Study On Polypropylene Fiber Enhancing Polypropylene Resin

The enhanced modification of polypropylene (PP) has been one of the important researches of PP modification at home and abroad. In recent years, the enhanced modification of PP is becoming more and more extensive, mainly on using fiber reinforced PP. The fiber includes glass fiber and some plant fiber. These fibers can improve the strength of PP, but at the same time will reduce the toughness, which will affect the use of materials.The subject proposed to use polypropylene fiber self-reinforcing PP, with the aim of enhancing PP resin with polypropylene fiber, simultaneously maintaining the good toughness of polypropylene fiber/PP composites, and preparing a new fiber-reinforced PP material with excellent comprehensive properties. To our knowledge, the study of Polypropylene fiber reinforcing PP had not been reported. Therefore, the study of polypropylene fiber/PP composites had important theoretical and practical value.Using polypropylene fibers with different deniers (900D and 240D) as he reinforcement, the PP resin as the matrix, the mechanical properties of composites were studied. Firstly, the optimal temperature was determined, and then under conditions of the optimal temperature, the effect of fiber content on mechanical properties of composites was studied. Using PP with different molecular weight obtained by adding a certain amount of dicumyl peroxide (DCP) as the matrix, the effect of PP on the mechanical properties was studied with the Polypropylene fiber content of 15%. The effect of temperatures, Polypropylene fibers with various deniers and fiber content on the mechanical properties of composites was systematically studied. Using the scanning electron microscopy (SEM), the interfacial bonding and microstructure of composites were characterized.The study on mechanical properties of PP/polypropylene fiber composites showed that:the optimal temperature was 195℃, and at this temperature, with the fiber content increasing, the tensile strength increased first and then dropped, and the highest point was the amount of 15%, the tensile strength of polypropylene fiber/PP composites with 900D denier was 26.88MPa, while the 240D was 25.76MPa. The impact strength decreased slightly, but remained 400 J/m or more, still showed ductile fracture. With the addition of DCP, the melt flow rate (MFR) of PP increased, then under these conditions added 15% fiber content, the tensile strength showed increasing trend, the impact strength decreased slightly. The SEM images showed that:differences of interfacial bonding had a significant effect on the mechanical properties of polypropylene fiber/PP composites; good interfacial bonding would improve the mechanical properties.