Solid-state graft polymerization of styrene in spherical polypropylene granules in the presence of TEMPO
Solid-state graft polymerization of styrene in spherical polypropylene granules in the presence of TEMPO
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DOI：
10.1002/app.29415
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发表时间：
2009-04
影响因子：
3
通讯作者：
F. Sun;Zhisheng Fu;Qingtian Deng;Zhiqiang Fan
中科院分区：
文献类型：
--
作者：
F. Sun;Zhisheng Fu;Qingtian Deng;Zhiqiang Fan
以球形等规聚丙烯（PP）为基体，在过苯甲酸叔丁酯（TBPB）和2，2，6，6-四甲基哌啶氧基（克里思）存在下，通过固相接枝苯乙烯（St）制备了一系列PP接枝聚苯乙烯（PP-g-PS）。考察了克里思与TBPB的配比、TBPB用量、St用量、反应时间、反应温度等反应条件。克里思的加入使PP的接枝率略有下降，但减少了凝胶的形成和PP链的降解。樟脑磺酸的引入使PP-g-PS的分子量明显增加，凝胶形成量减少，但凝胶度变化不大。加入克里思合成的产物的GPC曲线在高分子量端有明显的拖尾。产物熔体的复数粘度随角频率的变化表现出明显的剪切变稀行为。实验结果表明接枝产物中存在长支链。© 2008 Wiley Periodicals，Inc.应用聚合物科学杂志，2009年
A series of polypropylene-graft-polystyrene (PP-g-PS) were prepared by solid-state graft polymerization of styrene (St) in the presence of tert-butyl perbenzoate (TBPB) and 2,2,6,6-tetramethyl-piperidinyloxy (TEMPO) using nascent spherical isotactic polypropylene (PP) granules as matrix. Reaction conditions such as ratio of TEMPO to TBPB, amount of TBPB and St, reaction time and temperature were investigated. The grafting degree (GD) decreased slightly with the addition of TEMPO, but the introduction of TEMPO reduced gel formation and degradation of PP chain. Introduction of camphor sulfonic acid in the TEMPO-mediated grafting polymerization system lead to evident increase in molecular weight of PP-g-PS and decrease of gel formation with slight changes of GD. GPC curves of the product synthesized with TEMPO addition showed obvious tailing at high molecular weight end. Complex viscosity in dependence on angular frequency of the melt of product showed obvious shear-thinning behaviors. All the experimental results indicated existence of long-chain branches in the product of graft polymerization. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009