Preparation and characterization of novel ultra-high molecular weight polyethylene composite fibers filled with nanosilica particles

摘要

Ultrahigh molecular weight polyethylene (UHMWPE)anosilica (F2S_y) and UHMWPE/modified nanosilica (F2S_(mx-y)) as-prepared fibers were prepared by spinning of F2S_y and F2S_(mx-y) gel solutions, respectively. Modified nanosilica particles were prepared by grafting maleic anhydride grafted polyethylenes onto nanosilica particles. The achievable draw ratios (D_(ra)) of F2S_y and F2S_(mx-y) as-prepared fibers approached a maximal value as the original and modified nanosilica contents reached corresponding optimum values; the maximal D_(ra) value obtained for F2S_(mx-y) as-prepared fiber specimens was significantly higher than that of the F2S_y as-prepared fiber specimens prepared at the optimum nanosilica content. The melting temperature and evaluated lamellar thickness values of F2S_y and F2S_(mx-y) as-prepared fiber series specimens decrease, but crystallinity values increase significantly, as their original and modified nanosilica contents respectively increase. Similar to the achievable drawing properties of the as-prepared fibers, the orientation factor, tensile strength (σ_f) and initial modulus (E) values of both drawn F2S_y and F2S_(mx-y) fiber series specimens with a fixed draw ratio reach a maximal value as the original and/or modified nanosilica contents approach the optimum values; the σ_f and e. values of the drawn F2S_(mx-y) fiber specimens are significantly higher than those of the corresponding drawn F2S_y fiber specimens prepared at the same draw ratios and nanosilica contents but without being modified. To understand the interesting ultradrawing, thermal, orientation and tensile properties of F2S_y and F2S_(mx-y) fiber specimens, Fourier transform infrared, specific surface area and transmission electron microscopy analyses of the original and modified nanosilica were performed in this study.