Preparation and characterization of fluorinated polypropylene by reactive extrusion with fluorinated acrylate

The fluorinated polypropylene (PP) was prepared by reactive extrusion, in which PP was grafted with fluorinated acrylate, acrylic acid 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluoro-nonyl ester (HFNAE). The Fourier transformed spectroscopy results confirmed the graft polymerization on PP backbone by the reactive extrusion. The surface tension of these polymer materials and the influence of HFNAE on the crystalline behavior had been investigated with static contact angles apparatus, wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC) and the polarized optical microscope (POM). The surface tension of fluorinated PP was found to be less than that of the untreated polypropylene. The results showed that the fluorinated acrylate (HFNAE) might induce β form crystals when being grafted into PP from the result of WAXD and DSC. The spherule configuration difference between PP and fluorinated PP could be observed with POM photos. The result from the isothermal crystallization kinetic analyses indicated that the speed of the forming nuclear for the regular PP was smaller than that of the fluorinated PP. In addition, the addition HFNAE improved impact strength and thermal stability of PP, but the tensile tension decreased slightly.