尾链和间隔基长度对Hemiphasmidic侧链液晶高分子相行为的影响研究

发布时间：2018-06-23 13:57

  本文选题：侧链型液晶高分子 + Hemiphasmidic液晶基元　； 参考：《湘潭大学》2017年硕士论文

【摘要】：本文设计合成了一系列含有hemiphasmidic液晶基元的侧链型液晶高分子(SCLCPs),通过改变末端基团多条烷基尾链的长度、柔性间隔基的长度,利用热分析、X射线衍射等测试手段,详细研究侧基空间体积、耦合作用对SCLCPs相行为及其自组装行为的影响。因此,本文合成了以下两个系列聚合物,并系统研究其相行为和凝聚态结构:1.设计并合成一系列含有不同烷基尾链长度的无柔性间隔基侧链型液晶高分子--聚[4’-(3,4,5-三烷氧基苯)氧羰基]-联苯-氧羰基-甲基丙烯酸(PTmBMA,m为烷基尾链的碳原子数)。研究结果表明,烷基尾链长度对这种含有hemiphasmidic液晶基元的侧链型液晶高分子的相行为及其自组装行为有着重要的影响。含有较短烷基尾链的PT6BMA在低温下能形成长程有序的近晶A(SmA)相,高温下为各向同性相。随着烷基尾链长度的增长,聚合物PTmBMA(m≥8)形成了长程有序的六方柱状相(Φh)。由于烷基尾链和苯环结构的微相分离作用和侧基空间效应,聚合物PTmBMA(m≥8)柱状结构中的每一根柱子由多条高分子(4~5)自组装形成。2.设计并合成一系列含有不同间隔基长度的侧链型液晶高分子--聚[4’-(3,4,5-三癸烷氧基苯)氧羰基]-联苯-氧-烷基-甲基丙烯酸(P-n-BP,n为间隔基的碳原子数)。研究结果表明,柔性间隔基长度对这种含有hemiphasmidic液晶基元的侧链型液晶高分子的相行为及其自组装行为有着重要的影响。含较短间隔基的P-2-BP和P-4-BP形成长程有序的六方柱状相(Φh1),并且P-4-BP在高温下形成了更加有序的六方柱状相(Φh2)。P-6-BP和P-8-BP为过渡态,在低温下形成长程有序的近晶A(SmA)相;在高温下,由于熵驱动形成长程有序的六方柱状相(Φh)。而对于P-10-BP,由于去耦合作用增强,聚合物在低温下形成近晶A(SmA)相,在高温下为各向同性态。
[Abstract]:In this paper, a series of side chain liquid crystal polymers (SCLCPs) with hemiphasmidic liquid crystal units have been designed and synthesized. By changing the length of the end groups of multiple alkyl tail chains, the length of flexible spacers, and by means of thermal analysis, X-ray diffraction, etc., a series of side chain liquid crystalline polymers (SCLCPs) have been designed and synthesized. The effects of space volume and coupling on the phase behavior and self assembly behavior of SCLCPs were studied in detail. Therefore, the following two series of polymers have been synthesized, and their phase behavior and condensed matter structure have been systematically studied. A series of non-flexible spaced side chain liquid crystal polymers, poly [4n- (3- (3-) -trialkoxy benzene) oxycarbonyl] -biphenyl-oxycarbonyl-methacrylic acid (PTmBMAM), were designed and synthesized with different alkyl tail chain lengths (PTmBMAM as the number of carbon atoms in the alkyl tail chain). The results show that the length of the alkyl tail chain has an important effect on the phase behavior and self-assembly behavior of the side chain liquid crystal polymer containing hemiphasmidic liquid crystal unit. PT6BMA with short alkyl tail chain can form a long ordered near crystal A (SmA) phase at low temperature and isotropic phase at high temperature. With the length of alkyl tail chain increasing, the polymer PTmBMA (m 鈮，

本文编号：2057346