Promotion of zeolite as dispersion support for properties improvement of α nucleating agent in polypropylene

The effects of a combined system consisting of zeolite13X (Z13X) and the α nucleating agent sodium 2,2′-methylene-bis(4,6-di-tertbutylphenyl)-phosphate (NA-11) on the mechanical and crystallization properties of polypropylene (iPP) were studied in detail. The results show that the addition of Z13X to iPP/NA-11 not only increases the mechanical properties of iPP, but also accelerates its crystallization. In particular, at a weight ratio of 4:6 NA-11/Z13X and at a total amount of 0.2 wt%, the tensile strength and flexural modulus of iPP/NA-11/Z13X reach 37.9 MPa and 1896 MPa, respectively, and the crystallization temperature of the iPP/NA-11/Z13X system is 130.2 °C. Furthermore, a comparison of POM and mapping photographs of iPP/NA-11/Z13X and iPP/NA-11 indicate that the presence of Z13X increases the dispersion of NA-11 via hydrogen bonding (as evidenced by FT-IR) and accelerates the crystallization rate. The combined system consisting of Z13X and NA-11, with a lower concentration of NA-11(0.08 wt%), exhibits a similar crystallization ability compared to that of only NA-11 (0.2 wt%).