| A series of novel laminar polyolefin with low surface energy and improved barrier properties were designed and prepared, where the fluorinated polypropylene with lower surface tension and excellent hydrophobicity and oleophobicity, is the disperse phase The fluorinated polypropylene could reduce the wettability of water and hydrocarbon solvent as well as the permeation rate of water and hydrocarbon solvent.At first, the novel fluorinated polypropylenes (FPP ) were prepared by reactive extrusion of polypropylene (PP) with fluorinated methacrylate, 2, 3, 4, 5, 5, 5-hexafluoro-2, 4-bis (trifluoromethyl) pentyl methacrylate (HFPMA) or acrylic acid 2,2,3,3,4,4,5,5,6,6,7,7,8,8,9,9-hexadecafluoro-nonyl ester (HFNAE), aiming at decreasing the surface energy of polypropylene. The surface properties of these polypropylene materials, the influence of HFPMA or HFNAE on the crystalline behavior and mechanical properties were investigated by the X-ray photoelectron spectroscopy (XPS),X-ray diffraction (XRD),differential scanning calorimeter(DSC),polarized optical microscope (POM),melt index measurement and universal tester, etc. The surface tension of FPP is found to be about near 20 mN/m while varying the fluorinated monomer contents, which was lower than that of the original PP (about 30 mN/m). The WAXD and DSC studies suggested that the grafting of the fluorinated acrylate onto the PP might induce the formation ofβform crystals, which is rarely found in the common PP materials, and there exited an mixed crystal structure for FPP-theα-form co-existed withβ-form. The impact strength and thermal stability of FPP were increased, but the tensile tension decreased slightly. In addition, there is existed a strong ultraviolet absorption peak at 210nm in ultraviolet absorption spectrum of HFPMA and HFNAE, which suggested that the FPP bottles showed better anti-ultraviolet transmittance properties than PP. Furthermore, novel barrier materials based on the lamellar blends of PP and FPP with low surface energy were prepared by laminar blends technology. The morphology of PP/FPP blends with different melt-shear-viscosity was studied by scanning electron microscopy (SEM) and optical microscope. The effects of the screw speed,die temperature and interface tension on the morphology of extruded ribbons were investigated. Laminar morphology of PP/ FPP blow-molded bottles was obtained by blow-molded process, for the first time. The result showed that for PP/FPP blends withηd/ηm>1, the clear laminar structure was developed. The permeation resistances of PP/FPP for water ,acetone and xylene are about 15.6 times, 4.7times and 2.1 times than original polypropylene bottles, respectively ,at 30℃At last, a new barrier model was advanced for fluorinated polyolefin barrier material with low surface energy. Some experiments were designed to confirm the new barrier model. The improvement of solvent permeation resistance can be account for the combination of increased tortuousity path and decreased capillary wettability. Many factors, such as the number of laminar, morphology (including the length and the width of laminar), the distance between layers, and the contact angle of solvents on the surface barrier layer, influenced the solvent barrier improvement (BI). BI value could be calculated by the theory formula as followed:...
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