writer：Xiao-sui Chen1,2,3, Sheng Zhang?1,2,3 , Guo-zhi Xu?4, Xin-jun Zhu5, Wei Liu1,2
keywords：Aramid fibers; Polypropylene; Reinforcement; Crystallization;
source：期刊
Issue time：2011年

This paper reports the mechanical and thermal properties together with the crystallization behaviour of pure PP and PP composites containing 5 wt%, 10 wt%, 20 wt%, 30 wt% and 40 wt% aramid fibers. The mechanical properties of samples were evaluated by the tensile and izod notched impact testings, and the results show that the tensile strength of the composites can reach up to 54 MPa, while the izod notched impact strength can be enhanced to 54 kJ/m². The structure and the morphology were observed by scanning electron microscopy (SEM) and polarized optical microscope (POM), and it has been demonstrated that a solid interface adhesion between the matrix and fibers can be formed. The thermal behaviour and crystallization of PP/AF composites were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC), and the results show that the char residue at700℃can be significantly improved by the presence of aramid fibers. The super-cooling degree (△T) and initial crystallization temperature (T_ic) and crystallization percentage (X_c) were used to characterize the crystallization of the composites, and the results suggest that aramid fibers has positive effects on promoting nucleation which can improve the mechanical properties of the composites.