The gel-spun ultra-high molecular weight polyethylene (UHMWPE) fibers were prepared at the industrial production line with different gel solution concentrations of 15 wt%, 18 wt% and 24 wt%. The difference in ultima...The gel-spun ultra-high molecular weight polyethylene (UHMWPE) fibers were prepared at the industrial production line with different gel solution concentrations of 15 wt%, 18 wt% and 24 wt%. The difference in ultimate structure and mechanical properties of UHMWPE fibers for different gel solution concentrations were analyzed by tensile testing, differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and small angle X-ray scattering (SAXS). With the increase of gel solution concentration, the ultimate mechanical properties of UHMWPE fibers were decreased and the crystallization and orientation of UHMWPE fibers became inferior. Besides, both the average shish length ( (Lshsh) ) and shish misorientation (B0) of UHMWPE fibers were decreased with the increase of gel solution concentration. In addition, the appropriate increase of spinning temperature led to the further optimization of the ultimate structure and mechanical properties of UHMWPE fibers.展开更多
The gelation properties of polyol acetal derivatives including 2,4-(3,4-dichlorobenzylidene)-D-sorbitol(DCBS), 1,3:2,4-di(3,4-dichlorobenzylidene)-D-sorbitol(DDCBS) and 1,3:2,5:4,6-tris(3,4-dichlorobenzyli...The gelation properties of polyol acetal derivatives including 2,4-(3,4-dichlorobenzylidene)-D-sorbitol(DCBS), 1,3:2,4-di(3,4-dichlorobenzylidene)-D-sorbitol(DDCBS) and 1,3:2,5:4,6-tris(3,4-dichlorobenzylidene)-D-mannitol(TDCBM) in 35 single solvents and 39 binary solvent mixtures have been studied. FTIR and XRD results suggest that the self-assembly patterns of the gelator will not change in either the single solvent component or the corresponding solvent mixtures, but the critical gelation concentration(CGC)will be influenced. The results of SEM and rheology showed that the formation of true gels at saturated concentrations. Improving the heating temperature may promote the dissolving of gelators which are even insoluble at the temperature of the solvent boiling point and change the gelation behaviors. FloryHuggins parameter(x) was used to predict the gelation behavior of DCBS in the mixed solvents, and it is shown that the x values for the mixed solvents that can be gelled by DCBS are either greater or smaller than those for the selected good solvents.展开更多
基金financially supported by the National Natural Science Foundation of China(No.51273210)Natural Science Foundation of Ningbo Municipal(No.2015A610021)K.C.Wong Magna Fund in Ningbo University
文摘The gel-spun ultra-high molecular weight polyethylene (UHMWPE) fibers were prepared at the industrial production line with different gel solution concentrations of 15 wt%, 18 wt% and 24 wt%. The difference in ultimate structure and mechanical properties of UHMWPE fibers for different gel solution concentrations were analyzed by tensile testing, differential scanning calorimetry (DSC), wide angle X-ray diffraction (WAXD) and small angle X-ray scattering (SAXS). With the increase of gel solution concentration, the ultimate mechanical properties of UHMWPE fibers were decreased and the crystallization and orientation of UHMWPE fibers became inferior. Besides, both the average shish length ( (Lshsh) ) and shish misorientation (B0) of UHMWPE fibers were decreased with the increase of gel solution concentration. In addition, the appropriate increase of spinning temperature led to the further optimization of the ultimate structure and mechanical properties of UHMWPE fibers.
基金the financial support of the National Natural Science Foundation of China(No. 21476164)Tianjin Science and Technology Innovation Platform Program(No. 14TXGCCX00017)
文摘The gelation properties of polyol acetal derivatives including 2,4-(3,4-dichlorobenzylidene)-D-sorbitol(DCBS), 1,3:2,4-di(3,4-dichlorobenzylidene)-D-sorbitol(DDCBS) and 1,3:2,5:4,6-tris(3,4-dichlorobenzylidene)-D-mannitol(TDCBM) in 35 single solvents and 39 binary solvent mixtures have been studied. FTIR and XRD results suggest that the self-assembly patterns of the gelator will not change in either the single solvent component or the corresponding solvent mixtures, but the critical gelation concentration(CGC)will be influenced. The results of SEM and rheology showed that the formation of true gels at saturated concentrations. Improving the heating temperature may promote the dissolving of gelators which are even insoluble at the temperature of the solvent boiling point and change the gelation behaviors. FloryHuggins parameter(x) was used to predict the gelation behavior of DCBS in the mixed solvents, and it is shown that the x values for the mixed solvents that can be gelled by DCBS are either greater or smaller than those for the selected good solvents.