DHBA和THBA接枝RSMA侧链液晶高分子的合成

采用溶液缩聚法，将合成的对羟基苯甲酸二聚体（DHBA），四聚体（THBA）接枝到苯乙烯－马来酸酐无规共聚物（RSMA）侧链上，并在主链与刚性侧链之间引入一个CH2柔性间隔；讨论了侧链结构与聚合物液晶性的关系，结果表明DHBA和THBA与RSMA或RSMA－g-HOCH2COOH反应的产物均为接枝共聚物，都表现出向列型液晶行为；RSMA－g-DHBA和RSMA－g-THBA只出现一个玻璃化温度，并且比RSMA的Tg要高，RSMA－CH2－DHBA和RSMA－CH2－THBA共聚物中引入的CH2柔性间隔起去偶作用，减小了刚性侧链与主链之间的相互作用，使共聚物表现出双玻璃化现象。

Synthesis of side-chain liquid crystalline random styrene-maleic anhydride copolymers grafted by dimer and tetramer of p-hydroxybenzoic acid

Dimer (DHBA) and tetramer (THBA) of p hydroxybenzoic acid (HBA) were synthesized and grafted onto the random styrene maleic anhydride copolymer (RSMA) by condensation polymerization. At the same time, the CH 2 flexible spacers were introduced between the main chains and rigid side chains. The effects of side chain structure and flexible spacers on the liquid crystallinity of grafting polymers were discussed. It was found that the products obtained from RSMA or RSMA g HOCH 2COOH reacted with DHBA and THBA were grafting copolymers, all showing nematic phases. The RSMA g DHBA and RSMA g THBA copolymers had only one glass transition, and their glass transition temperatures were higher than that of RSMA. After the CH 2 flexible spacers were introduced between the main chains and rigid side chains of these copolymers, the RSMA CH 2 DHBA and RSMA CH 2 THBA grafting copolymers had two glass transitions due to the de coupling effect of flexible spacers.