共查询到16条相似文献,搜索用时 78 毫秒
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研究了复合交联剂、复合发泡剂及其用量对PP/EPDM复合材料力学性能的影响。实验结果表明:PP/EPDM(70∶30)复合材料经过微孔发泡后,其力学性能达到PP/EPDM(50∶50)复合材料力学性能;微孔发泡技术的应用可减少复合材料中EPDM用量,达到降低成本的目的。 相似文献
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不同聚丙烯材料共混的微孔发泡成型研究 总被引:2,自引:0,他引:2
聚丙烯(PP)熔体强度低,发泡性能差.将两种PP材料共混来改善PP的发泡性能,研究PP材料性质对共混体系微孔结构的影响.研究表明在各种发泡温度下使用纯PP材料很难制得泡孔结构好的微孔材料,而两种PP材料共混以后再进行微孔发泡,泡孔结构得到了改善.与两种相似熔点和黏度的PP共混材料相比,在高黏度的PP中混入少量的低熔点、低黏度PP时,可以制得泡孔结构更好的微孔材料.研究了共混比例对泡孔形态的影响,并从熔体黏弹性和结晶性能两方面分析了泡孔结构变化的机理. 相似文献
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HDPE共混PP微孔发泡技术研究进展 总被引:1,自引:1,他引:0
介绍了一种用高密度聚乙烯(HDPE)与聚丙烯(PP)共混以改善PP微孔结构的技术,对该技术的研究成果进行了综述性回顾。主要包括结晶度及加工条件对共混体系发泡性能的影响、HDPE熔体流动速率对PP/HDPE共混体系微孔结构的影响。共混发泡技术提高了PP的可发泡性,为解决PP发泡难的问题提供了新方法和新技术。 相似文献
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通过微发泡注射成型方法制备PP/EPDM(三元乙丙橡胶)/滑石粉复合材料制品,并研究滑石粉的含量对PP/EPDM/滑石粉微孔发泡复合材料的微观形态和力学性能的影响。结果表明:添加适量滑石粉的PP/EPDM/滑石粉复合材料的发泡效果优于仅添加单一的EPDM的PP/EPDM复合材料的发泡效果,而且当PP/EPDM/滑石粉的质量比为79/21/4时,微孔制品的微观形态最好;且此比例的PP/EPDM/滑石粉微孔发泡制品与未添加滑石粉的PP/EPDM微孔发泡复合材料制品相比,其拉伸强度、弯曲强度、冲击强度分别提高了2%、6%、4%。 相似文献
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采用PP与PE-HD共混的方法来改善PP的发泡性能,并从共混体系的熔体强度和结晶性能两个方面分析PE-HD含量对泡孔结构的影响机理。结果表明,PP/PE-HD共混体系的熔体强度随着PE-HD含量的增加先升高后减小,在含量为30%(质量分数,下同)时熔体强度最高。随着PE-HD含量的增加,共混体系中PP和PE-HD的熔点先升高后降低,PP的结晶度先减小后增大,而PE-HD的结晶度却逐渐增加。在含量为30%时,PP和PE-HD的熔点最高,PP的结晶度最小。PP与PE-HD共混以后,泡孔结构有了很大改善,且与熔体强度和结晶度相对应,泡孔结构在PE-HD含量为30%时最好。 相似文献
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Three different polyethylene/polypropylene (PE/PP) blends were microcellular foamed and their crystallinities and melt strengths were investigated. The relationship between crystallinity, melt strength, and cellular structure was studied. Experimental results showed that the three blends had similar variation patterns in respect of crystallinity, melt strength, and cellular structure, and these variation patterns were correlative for each blend. For all blends, the melt strength and PP melting point initially heightened and then lowered, the PP crystallinity first decreased, and then increased as the PE content increased. At PE content of 30%, the melt strength and PP melting point were highest and the PP crystallinity was least. The blend with lower PP crystallinity and higher melt strength had better cellular structure and broader microcellular foaming temperature range. So, three blends had best cellular structure at PE content of 30%. Furthermore, when compared with PE/homopolymer (hPP) blend, the PE/copolymer PP (cPP) blend had higher melt strength, better cellular structure, and wider microcellular foaming temperature range, so it was more suited to be microcellular foamed. Whereas LDPE/cPP blend had the broadest microcellular foaming temperature range because of its highest melt strength within three blends. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 4149–4159, 2007 相似文献
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In this study, the effects of batch processing conditions (foaming time and temperature) and blend composition as well as the effect of incorporating wood fiber into the blends on the crystallinity, sorption behavior of CO2, void fraction, and cellular morphology of microcellular foamed high‐density polyethylene (HDPE)/polypropylene (PP) blends and their composites with wood fiber were studied. Blending decreased the crystallinity of HDPE and PP and facilitated microcellular foam production in blend materials. The void fraction was strongly dependent on the processing conditions and on blend composition. Foamed samples with a high void fraction were not always microcellular. The addition of wood fiber inhibited microcellular foaming. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 2842–2850, 2003 相似文献