Structures and Crystallization Behaviors of Transparent Polypropylene
The structures,crystallization morphologies and crystallization behaviors of the transparent polypropylene product RP340R produced by the chambroad polyolefin company and the imported similar product RP344RK were studied by the gel permeation chromatography(GPC),nuclear magnetic resonance(NMR),X-ray diffraction(XRD),polarized light microscope(PLM)and differential scanning calorimeter(DSC).The results indicate that the sequence structures of RP340R and RP344RK are similar.Both of them are random polypropylene copolymers containing a small amount of ethylene comonomer.Their crystal forms are α form and the spherulite sizes are obviously refined.With the increase of cooling rate,the initial crystallization temperature and the peak crystallization temperature decrease,but the crystallization rate increases.Compared with RP340R,RP344RK has a wider relative molecular mass distribution and a smaller activation energy of non-isothermal cold crystallization.
万方数据
维普
