可逆加成—断裂链转移（RAFT）法制备功能性聚合物

发布时间：2018-04-16 17:14

本文选题：RAFT聚合 + 功能性聚合物　；参考：《北京化工大学》2011年博士论文

【摘要】：本论文考察了可逆加成-断裂链转移(RAFT)聚合法对甲基丙烯酸-2-羟乙酯、丙烯酸、马来酸酐、正丁基乙烯基醚等功能性单体进行活性自由基聚合,得到了一系列的功能性聚合物,具体如下： (1)以偶氮二异丁腈(AIBN)为引发剂,在RAFT试剂二硫代苯甲酸(2-乙氧基羰基)-2-丙酯(EPDB)存在条件下,分别以甲基丙烯酸甲酯(MMA)/甲基丙烯酸-2-羟乙酯(HEMA)、MMA/丙烯酸(AA)、马来酸酐(MAn)/苯乙烯(St)等多种带有功能性基团的单体进行自由基聚合,得到分子结构可控、相对分子质量(简称“分子量”)可控及分子量分布较窄的共聚物。 (2)以MMA/HEMA为单体进行RAFT聚合得到分子量可控的无规共聚物P(HEMA-co-MMA),利用其侧链羟基与二元乙烯基醚1,4-环己烷甲醇二乙烯基醚(CDE)进行加成发应,生成了交联链段中含有缩醛结构的聚合物凝胶,这种凝胶在酸性条件下可以迅速降解为可溶性的线型聚合物。 (3)以MMA/AA为单体进行RAFT聚合得到分子量可控的无规共聚物P(AA-co-MMA),利用其侧链羧基与二元乙烯基醚二(亚甲基-4,1-二苯基)氨基甲酸二[4-(乙烯氧基)]丁酯(BECT)进行加成发应,生成了交联链段中含有半缩醛结构的聚合物凝胶,这种凝胶在酸性条件下可以迅速降解为可溶性线型聚合物。 (4)以MAn/St为单体进行RAFT聚合,通过调节体系中St与MAn的比例,得到一系列分子量可控的嵌段共聚物P(MAn-alt-St)m-b-(St)n。并利用动态光散射(DLS)对其水解产物在水溶液中的自组装行为及在乳液聚合体系中的应用进行研究。 (5)以MAn和正丁基乙烯基醚(n-BVE)为单体进行RAFT聚合,考察RAFT试剂对MAn与n-BVE共聚体系的可控性。 (6)利用羟基与异氰酸酯基团反应具有高活性的特性,以HBVE和二苯基亚甲基二异氰酸酯(MDI)为原料合成了二元乙烯基醚单体BECT,且反应条件温和、收率较高。 (7)以二元乙烯基醚BECT为偶联剂,与AA和HEMA反应分别生成二(亚甲基-4,1-二苯基)氨基甲酸二[4-(1-丙烯酰氧基)乙氧基]丁酯(BABE)和二(亚甲基-4,1-二苯基)氨基甲酸二{4-[1-(2-甲基丙烯酰氧基)乙氧基]乙氧基}丁酯(BMBE),二者分子结构中都含有(半)缩醛及双烯烃结构,可以作为可降解型交联剂使用。 (8)以MAn和正丁基乙烯基醚(n-BVE)/4-羟丁基乙烯基醚(HBVE)进行自由基交替共聚,通过改变体系中HBVE的含量来调节聚合物分子链中羟基的含量。在催化剂存在下,MAn和n-BVE/HBVE的共聚物与二元乙烯基醚BECT进行交联反应生成聚合物凝胶,这种凝胶的交联链段中含有缩醛结构,在酸性条件下可以迅速降解为可溶性的线型聚合物。 (9)以BABE和BMBE为交联剂,用于MMA的溶液自由基聚合和悬浮自由基聚合体系,分别得到PMMA凝胶和PMMA凝胶粒子,在有机溶剂中可以充分溶胀而不溶解。由于交联链段中含有(半)缩醛单元,因此在酸性条件下聚合物凝胶及凝胶粒子可以快速降解,生成可溶性的线型聚合物。
[Abstract]:In this paper, a series of functional polymers were obtained by reversible addition-break chain transfer polymerization (Raft) polymerization of functional monomers such as ethyl methacrylate, acrylic acid, maleic anhydride, n- vinyl ether and so on.The details are as follows:Using azodiisobutyronitrile (AIBN) as initiator, in the presence of RAFT reagent, 2-ethoxycarbonyl carbonyl-2-propyl ester (EPDBs),The molecular structure was controlled by the free radical polymerization of MMAO / HEMAA / AAA, MAnan / Str, respectively, with functional groups, and the molecular structure was controlled by free radical polymerization with methyl methacrylate (MMA) / 2-hydroxyethyl methacrylate (Hema) / acrylic acid (AAA), and maleic anhydride (MA) / styrene-butadiene (St), respectively.Copolymers with controlled molecular weight and narrow molecular weight distribution.PHEMA-co-MMA-Copolymer with controllable molecular weight was synthesized by RAFT polymerization with MMA/HEMA as monomer. The side chain hydroxyl group of PHEMA-co-MMA-PHEMA-co-MMA-PHEMA-co-MMA-PHEMA-co-MMA-PHEMA-co-MMA-PHEMA-co-MMA-Copolymer was prepared by RAFT polymerization with MMA/HEMA as monomer.A polymer gel with acetal structure in the crosslinked segment was formed, which can be rapidly degraded into soluble linear polymer under acidic conditions.In this paper, a random copolymers (PnAA-co-MMAA) with controllable molecular weight were synthesized by RAFT polymerization using MMA/AA as monomer. The side chain carboxyl group was used to perform addition reaction with dicarboxylether bis (methylene 4-diphenyl) carbamate [4-( ethylene oxy)] butyl ester (BECT).A polymer gel with a semi-acetal structure in the crosslinked segment was formed, which can be rapidly degraded into a soluble linear polymer under acidic conditions.A series of block copolymers with controllable molecular weight were obtained by RAFT polymerization with MAn/St as monomer and by adjusting the ratio of St to MAn.The self-assembly behavior of its hydrolysate in aqueous solution and its application in emulsion polymerization system were studied by dynamic light scattering (DLS).(5) RAFT polymerization was carried out with MAn and n- vinyl ether (n-BVEE) as monomers to investigate the controllability of RAFT reagent on the copolymerization of MAn and n-BVE.The binary vinyl ether monomer (BECT) was synthesized from HBVE and diphenyl methylene diisocyanate by the reaction of hydroxyl groups with isocyanate groups. The reaction conditions were mild and the yield was high.Using binary vinyl ether BECT as coupling agent,Reaction with AA and HEMA to produce bis (methylene -4- (1-diphenyl) carbamate) bis [4-chrylacryloxy) ethoxy] butyl ester (Babe) and bis (methylene -41-diphenyl) carbamate bis {4- [1-dimethacryloxy) ethoxy] ethoxy, respectively.BMBEN, both of which contain (semi-acetal) and diolefin structures,It can be used as a degradable crosslinking agent.The hydroxyl groups in the polymer chain were adjusted by changing the content of HBVE in the polymer chain by radical alternating copolymerization with MAn and n-BVEE / 4-hydroxyl Ding Ji vinyl ether (HBVEE).In the presence of catalyst, the copolymers of man and n-BVE/HBVE reacted with binary vinyl ether (BECT) to form polymer gels. The crosslinked segments of these gels contain acetal structures and can be rapidly degraded into soluble linear polymers under acidic conditions.Using BABE and BMBE as crosslinkers, the solution free radical polymerization and suspension radical polymerization system of MMA were used to obtain PMMA gel and PMMA gel particles, which could be fully swelled and insoluble in organic solvents.Due to the presence of (semi-acetal) units in the crosslinked segments, polymer gels and gel particles can be rapidly degraded to form soluble linear polymers under acidic conditions.
【学位授予单位】：北京化工大学
【学位级别】：博士
【学位授予年份】：2011
【分类号】：O631.5

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