长玄武岩纤维增强尼龙6复合材料的研究
发布时间：2019-05-16 11:54
【摘要】：玄武岩纤维增强热塑性复合材料具有高强度、高模量、耐高温、可循环利用、环境适应性强等特点,广泛应用于汽车、航天、船舶等工业领域,可以达到节能降耗、绿色环保的目的。研究玄武岩纤维增强热塑性复合材料具有一定的现实意义。本文采用熔融浸渍拉挤工艺制备了长玄武岩纤维增强尼龙6(LBF/PA6)复合材料,通过研究不同浸渍模具、不同张紧力、不同模具温度下的浸渍效果,确定了制备LBF/PA6复合材料的最佳工艺参数,并对所制备的复合材料的力学性能、非等温结晶及熔融行为、晶体结构、结晶形态及界面形貌进行了研究。针对复合材料界面结合较弱的缺点,采用了两种方法对复合材料进行了界面改性,进一步研究了盐酸、硅烷偶联剂对复合材料界面的改进效果。对LBF/PA6复合材料的制备工艺参数研究表明,辊系组合浸渍模具制备的复合材料中的纤维的分散性最好,浸渍效果最佳。熔融浸渍过程中张紧力对复合材料的粒料浸渍效果有较大的影响,当张紧力为19N时,所得粒料的浸渍效果最佳。模具温度也是影响浸渍效果的重要因素,当模具温度为255℃时,所得复合材料粒料的浸渍效果最佳。长玄武岩纤维对PA6有明显的增强效果,当LBF/PA6复合材料中玄武岩纤维含量为40%时,复合材料的拉伸、弯曲和冲击强度分别提升了179.69%、178.42%和306.36%。动态力学分析(DMA)的结果表明,长玄武岩纤维的加入能提高LBF/PA6复合材料的储能模量和玻璃化转变温度。在高温下玄武岩纤维对复合材料储能模量的提高要明显高于低温下,且玄武岩纤维的加入能明显提高复合材料的热模量保留率,这预示着复合材料负荷变形温度的提高。长玄武岩纤维对PA6具有异相成核作用,使复合材料的结晶速度明显变快,同时又有阻碍链段运动的作用。当纤维含量较低时,成核作用占主导地位,使复合材料的T0和Tp升高;当纤维含量较高时,阻碍作用占主导地位,使复合材料的T0和Tp下降。非等温结晶后的熔融曲线和广角X射线衍射(WAXD)谱图表明,单纯PA6中只有α晶形成,而加入玄武岩纤维使PA6形成了α晶和γ晶两种不同的晶型,偏光显微镜(POM)结果表明玄武岩纤维使PA6基体的球晶尺寸减小,且沿着纤维表面生成了一层微小的柱状晶体,但这种柱状晶体的形成很不均匀。临界纤维长度的理论计算和复合材料的扫描电镜(SEM)照片表明,纤维与基体的界面黏结力较差,为此对复合材料的界面改善进行了探讨。盐酸和偶联剂处理纤维均能有效的改善LBF/PA6复合材料的界面。当盐酸浓度为10%,处理时间为1h时,拉伸强度和冲击强度分别比未处理提高了8.94%和23.02%。硅烷偶联剂能在纤维与基体间形成化学键,从而大幅度提高了复合材料的力学性能,其中KH550对复合材料的界面改善效果最好,使复合材料的拉伸强度和冲击强度分别提高了17.46%和30.52%。
[Abstract]:Basalt fiber reinforced thermoplastic composites have the characteristics of high strength, high modulus, high temperature resistance, recyclability and strong environmental adaptability. Basalt fiber reinforced thermoplastic composites are widely used in automobile, aerospace, shipping and other industrial fields, and can achieve energy saving and consumption reduction. The purpose of green environmental protection. It is of practical significance to study basalt fiber reinforced thermoplastic composites. In this paper, long basalt fiber reinforced nylon 6 (LBF/PA6) composites were prepared by melt impregnation and extrusion process. The impregnation effects of different dipping molds, different tensile forces and different die temperatures were studied. The optimum technological parameters for the preparation of LBF/PA6 composites were determined, and the mechanical properties, non-Isothermal crystallization and melting behavior, crystal structure, crystallization morphology and interface morphology of the composites were studied. In order to solve the problem of weak interfacial bonding of composites, two methods were used to modify the interface of composites, and the improvement effect of hydrochloric acid and Silane coupling agent on the interface of composites was further studied. The preparation process parameters of LBF/PA6 composites were studied. the results showed that the dispersion of the fibers was the best and the impregnation effect was the best among the composites prepared by roller combined dipping mould. The tensile force has a great influence on the impregnation effect of the composites during melt dipping. When the tensile force is 19N, the impregnation effect of the obtained particles is the best. Die temperature is also an important factor affecting the impregnation effect. When the die temperature is 255 鈩，
本文编号：2478258
[Abstract]:Basalt fiber reinforced thermoplastic composites have the characteristics of high strength, high modulus, high temperature resistance, recyclability and strong environmental adaptability. Basalt fiber reinforced thermoplastic composites are widely used in automobile, aerospace, shipping and other industrial fields, and can achieve energy saving and consumption reduction. The purpose of green environmental protection. It is of practical significance to study basalt fiber reinforced thermoplastic composites. In this paper, long basalt fiber reinforced nylon 6 (LBF/PA6) composites were prepared by melt impregnation and extrusion process. The impregnation effects of different dipping molds, different tensile forces and different die temperatures were studied. The optimum technological parameters for the preparation of LBF/PA6 composites were determined, and the mechanical properties, non-Isothermal crystallization and melting behavior, crystal structure, crystallization morphology and interface morphology of the composites were studied. In order to solve the problem of weak interfacial bonding of composites, two methods were used to modify the interface of composites, and the improvement effect of hydrochloric acid and Silane coupling agent on the interface of composites was further studied. The preparation process parameters of LBF/PA6 composites were studied. the results showed that the dispersion of the fibers was the best and the impregnation effect was the best among the composites prepared by roller combined dipping mould. The tensile force has a great influence on the impregnation effect of the composites during melt dipping. When the tensile force is 19N, the impregnation effect of the obtained particles is the best. Die temperature is also an important factor affecting the impregnation effect. When the die temperature is 255 鈩，
本文编号：2478258
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