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HDPE/LDPE混合物熔融接枝GMA的研究 总被引:10,自引:2,他引:8
采用熔融接枝的方法,制备了(HDPE/LDPE)-g-GMA(甲基丙烯酸缩水甘油酯)接枝吻,研究了引发剂的用量、GMA的用量、苯乙烯(St)/GMA的配化、转速、反应时间等因素对接枝率的影响。确立了最佳的接枝配方和工艺条件:过氧化二异丙苯(CDP)用量0.1份、GMA用量3份、St用量3份、温度180℃、转速60r/min、反应时间为10min。接枝反应动力学曲线与接枝反应过程的机理特征相吻合。红外光谱的分析结果表明GMA确实接到了大分子链上;DTA分析结果表明,接枝物中GMA的引入导致大分子链的规整性降低,熔融温度略有下降。 相似文献
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淀粉接枝甲基丙烯酸缩水甘油酯共聚物的合成与表征 总被引:1,自引:0,他引:1
以木薯淀粉为原料、过硫酸钾为引发剂,通过乳液聚合法制备淀粉甲基丙烯酸缩水甘油酯(GMA)接枝共聚物,系统考察了反应条件对接枝共聚物接枝率(G)、接枝效率(GE)以及环氧值(EV)的影响,并通过TG-DSC对接枝共聚物结构进行了表征。结果表明:在m(GMA)∶m(淀粉)=2,过硫酸钾浓度为6mmol/L,反应温度60℃,反应时间1h的条件下,可制得接枝率、接枝效率以及环氧值分别为:64.95%、95.57%、4.24mmol/g的接枝共聚物;接枝共聚物热稳定性比原淀粉有所提高。 相似文献
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采用气-固相氯化原位接枝来实现对聚乙烯粉末的改性,将氯化和接枝过程合为一体,大大简化了接枝共聚物的合成过程,为含氯聚合物的改性提供了一个新的手段。以高密度聚乙烯(HDPE)为原料.采用氯化原位接枝法合成了以氯化聚乙烯(CPE)为骨架聚合物,丙烯酸-2-羟基乙酯(HEA)为支链的接枝聚合物,反应中不需要加入任何引发剂。探讨了影响接枝聚合物力学性能的因素及变化规律。实验结果表明接枝聚合物的力学性能较CPE有显著的提高。氯化接枝温度、聚合物氯含量以及HEA单体的加入量对CPE—g—HEA的力学性能有很大的影响。 相似文献
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CPE的接枝共聚及对PVC的增韧改性 总被引:1,自引:0,他引:1
采用氯化原位接枝法制备氯化聚乙烯接枝甲基丙烯酸甲酯(CPE-g-MMA),并对其红外谱图进行了分析,研究了CPE-g-MMA与纳米CaCO3协同增韧PVC.结果表明,CPE-g-MMA在1 730 cm-1处有明显的羰基吸收峰;与CPE相比,CPE-g-MMA具有良好的力学性能;CPE-g-MMA增韧效果显著; CPE-g-MMA与纳米CaCO3对PVC有协同增韧作用. 相似文献
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为提高氯化原位接枝过程中聚乙烯(PE)接枝顺丁烯二酸酐(MAH)的接枝率,加入了第二单体苯乙烯(St).以FTIR,1H-NMR、GPC及凝胶含量研究PE氯化原位接枝MAH/St接枝共聚物(PE-cg-(MAH/St)的结构.实验结果表明:第二单体St的加入可以明显提高MAH的接枝率,同时没有交联结构的产生.研究了反应温度、单体配比、单体总质量分数、氯气流速等对接枝产物PE-cg-(MAH/St)接枝率的影响,并对接枝物的热性能进行了探索.当反应温度控制在80~90℃,MAH/St单体比例为9:7,单体总量16份,氯气流速29 mmol/min,MAH的接枝率可达3.56%. 相似文献
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在高分子共混增容理论与高分子共混物多相体系流变学的指导下,利用合成的CPE与AN,St的三元接枝共聚物对CPE/AS共混体系进行改性。扫描电镜(SEM)测试结果表明三元接枝共聚物加入CPE/AS共混体系后能有效改善体系相容性。增容作用明显。流变性能测试表明,一定量的CPE三元接枝共聚物加入CPE/AS共混体系后,能有效降低体系的熔体粘度,克服了增容与共混熔体粘度增加的矛盾。制备出具有良好力学与加工性能的CPE/CPE三元接枝共聚物/AS共混材料。讨论了共混体系的增容机理与加工流动性改善的原因。研究表明,共混材料中CPE,AS,CPE三元接枝共聚物的含量分别为30,60,10(质量份)时,其综合性能优良。 相似文献
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CR/MMA—BA自交联型接支共聚物 总被引:3,自引:0,他引:3
研究了N-羟甲基丙为安(N-MAA)存在下氯丁橡胶(CR)/甲基丙烯酸甲酯(MMA)-丙烯酸丁酯(BA)的三元接枝共聚及产物性能。结果表明,在引发剂质量为CR的1.8 ̄2.2%,N-MAA质量为CR的1.6-1.8%,BA用量为36%,反应时间为4h,反应温度为80-85℃时产物的性能较优。对产物还进行了红外光谱表征和性能测试。 相似文献
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CPE改性SBS接枝胶粘剂的研制 总被引:4,自引:1,他引:4
研究了CPE、SBS与MMA在甲苯、丁酮混合溶剂中的三元接枝共聚反应,并用红外光谱和扫描电镜对接枝产物进行了表征。结果表明,在SBS接枝体系中引入不超过骨架聚合物(SBS+CPE)总量25%的CPE,可提高所制胶粘剂对PVC人造革的粘合性能。 相似文献
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The graft copolymerization of N-vinylpyrrolidone (VP) onto gelatin was carried out by the following four different initiator systems: AIBN, K2S2O8, H2O2—Fe2+, and Ce4+—HNO3. The last one caused the monomer to lose the double-bond and polymerization ability due to the hydrolysis of the monomer. Using α,α-azobisisobutyronitrile as an initiator, the graft copolymerization of gelatin and N-vinylpyrrolidone in aqueous medium was studied systematically. The relationships between the rate of grafting and the concentration of initiator, monomer, and gelatin were established experimentally. Meanwhile, the rate equation was also derived from the proposed reaction mechanism, and it was similar to the equation previously obtained experimentally. The apparent activation energies for homopolymerization (Eh), graft copolymerization (Eg), and over all polymerization (Ep) were calculated. The graft efficiency and molecular weight of the grafted PVP were measured by hydrolyzing the backbone with hydrochloric acid. The graft copolymers Gel-g-PVP were added into the coating films, and the physical properties of the films, such as hardening ability, dimensional stability, and wetting property were investigated. © 1998 John Wiley & Sons, Inc. J Appl Polym Sci 68: 1485–1492, 1998 相似文献
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Mohamed Mahmoud Nasef Hamdani Saidi Hussin Mohd Nor Khairul Zaman M. Dahlan Kamaruddin Hashim 《应用聚合物科学杂志》1999,73(11):2095-2102
PFA-g-polystyrene graft copolymers were prepared by simultaneous radiation-induced graft copolymerization of styrene onto poly(tetrafluoroethylene-co-perfluorovinyl ether) (PFA) films. The effects of grafting conditions such as monomer concentration, dose, and dose rate were investigated. Three solvents, i.e., methanol, benzene, and dichloromethane, were used as diluents in this grafting system. Of the three solvents employed, dichloromethane was found to greatly enhance the grafting process, and the degree of grafting increased with the increase of monomer concentration until it reached its highest value at a styrene concentration of 60 (vol %). The dependence of the initial rate of grafting on the monomer concentration was found to be of the order of 1.2. The degree of grafting was found to increase with the increase in irradiation dose, while it considerably decreased with the increase in dose rate. The formation of graft copolymers was confirmed by FTIR analysis. The structural investigation by X-ray diffraction (XRD) shows that the degree of crystallinity content of such graft copolymers decreases with the increase in grafting, and consequently, the mechanical properties of the graft copolymers were influenced to some extent. Both tensile strength and elongation percent decreased with the increase in the degree of grafting. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 73: 2095–2102, 1999 相似文献
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借助红外光谱、核磁共振波谱、热量分析和电子显微镜等对氯丁橡胶(CR)与甲基丙烯酸三丁基锡酯(TBTM)在过氧化甲酰存在下,恒温70℃,共聚5h的产物进行了表征,同时对其进行了防霉试验。结果表明,TBTM与CR发生了接枝共聚,产物具有内在的抗策生物性能,可作为青霉和曲霉生长的延缓剂。 相似文献
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高氯氯化聚乙烯对CR与MMA接枝共聚合的影响 总被引:3,自引:1,他引:2
以甲苯为溶剂,在90℃条件下,研究了10份氯含量为57%的高氯氯化聚乙烯(HCPE)对100份粘接型氯丁橡胶与75份甲基丙烯酸甲酯(MMA)接枝共聚合的影响。结果表明,该体系与无HCPE体系相比,MMA转化率约提高40%,产物接枝效率约高50%,接枝度约高90%。产物含有较高相对分子质量的级分,相对分子质量分布较宽,并且有较好的物理机械性能和较高粘接强度。 相似文献