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综述了辐射接枝、化学处理接枝和等离子体接枝以及其他接枝改性方法的研究进展,并讨论了接枝改性机理和控制接枝过程的重要因素。 相似文献
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用熔融接枝方法制备了聚丙烯蜡接枝丙烯酰胺(PPW-g-AM),用红外光谱、化学滴定法对接枝物进行了定性和定量的表征,讨论了单体、引发剂、反应时间对接枝率和接枝效率的影响。结果表明:在100~110℃下,PPW用量为50g、AM用量为10g、BPO用量为2.0g,反应时间为2h时,可获得最佳的接枝率和接枝效率,并利用红外光谱证实了PPW-g-AM的存在。 相似文献
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聚丙烯固相接枝马来酸酐改性研究 总被引:1,自引:0,他引:1
采用固相法以马来酸酐对聚丙烯粒料(粒径为2.7 mm)进行接枝改性,研究了反应条件对接枝率和接枝效率的影响,通过化学分析、红外光谱、平衡转矩等对接枝聚丙烯进行了表征。结果表明,马来酸酐成功接枝于聚丙烯上,最大接枝率可达2.2%;马来酸酐接枝聚丙烯平衡转矩明显大于接枝空白样,接枝率的大小对平衡转矩影响不大。 相似文献
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MMA与SBS的本体接枝共聚 总被引:2,自引:0,他引:2
本文介绍以过氧化苯甲酰(BPO)为引发剂,用甲基丙烯酸甲酯既作溶剂又作接枝单体与SBS进行的本体接枝共聚反应,研究了反应时间、温度、引发剂浓度及SBS用量对接枝度和接枝率的影响,并用红外光谱、核磁共振和透射电镜检验了所得接枝共聚物的组成和结构。结果表明,用本文所述方法,在适宜聚合条件下可制得具有一定接枝度的SBS-g-MMA接枝共聚物。此法与溶剂型接枝共聚法相比,由于不用其他溶剂,既改善了SBS的性能、简化了操作,又避免了对环境的污染。本文对接枝共聚反应的机理也作了扼要的探讨。 相似文献
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聚苯乙烯溶液接枝改性研究 总被引:1,自引:1,他引:0
研究了丙烯酸丁酯(BA)、聚苯乙烯(PS)的二甲苯溶液,以过氧化二苯甲酰(BPO)为引发剂制备聚苯乙烯/丙烯酸丁酯接枝物的溶液接枝反应.讨论了接枝对聚苯乙烯性能的影响以及反应单体浓度、引发剂用量等因素对接枝率的影响. 相似文献
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悬浮溶胀法合成接枝聚丙烯 总被引:10,自引:1,他引:9
用BPO作引发剂以水相悬浮胀法合成接枝聚丙烯,研究了反应条件、组分等因素对PP的接枝率(Gr)和接枝效率(Ge)的影响,发现溶胀剂、悬浮剂、引发剂、催化剂是该接枝物的主要影响因素。用此方法接枝的聚丙烯有工艺简单,接枝率高,聚丙烯降解程度小等优点,用它作PP/CaCO3、PP/PA6、PP/MBS体系的相容剂,测试结果表明,复合材料的力学性能有很大的提高。 相似文献
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Grafting efficiency is an important indicator of polypropylene grafting reaction. A series of studies have been accomplished, including the conditions of free radical presence on PP backbone during peroxide initiation, the effect of preheat treatment and reaction time on PP suspension grafting results, and the effect of peroxide residue on properties of modified PP. An optimized grafting process was proposed by mixing and preheating polypropylene (PP) and the initiator benzoyl peroxide (BPO) before adding the grafting monomer glycidyl methacrylate (GMA),resulting in an increase in grafting efficiency from 50.0% to 78.2%. With initiator residue removed by alternating temperature treatment, the suspension grafting reaction time could be substantially reduced. 相似文献
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Glycidyl methacrylate (GMA) was grafted on ethylene–propylene copolymer during melt processing with peroxide initiation in the presence and absence of a more reactive comonomer (coagent), trimethylolpropane triacrylate (Tris). The characteristics of the grafting systems in terms of the grafting reaction yield and the nature and extent of the competing side reactions were examined. The homopolymers of GMA (Poly‐GMA) and Tris (Poly‐Tris) and the GMA‐Tris copolymer (GMA‐co‐Tris) were synthesized and characterized. In the absence of the coagent, high levels of poly‐GMA, which constituted the major competing reaction, was formed, giving rise to low GMA grafting levels. Further, this grafting system resulted in a high extent of gel formation and polymer crosslinking due to the high levels of peroxide needed to achieve optimum GMA grafting and a consequent large drop in the melt index (increased viscosity) of the polymer. In the presence of the coagent, however, the grafting system required much lower peroxide concentration, by almost an order of magnitude, to achieve the optimum grafting yield. The coagent‐containing GMA‐grafting system has also resulted in a drastic reduction in the extent of all competing reactions, and in particular, the GMA homopolymerization, leading to improved GMA grafting efficiency with no detectable gel or crosslinking. The mechanisms of the grafting reactions, in the presence and absence of Tris, are proposed. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1401–1415, 2001 相似文献
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多单体接枝技术的研究进展 总被引:3,自引:0,他引:3
综述了多单体接枝技术研究现状,并对共单体的选择和作用机理进行了阐述,介绍了简单且直观的选择共单体的方法——Q-e规则。另外还概述了多单体熔融接枝聚丙烯产物的增容作用。 相似文献