Preparation And Performance Research Of Glass Fiber/Wollastonite/POE/PP Composites

Polypropylene (PP) is an excellent thermoplastic with versatile application.However, its low mechnical strength, poor impact resistance and high brittle transformation temperature limit its further application.In order to prepare PP composites with high strength and toughness and excellent melt flow,ternary-components were adopted in this work to collaboratively modify PP. First of all, a new compatibilizer,silane-grafted PP(PP-g-Si) was prepared by melt-grafting. Various factors affecting grafting rate and melt flow were investigated. Compared the effect of compatibilization with PP-g-MAH, the appropriate amount of PP-g-Si was determined. Then the content of POE was fixed into the amount of 10% of PP. After mixing well the PP, POE, PP-g-Si and a variety content of GF, the GF/POE/PP ternary composites was prepared by melt-extrusion.Finally, the wollastonite was treated by surface-coupling KH-570 or NDZ-201. Based on the ternary composites, GF/wollastonite/POE/PP quadruple composites was fabricated by adding wollastonite into ternary composites with the aid of a two-screw extruder. Then the properties of the two composites were investigated comparably, such as mechnical properties, melt flow and crystallization features.The results showed that PP-g-Si had compatibilization effect on PP/GF and it improved both the tensile strength and toughness of PP/GF. Its compatibilization effect was better than that of PP-g-MAH. The addition of POE caused an substantial increase in notched impact strength, but the tensile and flexural strength slightly decreased compared with PP/GF. In addition, the presence of GF accerlerated the crystallization speed and increased the crystallization temperature. Treated by NDZ-201,the wollastonite had a higher activation index. After adding the treated wollastonite, the performances of quadruple composites were surerior to that of ternary composites. When the amount of PP-g-Si, GF and wollastonite, POE was about 20%,40%,10% and the ration of GF and wollastonite was 2:1, the composites showed optimal comprehensive properties that the strength of tensile, flexural and notched impact were 51.76Mpa,63.35Mpa and 8.42KJ-m-2, with the MFI of 6.475g-10min-1,66.96%,68%,171.6% and 181.5% greater than PP respectively.