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LDPE—g—MAA作为基体树脂的防雾膜的研制 总被引:3,自引:3,他引:3
通过熔融挤出制备了PE-g-MAA接枝共聚物,然后与一定量的防雾滴剂共混吹塑成像,研究了接枝过程中的各种因素对PE(聚乙烯)防雾膜的防雾期及其他性能的影响。研究表明:接枝PE作为基体树脂有较长的防雾期;为获得好的防雾性,单体MAA(甲基丙烯酸)的加入应适量;复配引发体系中引发剂含量的增加延长了防雾期;交联抑制剂的加入改善了加工流动性和薄膜的外观;接枝的工艺条件,如接枝物的后处理、螺杆转速、挤出设备等也对薄膜的性能产生影响。 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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以硅烷(VTMS)、马来酸酐(MAH)为单体,过氧化二异丙苯(DCP)为引发剂,制备硅烷/马来酸酐接枝高密度聚乙烯(PE-HD),研究引发剂DCP、单体VTMS和MAH含量对接枝产物性能的影响,用红外光谱(FTIR)对接枝产物进行分析,并将接枝产物作为相容剂添加到复合材料中。结果显示:VTMS和MAH能够在PE-HD上进行接枝,随着DCP、VTMS和MAH含量的增加,接枝产物的接枝性能先增加后减小;和VTMS和MAH单种单体接枝PE-HD比较,硅烷/马来酸酐接枝高密度聚乙烯(MAH/VTMS -g-PE-HD)能够显著提高复合材料的力学性能。 相似文献
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改性PP的研究与应用 总被引:2,自引:0,他引:2
用马来酸酐(MAH)对聚丙烯(PP)进行接枝改性,制得改性PP膜。系统研究了反应温度、反应时间、引发剂(过氧化二苯甲酰)和单体(MAH)等对PP膜接枝率的影响。结果表明:改性后的PP膜性能得到提高。 相似文献
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采用固相接枝技术合成聚乙烯(PE)-马来酸酐(MAH)-甲基丙烯酸甲酯(MMA)-丙烯酸丁酯(BA)三元固相接枝共聚物,并利用傅立叶变换红外光谱分析了接枝聚合物的结构.考察了单体配比、单体总质量、引发剂过氧化二苯甲酰(BPO)、界面活性剂二甲苯和反应温度对接枝反应的影响.结果表明,MAH, MMA和BA三种单体都参与了固相接枝反应.接枝率随MAH和MMA用量的增加而增加,随BA用量的增加变化不大.引发剂BPO用量为聚乙烯质量的2 %时,接枝率最高;过量的界面活性剂不利于提高接枝率,适量的界面活性剂为聚乙烯质量的30 %;当BPO用量为聚乙烯质量的2%时,接枝共聚物的凝胶含量较高. 相似文献
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线性低密度聚乙烯反应挤出接枝马来酸酐的研究 总被引:8,自引:1,他引:8
以过氧化二异丙苯(DCP)为引发剂,在双螺杆挤出机中进行了马来酸酐(MAH)熔融接枝线性低密度聚乙烯(LLDPE)的研究,用红外光谱表征了接枝反应的存在。考察了引发剂用量、单体用量、螺杆转速以及温度对接枝反应的影响,并探讨了苯乙烯(St)作共单体对接枝反应的影响。研究表明:在引发剂含量较低时,用苯乙烯作共单体能够显著提高接枝率。 相似文献
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研究了淀粉与苯乙烯 (St)、甲基丙烯酸甲酯 (MMA)的接枝聚合反应。以焦磷酸锰 [Mn(H2 P2 O7) 3 ]3 -为引发剂 ,以十二烷基苯磺酸钠为乳化剂 ,考察引发剂浓度、反应温度、单体浓度对原位聚合反应中单体的转化率(X % )、接枝率 (G % )、接枝效率 (GE % )的影响。实验结果表明最高接枝率可达到 5 2 .4 % ,接枝效率可达 77.2 %。 相似文献
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The thermal radical curing of four diallylic monomers were studied and was found to be very similar. Dynamic DSC of diallyl orthophthalate (DAOP) showed a strong correlation between the cure rate and the half life temperature of the initiator employed. The extent of allylic cure was found by DSC to be very dependent on the reactivity of the initiator due to a dead-end effect, and to rise towards a plateau value with increasing initiator levels. DAOP was blended with poly(vinyl chloride) (PVC) in various weight ratios by both solution and melt compounding. The compatibility between DAOP and PVC was analysed by measuring the glass transition temperatures of mixtures with dynamic mechanical thermal analysis which showed that DAOP monomer and PVC were fully miscible regardless of the composition. The cure rate of the DAOP/PVC blends was found by dynamic DSC and isothermal NIR to increase with higher levels of PVC due to a gel effect accentuated by grafting to the PVC, while the final extent of cure decreased because of topological constraints. 相似文献
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ABS/PP相容剂的制备及应用 总被引:5,自引:0,他引:5
利用Brabender挤出机和密炼机分别制备了PP熔融接枝物PP—g—MAH,并用化学滴定法对接枝物的接枝率进行了定量分析,讨论了熔融接枝PP过程中过氧化二异丙苯、马来酸酐的用量对接枝率的影响,对比了2种不同工艺对pp-g-MAH接枝率的影响,实验还研究了相容剂对共混物力学性能影响。结果表明,PP—g—MAH的加入,在一定程度上改善了共混物的冲击性能、加工流动性和耐热性能。 相似文献
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纤维素醚的乳接枝共聚合 总被引:1,自引:0,他引:1
在水溶性聚合物羟丙基甲基纤维素(HPMC0存在下进行丙烯酸酯的乳液支共聚合,研究了引发剂加料方式,用量和HPMC用量对接枝率的影响,结果表明,引发剂质量分数和引发与纤维素的预接触时间对接枝率有显著影响,增大HPMC质量分数导致表观接枝率和真实接枝率明显下降。 相似文献
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通过偶联接枝技术,用硅烷偶联剂对纳米SiO2胶体和苯乙烯丙烯酸乳液进行了有机无机复合,制备了纳米SiO2改性苯丙复合乳液。采用正交试验法研究了复合乳液、填料和添加剂最优配比,分析了它们影响作用。通过试验考察了复合涂料的耐擦洗、附着力、老化和耐沾污等主要性能。结果表明:通过正交试验优选出的最佳涂料配方为14号配方,具体添加量:A为32%、B为2.5%、C为7.8%、D为7.8%、E为13%、F为3.9%、G为0.78%;复合涂料的附着力可达100%,耐洗刷次数可达22 576次,遮盖力为351.675 g/m2,耐沾污性可达95.8%。 相似文献
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Graft copolymerization of acrylonitrile onto bagasse and wood pulps has been studied using ceric ammonium nitrate as initiator. The effect of order of reactants addition on grafting was examined: three methods were studied. Addition of the pulp to a mixture of initiator and monomer (method A) resulted in more efficient grafting than the other two methods. The reaction produced more grafting at 50°C than at 30°C or at 40°C. The results showed that the monomer and initiator concentrations are the major factors influencing the grafting rate of acrylonitrile. Increasing the acrylonitrile or initiator concentration was accompanied by a substantial increase in graft yields. Increasing the initiator concentration is more effective on polymerization rate than the increase in monomer concentration. The extent of grafting of this monomer can best be controlled by reaction time. Water swelling of pulps significantly affected the grafting rate of acrylonitrile as well as the ceric consumption during grafting. The reactivity of bagasse pulp towards grafting of acrylonitrile is higher than that of wood pulp due to a more open structure of cellulose in bagasse pulp as well as the presence of some lignin which accelerates grafting. Ceric consumption during grafting depends on the nature of the pulp as well as the monomer and initiator concentrations, time, temperature, and the method of grafting. More Ce(IV) is consumed during grafting than during oxidation of the pulps under identical reaction conditions, due to homopolymer formation which accompanied grafting. The ceric consumption by bagasse during grafting or oxidation is somewhat greater than that consumed by wood pulp under similar reaction conditions. 相似文献