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摘要：以醋酸乙烯酯（VAc）作為聚合單體，偶氮二異丁腈（AIBN），含乙烯基和二硫代酯結(jié)構(gòu)的v-RAFT作為鏈轉(zhuǎn)移劑和支化試劑，苯為溶劑在70oC下進行可逆加成-斷裂轉(zhuǎn)移自由基（RAFT）聚合，制備出超支化聚醋酸乙烯酯，采用氣相色譜（GC）、核磁（1H-NMR）進行跟蹤測定聚合過程，三檢測凝膠滲透色譜（GPC）表征分析超支化聚合物的支化結(jié)構(gòu)。通過研究聚合機理和支化聚合物結(jié)構(gòu)的表明：聚合過程中呈一級線性增長關系，符合活性可控的特征，當反應大概30小時左右單體的轉(zhuǎn)化率就能達到90%以上，基于RAFT試劑含有可聚合的乙烯結(jié)構(gòu)，聚合物的分子量分布隨著轉(zhuǎn)化率的提升不斷變寬，表明聚合物的支化結(jié)構(gòu)為逐步形成和發(fā)展的。根據(jù)凝膠滲透色譜（GPC）、核磁（1H-NMR）等手段的檢測手段進一步深入研究聚合物的支化結(jié)構(gòu)，表明隨著單體的轉(zhuǎn)化率提升，聚合物的支化度不斷增加，高支化聚合物的組分不斷增加，但聚合物的PDI仍然比較小。 關鍵詞：聚合單體；可逆加成-斷裂轉(zhuǎn)移自由基聚合；醋酸乙烯酯
Abstract：Refined vinyl acetate as an initiator monomer , AIBN as catalyst system ,RAFT reagent as a chain transfer agent , Vinyl acetate occer Reversible Addition-Fragmentation Transfer Radical Polymerization at 70oC in Benzene.Using gas chromatography, gel permeation chromatography, nuclear magnetic track determination of the polymerization process , to characterize the branching structure of the polymer . The studies on Polymerization mechanism and Characterization of polymer morphology:In the process of polymerization , from the kinetic curves can be seen , about 30 hours the conversion rate can reach more than 90%;According to Gel Permeation Chromatography(GPC),nuclear magnetic resonance (1H-NMR) , and other means of detection of Reversible Addition-Fragmentation Transfer radical polymerization (RAFT) in the conversion of changing circumstances, the degree of branching of the polymer is increasing;Polymer with the reaction in the RAFT system, high component increasing , but the PDI of the polymer is still relatively low. Key words：initiating monomer, Reversible Addition-Fragmentation Transfer radical polymerization, Vinyl acetate.
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