Inhomogeneity Reinforcement Structural Design And Mechanical Properties Of Thermoplastic Composite

Glass fibers and inorganic filler are two most longtime and general using reinforcement in thermoplastic composites. However, there is few research on inhomogeneity reinforcement structural design and its mechanical properties of thermoplastic composites. From composite interior construct perspective, the thermoplastic composities with high performance and low cost are designed and prepared containing inhomogeneity reinforcement spatial distribution in this thesis.The filler/glass fiber-mesh/glass fiber-mat reinforced PP composites with inhomogeneity reinforcement distribution was prepared by double belt press through melt-impregnation method. The influence of glass fiber and inorganic filler spatial distribution to the composite performance was studied and the mechanism of higher properties was researched also. The results show that distribution structure of glass fiber can be completed by one-step method, while filler distribution by two-step method. There is obvious influence of glass fiber distribution to mechanical performance, and the optimum construct is glass fiber-mesh in the outer with continunus mat in the middle of composites. Compared with GMT, the tensile strength and modulus increase by 59% and 53%, up to 161.59MPa and 8133.8MPa; the flexural strength and modulus increase by 42.1% and 36.8% respectively, up to 167.63MPa and 6997.5MPa; the impact strength increase by 37.2%, up to 107.24KJ/m2. There is close relationship between composite performance and the loading of glass fiber-mesh in fiber reinforcement and the optimum content is 40%(wt). The fiber bundle number of warp/weft of the mesh have no significant effect on the tensile and the bending properties of composites, but have obvious influence on toughness. The filler distribution influenced mechanical performance dramatically. When the filler works as the outer surface, it brings negetive effects to mechanical performance, on the other hand, when it is in the middle, it plays a positive role in the bending performance but not obvious effects in tensile and impact properties. Filler inhomogeneity distribution is more efficient to improve composite performance than filler uniformity distribution. Mechanical properties decreased with the increase of filler and an optimum ratio was given.