热致液晶聚合物(TLCP)的溶解性研究

摘要

以对羟基苯甲酸(HBA)、联苯二酚(BP)、9,9-二(4-羟基苯基)芴(双酚芴BHPF)、对苯二甲酸(TA)和间苯二甲酸(IA)为单体,醋酸酐为酰化试剂,乙酸镁为催化剂,在程序升温条件下合成了两种热致性液晶聚合物,并采用固相聚合工艺对预聚物进行增黏处理,通过红外(FTIR)、热失重分析(TG)、差示扫描量热分析(DSC)、超景深三维显微镜(偏光模式)、扫描电镜(SEM)、毛细管溶液黏度、熔融剪切黏度、色度测试、溶解性实验以及力学性能测试进行了表征分析.结果发现,以具有大侧基的非平面双酚芴结构部分替代线性联苯二酚结构合成的TLCP溶解性提高,说明通过大侧基和非平面的结构引入能够在一定程度上提高液晶聚合物的溶解性能,但由于分子链中线性棒状结构的减少,其液晶性能有所下降.%Two kinds of thermotropic liquid crystalline polymer (TLCP) based on p-hydroxybenzoic acid,4-hydroxybenzoic acid (HBA),4,4'-dihydroxybiphenyl (BP),9,9-Bis (4-hydroxyphenyl) fluorine (BHPF),terephthalic acid (TA) and isophthalic acid (IA) were prepared by pre-polymerization and solidstate polymerization using acetic anhydride as acylation agent and magnesium acetate as catalyst.The structures and performances were confirmed by Fourier transform infrared spectroscopy (FTIR),thermogravimetry (TG),differential scanning calorimetry (DSC),polarized light microscopy (PLM),scanning electron microscope (SEM),capillary tube viscosimeter,melt shear viscosity,colour photometer,solubility experiment and mechanical properties testing.The results show that bisphenol fluorine with big side group and non-planarstructure replacing the linear biphenyl structure partly to synthesis of TLCP has good solubility,introducing the structure of the big side group and non-planar structure in a certain extent can improve the solubility properties of liquid crystal polymer,but the liquid crystal performance reduces with the decrease of the linear rod molecule in molecular chain.