加工温度对PP无纺布自增强复合材料性能的影响  

Effect of Processing Temperatures on the Properties of Nonwoven Self-reinforced Polypropylene Composites

作　　者：苑晓洁 蔡烨梦 陈旭 肖志远 孙树凯 马俊祥 Yuan Xiaojie;Cai Yemeng;Chen Xu;Xiao Zhiyuan;Sun Shukai;Ma Junxiang(AVIC Composite Co.,Ltd.,Beijing 101300,China;ACC(Beijing)Science and Technology Co.,Ltd.,Beijing 101300,China)

机构地区：[1]中航复合材料有限责任公司,北京101300 [2]中航复材(北京)科技有限公司,北京101300

出　　处：《工程塑料应用》2023年第8期84-91,共8页Engineering Plastics Application

摘　　要：为探究不同热压温度对PP熔喷无纺布(PPNWF)自增强复合材料结晶结构及力学性能的影响,将PPNWF作为预制体通过热压法成功制备了自增强的PP复合材料,并考察了在不同加工温度条件下制备得到试样的结构与性能的关系。扫描电子显微镜及拉伸测试表明,当加工温度保持在170℃或173℃时,复合材料内部纤维相及基体相之间能够形成较好的界面结合,且纤维相的含量也能维持在较高的水平,内部稳定的增强相在拉伸过程中对基体相的取向产生了显著的抑制,自增强复合材料综合性能优异。差示扫描量热分析及X射线衍射结果表明,随加工温度的进一步升高,材料中高结晶度及取向度的纤维相含量逐渐减少,复合材料总体结晶度下降,主要晶型由取向α晶型逐渐向各向同性α晶型转变,期间伴随少量β晶型的产生与消失。PPNWF中纤维相的熔点在较高加工温度及成型压力下会向高温方向移动,而在177℃及180℃成型的试样在145℃出现的小放热峰对应于β晶型的熔点。且自增强复合材料中基体相在拉伸测试过程中未产生明显取向,因而其在拉伸后的结晶度及晶型较完全熔融的试样能够得到较为良好的保持。To investigate the effect of different hot pressing temperatures on the crystal structure and mechanical properties of self-reinforced polypropylene melt-blown non-woven fabric(PPNWF)composites,PPNWF was used as a preform to successfully prepare self-reinforced polypropylene composites by hot-pressing,and the relationship between the structure and properties of the samples prepared at different processing temperatures was investigated.Scanning electron microscope and tensile properties tests show that the processing temperature is maintained at 170℃or 173℃,the internal fiber phase and the matrix phase of the composite can form a good interface combination,and the content of the fiber phase can also be maintained at a high level.The internal stable reinforcing phase significantly inhibite the orientation of the matrix phase during the stretching process,and the self-reinforcing composites show excellent comprehensive performance.The results of differential scanning calorimetry and X-ray diffraction show that with the further increase of processing temperature,the content of fiber phase with high crystallinity and orientation degree in the material decrease gradually.The overall crystallinity of the composites decreases,and the main crystal form transforms gradually from orientationαcrystal form to isotropic crystal form.During this period,there is a small amount ofβcrystal form formation and disappearance.The melting point of the fiber phase in PPNWF will move towards high processing temperatures at higher temperatures and forming pressures.The small exothermic peak observes at 145℃for samples molding at 177℃and 180℃correspond to the melting point ofβcrystal form.In addition,the matrix phase in the self-reinforced composites don't have obvious orientation during the tensile test,so its crystallinity and crystal form after stretching can be better maintained than that of the completely molten sample.

关 键 词：PP 自增强 复合材料 结晶结构 

分 类 号：TQ325.14[化学工程—合成树脂塑料工业]