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PAA-b-PNIPAM-b-PAA温敏性共聚物的合成及性能研究

时间:2018-11-28 16:19来源:毕业论文
以S,S′-双(a,a′-二甲基-a″-乙酸)-三硫代碳酸酯(BDATC)作为链转移剂,以丙烯酸(AA)和N-异丙基丙烯酰胺(NIPAM)为原料,通过可逆加成-断裂转移聚合(RAFT)合成了一系列嵌段比不同

摘要本文以S,S′-双(a,a′-二甲基-a″-乙酸)-三硫代碳酸酯(BDATC)作为链转移剂,以丙烯酸(AA)和N-异丙基丙烯酰胺(NIPAM)为原料,通过可逆加成-断裂转移聚合(RAFT)合成了一系列嵌段比不同的聚丙烯酸-b-聚N-异丙基丙烯酰胺-b-聚丙烯酸(PAA-b-PNIPAM-b-PAA)。并使用了核磁共振氢谱(1H NMR)、红外光谱(IR)对共聚物进行表征。利用紫外-可见分光光度仪对共聚物溶液环境响应性进行了探究。实验结果表明共聚物PAA-b-PNIPAM-b-PAA的PNIPAM嵌段的比例越高,相应的异丙基疏水作用比例越大,即其最低临界溶解温度(LCST)越低;共聚物溶液浓度越大,由分子聚集引起的相转变行为所需的温度越低,即其LCST越低;共聚物溶液pH越大,其嵌段PAA的羧基电离越充分,亲水作用加强,使其LCST变大;共聚物PAA-b-PNIPAM-b-PAA溶液的温度响应性行为有着可逆性,并且温度升降循环6次这种可逆性仍然存在。30730
关键词  可逆加成-断裂转移聚合  最低临界溶解温度 温度响应性
毕业论文设计说明书外文摘要
Title Synthesis and properties of PAA-b-PNIPAM-b-PAA   temperature-sensitive copolymer                          
Abstract
In this paper, We use the S, S'- bis (a, a'- dimethyl -a "- acetic acid) - trithiocarbonate (BDATC) as a chain transfer agent, acrylic acid (AA) and N- isopropylacrylamide (NIPAM) as a raw material synthesized a series of different block ratio of polyacrylic acid -b- poly N- isopropylacrylamide -b- polyacrylic acid (PAA-b-PNIPAM -b-PAA) by reversible addition - fragmentation transfer polymerization (RAFT). And the use of nuclear magnetic resonance spectroscopy (1H NMR), infrared spectroscopy (IR) to characterize the structure of the copolymer. By UV - visible spectrophotometer environment responsive to the copolymer solution has been explored. Experimental results show that the higher the proportion of copolymer PAA-b-PNIPAM-b-PAA of PNIPAM block, the corresponding isopropyl greater the proportion of the hydrophobic effect, namely its lower critical solution temperature (LCST) lower. Copolymer concentration, the lower the required molecular aggregation caused by the phase transition temperature behavior, ie the lower the LCST; Copolymer solution pH, the more fully ionized carboxyl its block PAA, the hydrophilic interaction strengthened to LCST increases; Temperature of the copolymer PAA-b-PNIPAM-b-PAA solution with sexual response reversibility, and elevating the temperature cycling 6 times this reversibility persists.
Keywords  Reversible addition - fragmentation transfer polymerization   Lower critical solution temperature   Temperature-responsive
目   录
1  绪论    1
1.1  前言    1
1.2  以PNIPAM为基础的共聚物的合成    1
1.2.1  原子转移自由基聚合(ATRP)    1
1.2.2  氮氧自由基(TEMPO)体系    3
1.2.3  可逆加成-断裂转移聚合(RAFT)    4
1.2.4  阴离子活性聚合    5
1.3  以PNIPAM为基础系列共聚物的自组装    5
1.3.1  温度响应性共聚物    6
1.3.2  温度和pH双重响应性共聚物    6
1.4  以PNIPAM为基础的温敏共聚物的应用    7
1.4.1  生物医药    7
1.4.2  物料分离    8
1.4.3  纳米反应器    8
1.5  本论文的提出和主要研究内容    9
2  嵌段聚合物PAA-b-PNIPAM-b-PAA的合成    10 PAA-b-PNIPAM-b-PAA温敏性共聚物的合成及性能研究:http://www.youerw.com/huaxue/lunwen_26602.html
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