Research on Modification of Polypropylene by One-step Silane-grafting and Cross-linking Method

High-melt-strength polypropylene (PP) was prepared by one-step silane-grafting and partial cross-linking of regular polypropylene through reactive extrusion.The influences of the modification on the properties were investigated by determination in Fourier transformed infrared spectra,melt-flowing properties,gel content,crystallizing performance,mechanical and foaming properties.Due to the silane-grafting and cross-linking,the melt strength and viscosity increased,melt flowing rate decreased significantly and high gel percentage up to 48 % was obtained in the modified PP.After modifying,its crystallization rate decreased due to the cross-linking.The mechanical and foaming properties of PP were improved,high-quality foam was fabricated with the modified PP.