Novel Polymers by the Radical Polymerization via Addition-Abstraction Mechanism

我们开发了一种新型的自由基聚合，它通过加成-抽象机制传播。合成了三种适合于加成-抽提聚合的单体，并研究了它们的聚合行为。3，3-二氰基丙基乙烯基醚(DCPVE)是一种乙烯基醚，易与过氧化叔丁酯聚合。所得聚合物的相对分子质量在3000-4000之间。聚合物结构的~1H和~(13)C-核磁共振分析表明，聚合几乎定量地通过加成-抽提机理进行。根据单体竞聚率和共聚物的结构，考察了DCPVE与部分乙烯基单体的自由基共聚合反应。共聚反应还在很大程度上涉及到加成-提取机理。邻甲酰基苯基富马酸乙酯(EFPF)在自由基引发剂作用下聚合，产率较高。发现聚合反应是以复杂的方式进行的，包括乙烯基加成和分子内抽氢。聚(EFPF)的相对分子质量在1600-2900之间。聚合体系中含有ESR观察到的传播自由基。根据ESR数据估算了传播和终止的速率常数。研究了EFPF与乙烯基单体的共聚反应，以EFPF为原料合成了邻苯基-1，3-二氧戊环-2-苯基富马酸乙酯(EPDPF)。EFDPF也进行了自由基聚合。聚(EFDPF)的~1H和~~lt；13&gt；C-核磁共振分析表明，在较高的温度下，聚合过程包括乙烯基加成、分子内抽氢和环缩醛的进一步开环。

We have developed a novel type of radical polymerization which propagates through addition-abstraction mechanism. Three monomers suitable for the addition-abstraction polymerization were prepared and their polymerization behaviors were investigated.3,3-Dicyanopropyl vinyl ether (DCPVE), a vinyl ether, was easily polymerized with t-butyl peroxide. The molecular weight of the resulting polymer was in the range of 3000-4000. ^1H-and ^<13>C-NMR analysis of polymer structure revealed that the polymerization almost quantitatively proceeds through addition-abstraction mechanism. Radical copolymerization of DCPVE with some vinyl monomers were examined on the basis of monomer reactivity ratios and structures of copolymers. The copolymerizations also involve the addition-abstraction mechanism to a considerable extent.Ethyl o-formylphenyl fumarate (EFPF) was polymerized by radical initiators in a fairly yield. The polymerization was found to proceed in a complicated manner involving vinyl addition and intramolecular hydrogen-abstraction. The molecular weight of poly (EFPF) was in the range of 1600-2900. The polymerization system involved ESR-observed propagating radicals. The rate constants of propagation and termination were estimated on the basis of ESR data. Copolymerizations of EFPF with vinyl monomers were also examined.Ethyl o- (4-phenyl-1,3-dioxolan-2-yl) phenyl fumarate (EPDPF) was synthesized from EFPF and stirene glycol. EFDPF was also radically polymerized. ^1H- and ^<13>C-NMR analysis of poly (EFDPF) showed that the polymerization proceed in a manner involving vinyl addition, intramolecular hydrogen-abstraction, and further ring-opening of cyclic acetal at higher temperatures.