Research On The Preparation And Properties Of Basalt Fiber Reinforced Polypropylene Composites

This thesis is based on polypropylene (PP) resin on a wide range of applications and the actual needs in the automotive, so studies on enhancement and toughening modification of polypropylene. Adopting new environmental friendly fiber material basalt fiber (BF) reinforced on polypropylene, using four types of elastomers which are styrene-ethylene-butylene-styrene (SEBS), ethylene-propylene-diene-terpolymer rubber (EPDM), polyolefin elastomer (POE), ethylene-vinyl acetate copolymer (EVA) toughening modified polypropylene, and by adding compatilizer (PP-g-MAH) to improve the compatibility between the two kinds of polymer.Through using the Melt blending method to prepare PP/BF composites, PP/PP-g-MAH/BF composites and PP/PP-g-MAH/Elastomer/BF composites. And then doing tensile and impact experiments for different content of BF in the same kind of composite material system and different components of composite materials. Observing fractographic features by scanning electron microscope (SEM) to research the mechanical properties of the composite system mechanism. Non-isothermal crystallization properties of the composites were analyzed by using differential scanning calorimetry (DSC). Studying the crystallization properties mechanism of the composite system by using the theory of crystallization kinetics. Using polarizing microscope (POM) to study spherulite growth situation and the spherulite morphology of the composites. Applicating X-ray diffraction (XRD) to study the crystal structure of the composite material. Studying the thermal weightlessness of composite by thermogravimetric experiments (TGA) and researching composite thermal stability.Through the mechanical performance study shows:The tensile properties of the PP/BF composite material increasing significantly with the increasing BF content. By contrast10%BF content of different components of the mechanical properties of composites shows:After addition elastomer and compatilizer the tensile and impact property is improved. The tensile strength is largest which contains EPDM and the impact strength is the best which includes POE.Through the performance of non-isothermal crystallization shows:With the cooling rate increases, the crystallization rate is increased, the crystallization temperature decreases, the melting temperature decreases. Compared to pure PP, the BF content can promote the crystalline properties of the composite, the crystallization temperature is increased, the crystallization rate is improved. Compatibilizer PP-g-MAH has little effect on crystalline properties of the composite system. The addition of elastomer promotes the crystallization performance. By POM pictures we can see,10%BF content of the composite material, elastomer promotes the nucleation of composite materials. EPDM and EVA promotes the crystallization performance significantly. They accelerate spherulite crystallization rate in unit time, accelerate the nucleation rate and spherulite fuzzy boundaries. As can be seen from the XRD curve, crystal structure of the composite materials has no obvious impact with addition of compatilizer and elastomer. With BF joining, composite system generates a tiny amounts of beta crystal. We can draw the conclusion from the TGA curves that elastomer enhanced composite material thermal stability. The heat-resisting of the composite material which includes EVA is the best. Elastomer EPDM is the second.