石墨烯/聚丙烯纳米复合材料流变与拉伸性能

采用熔融共混法制备了多种粒径、不同含量的石墨烯(GNP)/聚丙烯(PP)纳米复合材料,通过流变实验和拉伸实验分别研究了GNP粒径和GNP含量对复合材料流变特性的影响以及注塑成型工艺参数(注塑温度、注射压力、注射速度及背压)对复合材料拉伸性能的影响。研究结果表明,GNP微粒能够显著改善PP基体的抗拉强度,在一定含量范围(3%~9%)和较大粒径(40μm)时,会对PP熔体的流动性产生较大影响。虽然,注塑成型工艺参数对GNP/PP复合材料的抗拉强度影响较小,但是,其对材料的韧性影响较大。随着注塑的温度、压力、速度和背压的升高,材料韧性呈先增后降的趋势,最优参数组合为注塑温度215℃、注射压力60 MPa、注射速度50%、背压压力1 MPa。

Rheologicaland Mechanical Properties of Polypropylene/Graphene Nanocomposite

Graphene(GNP)/polypropylene(PP)nanocomposites with different particle sizes and contents were prepared by melt blending.The effects of GNP particle size and GNP content on the rheological properties of the composite were studied by rheological experiments,and the influences of the injection molding parameters(injection temperature,injection pressure,injection velocity and back pressure)on the mechanical properties of the composite were also studied by tensile experiments.The results showed that GNP particles could significantly improve the tensile strength of PP matrix,and had a greater impact on the fluidity of PP melt in a certain content range(3%~9%)and a larger particle size(40μm);injection molding process parameters had a smaller impact on the tensile strength of GNP/PP composite,but had a greater impact on the toughness of the material.With the increase of molding temperature,injection pressure and speed,back pressure,the toughness of the material increases first and then decreases.The optimum combination of parameters was molding temperature215℃,injection pressure 60 MPa,injection speed 50%,back pressure 1 MPa.