Study on the in-situ synthesis and the crystallization, mechanical, dielectric properties of Polypropylene/Polybutene-1

Polymeric materials are widely used as capacitor diaphragm materials because of their good pressure resistance, low dielectric loss, good processing performance and good compatibility with devices. In this experiment, the Polypropylene/Polybutene-1 (PP/PB-1) resin was prepared by the reaction of butene-1 polymerization using the modified intermittent bulk polypropylene polymerization reactor. The structure and morphology of the prepared PP/PB-1were characterized by DSC, POM and FT-IR so on. The effects of different prepolymerization time on their crystalline morphology and mechanical properties were investigated. As the polypropylene prepolymerization time becomes longer, the content of Polypropylene in the synthesized polybutene-1 sample increased gradually, and the spherulitic size and nucleation time of polybutene-1 were changed. In addition, the tensile properties of the product were also improved. The PP/PB-1 film was prepared by the film drawing machine using synchronous biaxial stretching method. It was found that when the tensile temperature was 130°C and the tensile rate was 40mm / min, the prepared PP/PB-1 films had the best dielectric properties. At this time, the dielectric constant was 2.9, and the dielectric loss tangent was low (<0.005).