| Continious basalt fiber(CBF) developed by Soviet scientists firstly is a kind of advanced green environment fiber that can be degradated to soil parent material,it has not only mechanical properties but also the advantage on the high temperature and corrosion resistance.To a certain extent,basalt fiber can be instead of glass fiber and carbon fiber as a reinforcement of composite.But similar as other high performance inorga-nic fibers,its disadvantages such as the surface inertness,low bonding strength with the matrix and interface compatibility limit the comprehen-sive properties of the composites.In view of the above questions, this paper took basalt fiber as reinforcement to prepare BF/PP (polypropylene) composite.The effect of molding process parameter on properties of com-posite was analysised, and the interfacial modification and crystallization were also investigated in this paper. The main research contents were as follows:1.Molding process has a great influence on the properties of the composite.The study used single factor experiment to investigate the effect of molding temperature, pressure, packing time and mass fraction of the fiber on the properties of basalt fiber reinforced polypropylene composites.The results of mechanical properties test showed that processing conditions have great impact on the performance of composites. The samples gained the best mechanical properties when the process conditions such as molding temperature, pressure, packing time, fiber weight were selected as190℃,10MPa,10min,30%, the tensile strength reached to194.667MPa,the flexural strength reached to44.714MPa.2. Since the preparation and processing of composites were subjected by human factors and environmental factors, and test fixture clamping degree was very difficult to maintain a consistent, the properties of the composite material have a certain chance.This study used the ANSYS finite element analysis software to simulate the preparation and tensile process of composite molding process, in order to verify the optimum reliability. Through the ANSYS finite element analysis we found the simulation results was the same as the actual situation.The maximum stress occured in the sample of the straight segment near the end of the specimen, and the simulation maximum stress for195.2MPa which was very close to the testing results(194.667MPa).That is to say, taking the best technology(190℃,10MPa,10min,30%) to prepare BF/PP composite was reliable.3. With the basalt fiber treated by the different concentrations and types of silane coupling agent,the effects of coupling agent treatment and fiber content on the mechanical properties of the composites were studied. In considering of the main factors of composites’material mechanical performance, combined with economic benefits, each square weight and other factors, the composites’tensile strength and flexural strength could increased by49.8%and10.8%when the KH550concentration was0.75%, the weight ratio of PP and basalt fibers was70:30.4. The study used the orthogonal test method to investigate the effect of the parameters of plasma modification on the properties of basalt fiber reinforced polypropylene composites.The results showed that:the tensile strength and flexural strength could increased by26.9%and12.5%when the vacuum degree,power,processing time and the fiber content were selected as20Pa,100W,5min,fiber content was30%.5. With the DSC, the BF/PP composites’crystallization properties were studied.The results showed that:in the BF/PP system,the addition of the fiber, coupling agent modification and plasma modification can also played the role as the the PP crystallization nucleating agent.It was good for the orderly arrangement of PP macromolecular,so PP’s heterogeneous nucleation accelerated and the crystallinity of PP also increased.But basalt fiber processed by suitable concentration of KH550had a greater effect on the crystallinity than that of plasma processing,and it had the same effect on the properties of the composites. |
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