Nation（a branched perfluorosulfonate ionomer）is a kind of functional polymer materialwhich can be processed to different forms for various uses,such as electrolytic membrane or sep-aration hollow fiber,by convention...Nation（a branched perfluorosulfonate ionomer）is a kind of functional polymer materialwhich can be processed to different forms for various uses,such as electrolytic membrane or sep-aration hollow fiber,by conventional melt processing methods.In order to optimize the pro-cessing conditions of the polymer,the rheological properties of Nation ionomer in capillary flowwere studied and the flow behaviors of the polymer melt were also investigated.The resultsshowed that the value of non-Newtonian Index for Nation melt is reached up to 0.92 at 250℃and the viscosity shear—rate dependence of the polymer melt is minimized at the same tempera-ture.The polymer melt has the values of activation energies(61.5 KJ/mol to 12.5 KJ/mol atthe shear rate 0.42 s<sup>-1</sup> to 140 s<sup>-1</sup>)which is much lower than conventional polymer melts,such aspolyethylene terephthalate,polyamides,polypropylene etc.and the suitable processing tempera-ture of Nation ionomer for hollow fibres was proposed in the work.展开更多
A theoretical numerical communication is demonstrated to analyze the impact of Arrhenius activation energy and melting phenomena on chemically reactive Falkner-Skan flow of cross nanofluid over a moving wedge with vis...A theoretical numerical communication is demonstrated to analyze the impact of Arrhenius activation energy and melting phenomena on chemically reactive Falkner-Skan flow of cross nanofluid over a moving wedge with viscous dissipation and nonlinear radiation impacts.The basic partial differential equations for nanoparticle concentration,energy,momentum and mass conservation are reduced to nonlinear ordinary differential equations with the help of appropriate transforming variables and then solved numerically via bvp4c Matlab solver.It is interesting to notice that nanoparticle concentration and concentration boundary layer thickness are uplifted for enhancing values of activation energy parameter.Additionally,magnitude of heat transfer rate is a growing function of the Eckert number.展开更多
以EPDM g MAH为增容剂 ,采用熔融共混技术制备了热塑性聚氨酯弹性体 (TPU)增韧聚丙烯 (PP)材料 ,研究了PP/EPDM g MAH/TPU共混物的流变行为 ,重点讨论了增容剂EPDM g MAH对共混物流变行为的影响。结果表明 :共混物熔体的非牛顿指数n <...以EPDM g MAH为增容剂 ,采用熔融共混技术制备了热塑性聚氨酯弹性体 (TPU)增韧聚丙烯 (PP)材料 ,研究了PP/EPDM g MAH/TPU共混物的流变行为 ,重点讨论了增容剂EPDM g MAH对共混物流变行为的影响。结果表明 :共混物熔体的非牛顿指数n <1,且随EPDM g MAH用量的增加而减小 ,表观粘度随剪切速率和剪切应力的增大而降低 ,熔体符合假塑性流体的流动规律 ;温度升高 ,表观粘度降低 ;随着EPDM g MAH用量的增加 ,共混物的表观粘度升高 。展开更多
文摘Nation（a branched perfluorosulfonate ionomer）is a kind of functional polymer materialwhich can be processed to different forms for various uses,such as electrolytic membrane or sep-aration hollow fiber,by conventional melt processing methods.In order to optimize the pro-cessing conditions of the polymer,the rheological properties of Nation ionomer in capillary flowwere studied and the flow behaviors of the polymer melt were also investigated.The resultsshowed that the value of non-Newtonian Index for Nation melt is reached up to 0.92 at 250℃and the viscosity shear—rate dependence of the polymer melt is minimized at the same tempera-ture.The polymer melt has the values of activation energies(61.5 KJ/mol to 12.5 KJ/mol atthe shear rate 0.42 s<sup>-1</sup> to 140 s<sup>-1</sup>)which is much lower than conventional polymer melts,such aspolyethylene terephthalate,polyamides,polypropylene etc.and the suitable processing tempera-ture of Nation ionomer for hollow fibres was proposed in the work.
文摘A theoretical numerical communication is demonstrated to analyze the impact of Arrhenius activation energy and melting phenomena on chemically reactive Falkner-Skan flow of cross nanofluid over a moving wedge with viscous dissipation and nonlinear radiation impacts.The basic partial differential equations for nanoparticle concentration,energy,momentum and mass conservation are reduced to nonlinear ordinary differential equations with the help of appropriate transforming variables and then solved numerically via bvp4c Matlab solver.It is interesting to notice that nanoparticle concentration and concentration boundary layer thickness are uplifted for enhancing values of activation energy parameter.Additionally,magnitude of heat transfer rate is a growing function of the Eckert number.
文摘以EPDM g MAH为增容剂 ,采用熔融共混技术制备了热塑性聚氨酯弹性体 (TPU)增韧聚丙烯 (PP)材料 ,研究了PP/EPDM g MAH/TPU共混物的流变行为 ,重点讨论了增容剂EPDM g MAH对共混物流变行为的影响。结果表明 :共混物熔体的非牛顿指数n <1,且随EPDM g MAH用量的增加而减小 ,表观粘度随剪切速率和剪切应力的增大而降低 ,熔体符合假塑性流体的流动规律 ;温度升高 ,表观粘度降低 ;随着EPDM g MAH用量的增加 ,共混物的表观粘度升高 。
