SGF/PP泡沫复合材料的发泡效果和力学性能

Foamed Results and Mechanical Properties of SGF/PP Foam Composites

用单螺杆挤出机及型内二步法发泡工艺制备了短玻璃纤维(Short glass fiber,SGF)增强聚丙烯(Polypropylene,PP)泡沫复合材料,研究了SGF的质量分数对泡沫复合材料的泡孔形貌、界面粘结和力学性能的影响。结果表明,SGF的引入提高了共混体系的熔体强度,能够获得泡径细小且分布均匀的闭孔结构;偶联剂的表面包覆改善了SGF与PP的相容性,显著增强了两者的界面结合;随着增强纤维的加入,SGF/PP泡沫复合材料的冲击韧度和抗弯强度均呈现先增后降的变化趋势,并在SGF的含量为20%时达到最大值;研究发现,适量的SGF在共混体系中分散均匀且与基体的界面结合和共混体系的发泡效果得到显著改善,决定了SGF/PP泡沫复合材料能够获得优异的力学性能。

The short glass fiber （SGF） reinforced polypropylene （PP） foam composites are prepared and the influences of mass fraction of SGF on the cellular morphologies, interfacial adhesion and mechanical properties of foam composites are investigated. Results indicate that the melt strength of co-blend is improved by addition of SGF, facilitating the formation of finer cell structure with the reduced cell size and the increased cell density. The interracial performance is enhanced owing to the improved compatibility between the matrix and SGF coated by coupling agent. With the increment of fibers, the impact toughness and the flexural strength of SGF/PP foam composites are increased first and then declined, and the peak values are both obtained when the mass fraction of SGF is up to 20%. Experimental data reveal that the mechanical properties of SGF/PP foam composites are improved by the well dispersion of SGF in the matrix and the enhanced SGF-PP interfacial adhesion combined with improved foamed results of co-blends.