The Study On Comparision Of Raw Materials And Creep Properties Of Ultra-High Molecular Weight Polyethylene Fiber

Although the high molecular weight polyethylene fiber was considered to be the first high-performance industrial fibers in China, preparation of UHMWPE fiber still exsited major technical problem. On the one hand, the overall performance of domestic raw materials, compared with imported raw materials, was still a gap, so the majority of UHMWPE fiber enterprises currently rely on imports of raw materials; On the other hand, there was also a gap between imported fibers and domestic fibers because of outdated production process. In re-cent years, creep properties of UHMWPE has been more and more important. Therefore, there is a theoretical and practical value to study on domestic and imported raw materials and creep properties of UHMWPE fibers.In the background, making use of the twin-screw extruder, UHMWPE gel fibers made from three different raw materials were prepared in the same gel-spinning process. The final UHMWPE products were manufactured after extracting, drying and hot drawing. In the experiment, the mechanical properties and morphological structure of raw materials and fibers were studied on by use of apparatuses such as Mastersizer2000,Differential Scanning Calo-rimetry(DSC) and Instron5969. The Purpose of research was to provide reference for manu-facturing UHMWPE fibers with domestic raw materials. The results showed that different particle size and molecular weight of raw materials influenced properties of its solution; The raw materials degraded and molecular weight decreased significantly in gel-spinning process, Spinning conditions influenced obviously the mechanical properties of fibers. In the present study conditions, the strength, modulus and creep resistance of fiber made form domestic raw materials are better than that from imported raw materials. At the same time, the molecular chains of UHMWPE fibers was crosslinked to improve its creep resistance after UV irradiation. Different stages of UHMWPE fibers were selected to modify by UV irradiation in experiment. In addition, soaking time in heptane,crosslinking agent concentration and irradiation time on the effect of cross-linked were investigated. Fou-rier transform infrared spectroscopy,scanning electron microscopy (SEM),Instron5969 and other testing equipments were used to test the structure and properties of fibers before and af-ter modification. The experimental results showed that the best soaking time in heptane for UHMWPE fiber was 48 hours; the most suitable UV irradiation time was 6min; Compared with the as-spun fiber and refined fiber, the cross-linking effect of gel fiber was the best in the same modified conditions. After cross-linking modification, breaking strength and elongation of UHMWPE fiber were decreased slightly, the elastic modulus and creep resistance were improved and the surface morphology of UHMWPE fiber also changed significantly.