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Polypropylene(PP) has excellent comprehensive performance, but at the same time, there are some defects, for instance, poor impact properties, low tensile strength, bad heat resistance and low transparaency, which have limited the range of application of PP to a large extent. Therefore, it is necessary to modify PP to improve the performance of it, and to expand its scope of application.There are considerable amount of research on polypropylene grafted by maleic anhydride.This paper investigated the integrated properties of polypropylene which was mixed with maleic anhydride derivatives (marked as GMA). The results showed that after addition of GMA, the polypropylene had lower crystallinity, bad heat resistance, and the the crystallization temperature and crystallization rate of PP had just increased a little. On the other hand, the addition of GMA increased the impact strength of PP, especially when the content of GMA was 0.5wt% , the impact strength increased 24.47 kJ/m2 than that of neat PP. However, the addition of GMA reduced the tensile strength and flexural strength of PP.Inoganic particles added to polypropylene to improve the performance of polypropylene have been reported in the literature. In this paper, after the study of the nucleation effect of GMA on PP, GMA was mixed with different inoganic particles, and then added to PP in order to investigate effects of inoganic particles on PP/GMA composite. The results showed that after the addition of mixture of GMA/inoganic paritcles, the crystallinity, crystallization temperature, crystallization rate and heat resistance of PP were improved, at the same time, impact strength and flexural strength of PP also improved a lot.Aβ-form nucleating agnet (marked as LG) was synthesized by my team. Based on this work, this paper investigated the performance of LG, and compared it with TMB-5. The results showed that LG was an effectiveβ-form nucleating agent. When the addition of LG was 0.15wt%, theβ-form PP in polypropylene can reach 93.1%. Comparing with TMB-5, LG upgrading the mechanical properties of PP was superior to TMB-5.This paper investigated twoβ-form nucleating agent/inoganic particles composites respectively. One composite is LG mixed with nano-CaCO3, nano-SiO2, 4A molecular sieve, 5A molecular sieve respectively, and the other one is TMB-5 mixed with nano-CaCO3, 4A molecular sieve, 5A molecular respectively. The results showed that after LG mixed with inoganic particles, it’s ability of inducing PP to formβ-phase PP declined rapidly. However, the addition of inoganic particles improved the the crystallization temperature, crystallinity, and crystallization rate of PP compared with the addition of neat LG. On the other hand, LG mixing with ingonaic particles reduced the impact strength, but improved tensile strength and flexural strength of PP. After TMB-5 mixing with inoganic particles, it’s ability of inducing PP to generateβ-phase PP also declined, however, the declining was not as much as that of LG. Comparing with the addition of neat TMB-5, the addition of TMB-5/inoganic particles also improved the crystallization temperature, crystallinity, and crystallization rate of PP, and increased the impact strength, tensile strength and flexural strength of PP.After the comprehensive comparing of LG/inoganic particles and TMB-5/inoganic particles, it turned out the stability of TMB-5 was better than that of LG when mixed with ingoanic particles.
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