甲壳型液晶高分子论文：基于半刚性温敏性无规共聚物的合成与表征.doc

甲壳型液晶高分子论文：基于半刚性温敏性无规共聚物的合成与表征【中文摘要】温敏性聚合物能够对外界环境的温度刺激做出响应,已得到越来越多的应用。目前,合成的温敏性聚合物中,其链段绝大多数为柔性链段；虽然部分温敏性天然高分子及其衍生物具有半刚性的链段结构,但是这类高分子却难以合成和控制。甲壳型液晶高分子(MJLCP)是一种典型的半刚性链结构的聚合物,但现有甲壳型液晶高分子均为疏水性的,不溶解于水中,所以不是水溶性温敏性聚合物。因此,设计并合成基于甲壳型液晶高分子的温敏性聚合物在理论和应用中都具有极大的意义。本论文通过无规共聚的方法合成了三种新型的半刚性温敏性共聚物,并重点研究了不同单体组成的共聚物的本体性质和溶液性质。主要做了如下工作：1.成功合成了乙烯基对苯二甲酸二(N-羟乙基吡咯烷酮)酉旨(NHEPVTA)和乙烯基对苯二甲酸二(4-甲氧基)苯酯(MPCS)的无规共聚物P(MPCS-co-NHEPVTA),并考查了共聚物的本体和溶液性质。结果发现,共聚物仅表现出一个玻璃化转变；且不同MPCS含量的共聚物均表现出液晶性,这与我们理论上的推测是一致的；MPCS的含量变化时,共聚物的低临界溶解温度(LCST)会随着MPCS含量的升高而显著的降低；当MPCS的含量达到4%以上时,共聚物不溶于水。2.成功合成了乙烯基对苯二甲酸二(N-羟乙基吡咯烷酮)酯(NHEPVTA)和苯乙烯(St)的无规共聚物P(St-co-NHEPVTA),并考查了共聚物的本体和溶液性质。结果表明,该共聚物仅表现出一个玻璃化转变；当共聚物中苯乙烯含量为20%以上时,共聚物不再表现出液晶性；共聚物的LCST会随着苯乙烯含量的升高而明显的降低；当苯乙烯的含量达到30%以上时,共聚物不溶于水。3.成功合成了乙烯基对苯二甲酸二(N-羟乙基吡咯烷酮)酯和丙烯酰胺(AM)的无规共聚物P(AM-co-NHEPVTA),用GPC和DSC对其本体性质进行了研究,并用目测法考查了溶液的温敏性。研究表明,与一般的甲壳型液晶高分子类似,共聚物只表现出了一个玻璃化转变；当AM的含量直到70%的时候,共聚物仍具有液晶性；亲水性的AM含量变化时,共聚物的LCST随着AM含量的增加而降低。经过上述实验,证明了通过调节不同亲疏水性单体的比例,可以制备兼具液晶性和温敏性的共聚物,且该共聚物的液晶性和温敏性可以进行较好的调控。【英文摘要】Due to reversible property changes in response to temperature, thermoresponsive polymers have attracted considerable research interests. However, the main-chains of these synthesized thennoresponsive polymers are mostly flexible and some of the thennoresponsive natural polymer and its derivatives segment with semi-rigid structure were difficult to molecular design and synthesis, all those hinder further research of these polymers.Mesogen-Jacketed Lliquid Crystal Polymer (MJLCP) is a typical semi-rigid synthesized polymer, but it is hardly water-solubled. Therefore, how to design and synthesize a novel polymer based on MJLCPs exhibited thennoresponsive property is very significance.Three novel thermoresponsive copolymers with the semi-rigid were synthesized via random copolymerization, and we focus on the body and solution properties.At first, synthesized random copolymer poly2.5-bis(4-methoxyphenyl) oxycarbonylstyrene-co-bis-(N-hydroxyethylpyrrolidone)2-vinylterephthalate (P(MPCS-co-NHEPVTA), and investigated the body and solution properties of copolymers. The copolymers showed only one glass transition. And the results were consistent with our theory judgments:different MPCS content of copolymers have shown character of liquid crystalline. With the MPCS content increased copolymers the lower critical solution temperature (LCST) decreased evidently. The copolymers were almost insoluble in water when the content of MPCS more than 4%.Synthesized random copolymer polystyrene-co-2.5-bis(4-methoxyphenyl) oxycarbonylstyrene(P(St-co-NHEPVTA) and investigated the body and solution properties of copolymers. The copolymers showed only one glass transition. When the content of St more than 20%, the copolymer not showed liquid crystalline. With the St content increased copolymers LCST decreased evidently. The copolymers were almost insoluble in water When the content of PS more than 30%.Last, semi-rigid thennoresponsive copolymer polyacrylamide-co-2.5-bis (4-methoxyphenyl)oxycarbonylstyrene (P(AM-co-NHEPVTA)have been successfully synthesized、and some properties in bulk were confirmed by GPC and DSC, at the same time, the thennoresponsive properties in solution were confirmed by visual observation. The results show that these polymers have the properties in bulk similar to MJLCPs, i.e., the just only one glass transition in these polymer. On the other hands, the liquid crystallinity didnt disappeared when the content of AM reached 70%. Moreover, with the increase in hydrophilic AM content, the LCST of copolymer would increase.All the experimential results show tha both liquid crystalline and thermoresponsive properties of the polymers could be contralled by adjusted the ratio of different hydrophilic and hydrophobic monomers. Furthermore, we would used these polymer to make some intelligent materials, and this work is under going.【关键词】甲壳型液晶高分子 液晶性 温敏性 半刚性 低临界溶解温度【英文关键词】mesogen-jacketed liquid crystal polymer liquid crystallinity thermoresponsive semi-rigid LCST【目录】基于半刚性温敏性无规共聚物的合成与表征摘要4-5Abstract5-6第1章 绪论9-241.1 引言91.2 液晶高分子9-161.2.1 液晶高分子概述9-111.2.2 液晶高分子分类及基本特性111.2.3 甲壳型液晶高分子11-161.3 温敏性聚合物16-231.3.1 智能型聚合物简介16-171.3.2 温敏性聚合物的常见种类17-211.3.3 温敏性聚合物的相分离机理和LCST的调节21-221.3.4 温敏性聚合物的应用前景22-231.4 本文的选题及设计思路23-24第2章 温敏性共聚物P(MPCS-co-NHEPVTA)的合成及其本体性质与温敏性的研究24-322.1 引言242.2 实验部分24-272.2.1 主要试剂来源与处理24-252.2.2 仪器与测试条件252.2.3 单体及共聚物的合成25-272.3 结果与讨论27-312.3.1 NHEPVTA的合成与表征27-282.3.2 共聚物P(MPCS-co-NHEPVTA)的合成与表征282.3.3 共聚物P(MPCS-co-NHEPVTA)的本体性质研究28-312.4 小结31-32第3章 温敏性共聚物P(St-co-NHEPVTA)的合成及其本体性质与温敏性质的研究32-373.1 引言323.2 实验部分32-333.2.1 主要试剂来源与处理323.2.2 仪器与测试条件32-333.2.3 共聚物P(St-co-NHEPVTA)的合成333.3 结果与讨论33-363.3.1 共聚物P(St-co-NHEPVTA)的合成与表征333.3.2 共聚物P(St-co-NHEPVTA)的本体性质研究33-363