Study On The Preparation And Characterization Of Gel-spun UHMWPE/UHMWPP Composite Fiber

Ultrahigh molecular weight polyethylene(UHMWPE) fiber has plenty of excellent properties and has been used widely in the fields of military protection,ocean engineering and other special areas.But UHMWPE fiber exists some weakness,such as easy to creep under tension,poor heat resistance and poor processability which constraint its further application greatly.The ultrahigh molecular weight polypropylene(UHMWPP) and UHMWPE are both flexible chain polymers.They have similar polarity, solubility parameter and density,and PP has superior performance such as excellent creep resistance,higher temperature resistance and good adhesion property.Therefore with the modification by UHMWPP, UHMWPE fiber will have more outstanding performance.In this paper,the UHMWPE/UHMWPP composite fiber was prepared by gel spinning process.Different test apparatus were used to characterize the UHMWPE/UHMWPP composite fiber.The conclusions were as follows.1.The rheology studies on UHMWPE and UHMWPE/UHMWPP gels showed that the viscosity was reduced with the adding of UHMWPP,and the process behavior of UHMWPE could therefore be improved.When the temperature is 180℃,the gel system with 5wt%UHMWPP presents the best comprehensive performance:lower apparent viscosity,structural viscosity index and higher non-Newtonian index.2.Structure and morphology of extracted UHMWPE/UHMWPP composite fibers demonstrated that the typical "towel gourd tendon like"structure of UHMWPE was changed into a special "bamboo like" structure when 5wt%UHMWPP was added and typical "noodle like" structure for 10wt%UHMWPP.3.DSC and WAXD results indicated that the crystallinity was decreased by the adding of UHMWPP into UHMWPE matrix.4.The results derived from mechanical tests on HMWPE/UHMWPP composite fibers indicated that the creep-resistance and heat-resistance behavior were improved significantly with the increase of UHMWPP content.