GMA Graft Modification Polypropylene And Its Application

Mica(M)is an abundant,naturally occurring aluminum silicate mineral with fake six-party or diamond shape,layered,the type of the columnar crystal.It is expected to become a new generation of PP composite toughening and reinforcing the inorganic materials owing to the advantages such as high temperature resistance,high strength,good sliding,small thermal expansion coefficient.The surface modification methods of Mica and the development and status of the modification of PP composites have been reviewed detailedly in this paper.The research background and significance of this project were also introduced.The main purpose of this work is modification of Mica filling into PP preparation with more excellent comprehensive properties of composite materials,studying the relationship between structure and properties.The main contents are as follows:Grafted product PP-g-(GMA-g-St)was prepared with PP modified by Glycidyl methacrylate(GMA)and styrene(St).The optimum reaction conditions were: the amount of initiator DCP is 0.3%,the amount of monomer GMA is 4%,the ratio of GMA and St is 4:2,the reaction temperature is 170 ?.The MFR and MS of grafted product are 5.2 g·10min-1and 40.71 kPa·s respectively.Compared with the modification effects on Mica with silane coupling agent KH550 and KH570 respectively,M/PP composite was prepared by melting extrusion using the modified Mica as the inorganic filler.SEM microstructure shows that the layer spacing of Mica modified is clearly visible,the distribution is relatively uniform,the dispersion is also improved,it illustrates that silane coupling agent improves the microstructure of Mica in some degree.The FT-IR and TG results show that the surface of Mica modified with silane coupling agent KH550 appears hydroxyl dimers characteristic peaks,macromolecular organic matter weightless when it is burning,these show that KH550 modified Mica successfully.The best condition of the Mica modified by KH550.is determined through measuring the dispersity and activity index.M/PP composites were prepared via melt blending using modified Mica as dispersion phase and PP-g-(GMA-g-St)as compatibilizer.The results showed that the mechanical properties of M/PP-g-(GMA-g-St)/PP composites were best at the same content of M-KH550.The impact strength,tensile strength and flexural strength increase 132.86%,17.23% and 32.50% when the content of M-KH550 and PP-g-(GMA-g-St)were 15% and 10% respectively.The structure of impact section compact,the modified Mica particles evenly dispersed in PP matrix,and react with PP-g-(GMA-g-St)to improve the interfacial compatibility of PP.M-KH550 exhibit more excellent nucleation effect,interface bonding force promotes the crystallization of PP matrix,and crystallinity improves significantly.The melt flow rate(MFR)decreases,and vicat softening point increases,the thermal stability of the composite is better.