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Maleic anhydride grafting onto polypropylene was conducted in a twin‐screw extruder according to an experimental design in which the maleic anhydride and peroxide concentrations were varied. The modified polypropylene was characterized by FTIR spectroscopy, melt‐flow index measurements, size‐exclusion chromatography, differential scanning calorimetry, and nuclear magnetic resonance. The results showed that only the independent variable peroxide concentration influenced the amount of reacted maleic anhydride, whereas the two variables studied influenced the molecular weight of the grafted polypropylene. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 2706–2717, 2002 相似文献
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The copolymerization of styrene (St) and maleic anhydride (MA) was carried out in supercritical carbon dioxide (SC CO2). It was found that St and MA are easy to copolymerize in SC CO2 and the conversion can reach 97%, and that very fine and dry powders are obtained. The products were characterized using Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), scanning electron microscopy (SEM), differential scanning calorimetry (DSC), and thermogravimetric analysis (TGA). GPC data showed that the molecular weight of the copolymer reach 3.62 × 104 g mol?1. Scanning electron microphotographs showed the minimum particle size of the product is about 200 nm. DSC measurements indicated that the glass transition temperature (Tg) of the copolymer increases with increasing the MA content in the copolymer. TGA curve showed that the copolymers were decomposed at about 350°C. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007 相似文献
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ABS反应挤出接枝马来酸酐研究 总被引:7,自引:0,他引:7
要反应挤出接枝技术,在ABS上接枝MAH,探讨了ABS性能、MAH用量、引发剂品种和用量对MAH接枝率的影响。并用MAH接枝ABS与PA6制成合金,其性能达到国内外同类产品水平。 相似文献
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POE/PP体系的反应挤出接枝马来酸酐研究 总被引:4,自引:0,他引:4
通过研究辛烯-乙烯共聚物/聚丙烯(POE/PP)比例。第二反应单体的选择,马来酸酐(MAH)单体和过氧化二异丙苯(DCP)用量变化以及反应温度,螺杆转速,真空度对接枝产品性能的影响情况,找出了适合于工业生产的最佳配方和工艺条件,即POE/PP为60:40,MAH为1.5%,DCP为0.04%,提纯苯乙烯为1.5%。螺杆转速为45r/min,真空度为-0.10MPa,螺筒各段温度为160,190(反应段),190(除杂段),150(机头)℃。 相似文献
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了提高非极性聚丙烯纤维(PP)的相容性,采用固相法以马来酸酐(MAH)对聚丙烯纤维进行接枝改性,研究了反应条件对接枝率的影响。结果表明,马来酸酐成功接枝到聚丙烯上,当反应温度为80℃,PP用量为0.5 g,MAH用量为0.2 g,BPO用量为0.05 g,回流时间为2.5 h时,最大接枝率可达到7.51%;BPO的用量、MAH单体的用量以及反应温度对PP纤维的接枝率影响较大。而测定PP纤维接枝率时回流时间对其接枝率的影响不大;接枝聚丙烯纤维的分解温度明显高于纯聚丙烯纤维。 相似文献
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研究了马来酸酐(MAH)在螺杆挤出机中与聚苯乙烯的接枝反应,确定了挤出接枝反应的最佳工艺条件,初步探索了温度、螺杆转速、引发剂浓度以及MAH浓度对接枝反应的影响。 相似文献
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František Kučera Josef Petruš Radka Bálková Josef Jančář 《Polymer Engineering and Science》2020,60(5):1076-1082
Polypropylene (PP) was modified with maleic anhydride (MAH) via heterogeneous solid-state radical grafting performed in a fluidized polymerization reactor. The effect of PP morphology and different concentration of initiator (dibenzoyl peroxide, DBP) on the course of the reaction and grafting efficiency was evaluated with using infrared spectroscopy, scanning electron microscopy (SEM) and particle surface analysis (BET method). With respect to obtained results, the reaction course can be strongly affected by the reaction conditions and PP morphology. Unlike the reactive modification in melt, heterogeneous reaction exhibits lower extent of β-scission albeit the reaction conversion is lower. Solid-state grafting can be used as an alternative method for the surface modification of nonpolar surfaces with polar monomers under mild conditions. 相似文献
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Eduardo A. Gonzalez de los Santos Maria Josefina Lozano Gonzalez Maria Concepcion Gonzalez 《应用聚合物科学杂志》1998,68(1):45-52
The mechanochemical reaction of modificated of polypropylene (PP) with maleic anhydride (MAH) has been studied by ultrasonic irradiation as an energy source at 60°C. Through 23 factorial experimental design, three variables and their interactions were studied: the percentage of MAH, the percentage of benzoyl peroxide (BPO), and ultrasonic irradiation intensity (Watts). According to the results, an increase of wt % of MAH gave a negative effect in the grafting yield; in addition, this negative effect was observed in the interaction of MAH : BPO at a high range of wt %, this behavior is attributed to the homopolymerization of MAH at the experimental conditions employed. The higher positive effect onto the grafting yield was observed for the variable watts (ultrasonic irradiation intensity), even at low intensity. The better interaction of variables gave a MAH grafting degree of 4.65 wt % (93% yield). In addition, the effect of ultrasonic irradiation on the number-average molar mass (Mn), weight-average molar mass (Mw), and polydispersity index (Mw/Mn) was measured. It was observed that the Mw decreased 13.73% and the Mw/Mn also decreased by 11.98%. The o observed effect was attributed to the degradation mechanism induced by the ultrasound, which consists in the generation of macroradicals and their recombination. The product PP-g-MAH was characterized by infrared spectroscopy, also was used to prepare polypropylene–nylon-6 blends. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68:45–52, 1998 相似文献
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HDPE-g-MAH改性氢氧化铝阻燃PP 总被引:1,自引:0,他引:1
在液相中用马来酸酐接枝高密度聚乙烯(HDPE-g-MAH)表面改性Al(OH)_3以改善其在高分子基相中的分散性。形态观察表明,用适量HDPE-g-MAH处理Al(OH)_3可改善Al(OH)_3在聚丙烯(PP)中的分散性,从而提高体系的力学性能;HDPE-g-MAH用量过多造成的Al(OH)_3粒子间桥联,该现象经熔融混合后依然存在,导致力学性能降低。偏光显微镜观察显示,适量HDPE-g-MAH处理Al(OH)_3可改善PP的结晶形态。 相似文献
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P. F. Song M. Xiao F. G. Du S. J. Wang L. Q. Gan G. Q. Liu Y. Z. Meng 《应用聚合物科学杂志》2008,109(6):4121-4129
Terpolymerization of carbon dioxide (CO2) with propylene oxide (PO) and maleic anhydride (MA) was successfully carried out using supported zinc glutarate catalyst. Consequently giving high molecular weight poly(propylene carbonate maleate) (PPCMA) in a very high yield (72.5 g polymer/g catalyst). The resulting terpolymers were fully characterized by FTIR, 1H NMR, 13C NMR, and wide‐angle X‐ray diffraction (WAXD) techniques. NMR measurements showed that PPCMA had an almost alternating structure for the components of carbon dioxide and PO. The influence of molecular weight and MA content on the properties of PPCMA was also investigated. Differential scanning calorimetry (DSC) measurements revealed that the glass transition temperature (Tg) of PPCMA increased with increasing molecular weight. Thermogravimetric analysis (TGA) indicated that PPCMA51 exhibited a very high decomposition temperature (263°C) due to the introduction of the double bond of MA into the backbone of terpolymer. The terpolymers with double bonds can be readily subjected to crosslinking reaction in high temperature to give a slightly crosslinked PPCMA, which exhibit superior thermal stability. Tensile tests also showed that the mechanical properties of PPCMA increased with increasing molecular weight. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008 相似文献
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采用溶液法制备了马来酸酐接枝聚丙烯。采用单因素及正交实验方法研究了单体、引发剂用量、反应温度、反应时间、溶剂用量及引发剂加入工艺等因素对产物接枝率的影响。结果表明,各因素对聚丙烯接枝率都有一定的影响,马来酸酐及二甲苯的用量对聚丙烯接枝率影响最大,当马来酸酐、二甲苯与聚丙烯之间比例为0.1/2/1时,聚丙烯的接枝率最大,接枝率可达4.36%。 相似文献
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