纳米石墨微片协效阻燃EVA纳米复合材料的研究

发布时间：2018-05-22 16:36

本文选题：纳米石墨微片 + EVA　；参考：《哈尔滨理工大学》2015年硕士论文

【摘要】：乙烯-醋酸乙烯酯共聚物(EVA)由于易燃性而限制了其广泛的应用领域，填加无机阻燃剂氢氧化铝(ATH)虽然能够提供良好的阻燃性能，但是过多的填加量对复合材料的力学性能及加工性能非常不利。纳米石墨微片(GNP)具有大比表面积、高的热稳定性作为填料填加在高分子材料基体中，很少的填加量就能够提高材料的热稳定性及阻燃性能。GNP与ATH复合使用可能实现较少的填加量而提供复合材料高的阻燃性能。本论文以膨胀石墨为原料通过湿法球磨制备GNP，并采用直接沉淀法和球磨共混法对GNP进行改性。采用X-射线衍射(XRD)、拉曼光谱、扫描电子显微镜(SEM)、透射电子显微镜(TEM)研究了GNP及改性GNP的结构；以熔融共混法制备GNP/EVA及改性GNP/EVA复合材料，通过热重分析(TG)研究了复合材料的热降解行为，以拉伸强度和断裂伸长率评价了复合材料的拉伸性能，以体积电阻率评价了复合材料的电学性能；并以GNP及改性GNP与氢氧化铝(ATH)复合应用于阻燃EVA，研究GNP及改性GNP与ATH的协效阻燃作用。研究结果表明：采用湿法球磨成功制备出GNP，实现了Fe2O3、NiO、硅烷(KH560)、2-羧乙基苯基次膦酸(CEPPA)对GNP的改性；GNP及改性GNP在EVA中分散均匀，加入GNP和改性GNP后复合材料的热稳定性较EVA有所提升，，而力学性能却有所下降，添加1%GNP的纳米复合材料具有良好的绝缘性；GNP与ATH具有协效阻燃作用，能够提高复合材料的氧指数，并有利于提高复合材料的UL-94等级；改性GNP与ATH的协效作用还与负载的粒子有关，其中负载CEPPA、KH560的GNP与ATH的协效作用相对较强，对复合材料的阻燃性能提高较大；加入ATH后复合材料的拉伸性能降低了很多，而体积电阻率却提升了一个数量级。
[Abstract]:Ethylene vinyl acetate copolymer (EVA) has limited its wide application due to its flammability. Although the addition of inorganic flame retardant aluminum hydroxide (ATH) can provide good flame retardancy, However, too much filling is unfavorable to the mechanical properties and processing properties of the composites. The nano-graphite microchip GNPs have large specific surface area and high thermal stability, which are used as fillers to be added to the matrix of polymer materials. The thermal stability and flame retardancy of the composites can be improved by a small amount of filling. The composite use of GNP and ATH may achieve less filling and provide high flame retardancy of the composites. In this paper, expanded graphite was used as raw material to prepare GNP by wet ball milling, and the GNP was modified by direct precipitation method and ball milling blending method. The structure of GNP and modified GNP were studied by means of X-ray diffraction, Raman spectroscopy, scanning electron microscope (SEM) and transmission electron microscope (TEM), and GNP/EVA and modified GNP/EVA composites were prepared by melt blending method. The thermal degradation behavior of the composites was studied by thermogravimetric analysis (TG). The tensile properties of the composites were evaluated by tensile strength and elongation at break, and the electrical properties of the composites were evaluated by volume resistivity. The synergistic flame retardant effect of GNP and modified GNP and ATH was studied by using GNP and modified GNP and aluminum hydroxide. The results showed that the modified GNP and modified GNP were dispersed homogeneously in EVA, and the thermal stability of GNP and modified GNP composites was improved after adding GNP and modified GNP, the results showed that the modified GNP was successfully prepared by wet ball milling, and the modified GNP was homogenized by Fe _ 2O _ 3 / nio, silane KH _ 560 and 2-carboxyethyl phenyl phosphonic acid (CEPPA-CEPPA-Cepa). However, the mechanical properties of the nanocomposites decreased, and the nanocomposites with 1%GNP had good insulation and flame retardancy, which could improve the oxygen index of the composites and improve the UL-94 grade of the composites. The synergistic effect of modified GNP and ATH was also related to the loaded particles, in which the synergistic effect of GNP and ATH was relatively strong, and the flame retardancy of the composites was improved greatly, and the tensile properties of the composites decreased significantly after the addition of ATH. The volume resistivity increases by an order of magnitude.
【学位授予单位】：哈尔滨理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB33;O613.71

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