted into the polymer chains of a series aromatic copolyesters obtained from chlorohydroquinone (HQCL) and non-linear biphenol: 4, 4'-sulfonyldiphenol(SDP) or 4,4'-isopropylidenediphenol(BPA). The effect of nonlinear unit of biphenol and flexible spacer on liquid crystal properties of these copolyesters was studied by inherent viscosity, DSC and hot-stage polarized microscopy. The results show that these copolyesters have the typical texture for the nematic state and the maximum mole content of the nonlinear biphenol in these copolyesters without destruction of their liquid crystal properties will increase when the polymer chains hold flexible spacer. It was found that the maximum mole content of SDP in copolyester C_(4-s)/SDP/HQCL was 55%, BPA in C_(4-s)/BPA/HQCL and C_(6-s)/BPA/HQCL was 40%, and in C_(10-s)/BPA/HQCL was 50%.