In this paper, statistical optimization method was used to optimize the flash-spinning process conditions. Ultra-high molecular weight polyethylene(UHMWPE) superfine fiber was fabricated by flash-spinning method using...In this paper, statistical optimization method was used to optimize the flash-spinning process conditions. Ultra-high molecular weight polyethylene(UHMWPE) superfine fiber was fabricated by flash-spinning method using UHMWPE as the fiber-forming polymer, 1, 2-dichloroethane as the main solvent. The important parameters of the flash-spinning were filtered by Plackett-Burman experimental design based on the single factor experiments. After determining the best regions of the fiber properties, the optimum level of the important parameters were determined by Box-Behnken design. The results of the design showed that the important parameters influencing on the properties of the flash-spinning fiber were spinning temperature, spinning pressure, and spinning solution concentration. The optimum technical parameters were: spinning temperature 186.4 ℃, spinning pressure 6.16 MPa, spinning solution concentration 3.06%. The highest combination property of the flash-spinning fiber was 86.39 under this condition.展开更多
Quasi-static and high strain rate compressive behaviors and failure mechanisms of hygrothermal treated ultra-high molecular weight polyethylene/polyurethane(UHMWPE/PU)composites have been studied in this paper.Firstly...Quasi-static and high strain rate compressive behaviors and failure mechanisms of hygrothermal treated ultra-high molecular weight polyethylene/polyurethane(UHMWPE/PU)composites have been studied in this paper.Firstly,the UHMWPE composites were immersed in water at 70℃.The out-ofplane compression test was then performed on the dry/wet state specimens at quasi-static states(0.001-0.01 s^(-1))and high strain rate states(800-2 400 s^(-1)).The split Hopkinson pressure bar(SHPB)was adopted in the dynamic tests and waveform shapers were used to smooth and control the incident pulse.The results show that there are two platforms for the water absorption curve of UHMWPE composites.The absorption of moisture reduces the quasi-static compressive strength of the material while initially increasing,then decreasing the dynamic compressive strength.Matrix plasticization,fiber/matrix interface degradation and void expansion are the main factors affecting the irregular change of static/dynamic compressive strength of UHMWPE composites.展开更多
Ultra-high molecular weight polyethylene (UHMWPE) was blended with polypropylene (PP) in order to ensure good processing. Inorganic rigid particles were also used to toughen UHMWPE/PP blends. CaCO3 and a compound addi...Ultra-high molecular weight polyethylene (UHMWPE) was blended with polypropylene (PP) in order to ensure good processing. Inorganic rigid particles were also used to toughen UHMWPE/PP blends. CaCO3 and a compound additive containing heat mixed polyethylene glycol 2000 and white diatomite were added to the blends. The crystalline, surface morphology and mechanical properties of the blends were investigated comprehensively. The toughness of the material is effectively improved. By contrast, the compound additive had a better result. When the content of additive was 15%, the elongation at the break increased by 279.2% and the fracture energy increased by 343.8% compared to the original samples.展开更多
基金Key Project of Chinese Ministry of Education( No. 208005)Instructional Technology Project of National Textile andApparel Council, China ( No.2009076)Application Fundamental and Advanced Technology Research Proposal Project of Tianjin, China(No.10 JCYBJC03100)
文摘In this paper, statistical optimization method was used to optimize the flash-spinning process conditions. Ultra-high molecular weight polyethylene(UHMWPE) superfine fiber was fabricated by flash-spinning method using UHMWPE as the fiber-forming polymer, 1, 2-dichloroethane as the main solvent. The important parameters of the flash-spinning were filtered by Plackett-Burman experimental design based on the single factor experiments. After determining the best regions of the fiber properties, the optimum level of the important parameters were determined by Box-Behnken design. The results of the design showed that the important parameters influencing on the properties of the flash-spinning fiber were spinning temperature, spinning pressure, and spinning solution concentration. The optimum technical parameters were: spinning temperature 186.4 ℃, spinning pressure 6.16 MPa, spinning solution concentration 3.06%. The highest combination property of the flash-spinning fiber was 86.39 under this condition.
基金Supported by the Ministerial Level Advanced Research Foundation(2030301020502)
文摘Quasi-static and high strain rate compressive behaviors and failure mechanisms of hygrothermal treated ultra-high molecular weight polyethylene/polyurethane(UHMWPE/PU)composites have been studied in this paper.Firstly,the UHMWPE composites were immersed in water at 70℃.The out-ofplane compression test was then performed on the dry/wet state specimens at quasi-static states(0.001-0.01 s^(-1))and high strain rate states(800-2 400 s^(-1)).The split Hopkinson pressure bar(SHPB)was adopted in the dynamic tests and waveform shapers were used to smooth and control the incident pulse.The results show that there are two platforms for the water absorption curve of UHMWPE composites.The absorption of moisture reduces the quasi-static compressive strength of the material while initially increasing,then decreasing the dynamic compressive strength.Matrix plasticization,fiber/matrix interface degradation and void expansion are the main factors affecting the irregular change of static/dynamic compressive strength of UHMWPE composites.
文摘Ultra-high molecular weight polyethylene (UHMWPE) was blended with polypropylene (PP) in order to ensure good processing. Inorganic rigid particles were also used to toughen UHMWPE/PP blends. CaCO3 and a compound additive containing heat mixed polyethylene glycol 2000 and white diatomite were added to the blends. The crystalline, surface morphology and mechanical properties of the blends were investigated comprehensively. The toughness of the material is effectively improved. By contrast, the compound additive had a better result. When the content of additive was 15%, the elongation at the break increased by 279.2% and the fracture energy increased by 343.8% compared to the original samples.
