Nanometer materials include roughly nanoparticle,nanotube, nanowire, nanofiber, nanofilm and nanoblock, among which nanofiber is defined as material with nanometer-sized diameter and longer than 1 micron in length. Th...Nanometer materials include roughly nanoparticle,nanotube, nanowire, nanofiber, nanofilm and nanoblock, among which nanofiber is defined as material with nanometer-sized diameter and longer than 1 micron in length. The research development of polymer nanofibers, including manufacture methods and properties of some polymer nanofibers as well as their potential applications is reviewed.展开更多
According to the characters of poly-ether-ether-ketone (PEEK) plastic, the spinnerets with three kinds of different structure were designed. The effects of spinneret structure on the melt spinning conditions, melt flo...According to the characters of poly-ether-ether-ketone (PEEK) plastic, the spinnerets with three kinds of different structure were designed. The effects of spinneret structure on the melt spinning conditions, melt flow instability of the screw extrusion, and the performance of PEEK fibers were studied. The results show that the appropriate screw extrusion temperature is 370 385℃. The PEEK fibers extruded using the spinnerets with L/D=6, 8holes and 0.5mm in diameter have better performances. The performances of PEEK fibers are related to the dia- meter of the spinneret hole. Increasing the L/D value of the spinnerets can not always improve the surface quality and the performances of PEEK fibers. The extrusion pressure is about 50% of that of the spinneret with 12holes and 0.3mm in diameter.展开更多
Both electrospinning apparatus and their commercial products are extending their applications in a wide variety of fields.However,very limited reports can be found about how to implement an energy-saving process and i...Both electrospinning apparatus and their commercial products are extending their applications in a wide variety of fields.However,very limited reports can be found about how to implement an energy-saving process and in turn to reduce the production cost.In this paper,a brand-new type of coaxial spinneret with a solid core and its electrospinning methods are developed.A novel sort of medicated Eudragit/lipid hybrid nanofibers are generated for providing a colon-targeted sustained release of aspirin.A series of characterizations demonstrates that the as-prepared hybrid nanofibers have a fine linear morphology with the aspirin/lipid separated from the matrix Eudragit to form many tiny islands.In vitro dissolution tests exhibit that the hybrid nanofibers are able to effectively prevent the release of aspirin under an acid condition(8.7%±3.4%for the first two hours),whereas prolong the drug release time period under a neutral condition(99.7±4.2%at the seventh hour).The energy-saving mechanism is discussed in detail.The prepared aspirin-loaded hybrid nanofibers can be further transferred into an oral dosage form for potential application in countering COVID-19 in the future.展开更多
文摘Nanometer materials include roughly nanoparticle,nanotube, nanowire, nanofiber, nanofilm and nanoblock, among which nanofiber is defined as material with nanometer-sized diameter and longer than 1 micron in length. The research development of polymer nanofibers, including manufacture methods and properties of some polymer nanofibers as well as their potential applications is reviewed.
文摘According to the characters of poly-ether-ether-ketone (PEEK) plastic, the spinnerets with three kinds of different structure were designed. The effects of spinneret structure on the melt spinning conditions, melt flow instability of the screw extrusion, and the performance of PEEK fibers were studied. The results show that the appropriate screw extrusion temperature is 370 385℃. The PEEK fibers extruded using the spinnerets with L/D=6, 8holes and 0.5mm in diameter have better performances. The performances of PEEK fibers are related to the dia- meter of the spinneret hole. Increasing the L/D value of the spinnerets can not always improve the surface quality and the performances of PEEK fibers. The extrusion pressure is about 50% of that of the spinneret with 12holes and 0.3mm in diameter.
基金This study was supported by the Natural Science Foundation of Shanghai,China(No.20ZR1439000)the USST college student innovation projects,China(Nos.SH2020227&XJ2020376-2020378).
文摘Both electrospinning apparatus and their commercial products are extending their applications in a wide variety of fields.However,very limited reports can be found about how to implement an energy-saving process and in turn to reduce the production cost.In this paper,a brand-new type of coaxial spinneret with a solid core and its electrospinning methods are developed.A novel sort of medicated Eudragit/lipid hybrid nanofibers are generated for providing a colon-targeted sustained release of aspirin.A series of characterizations demonstrates that the as-prepared hybrid nanofibers have a fine linear morphology with the aspirin/lipid separated from the matrix Eudragit to form many tiny islands.In vitro dissolution tests exhibit that the hybrid nanofibers are able to effectively prevent the release of aspirin under an acid condition(8.7%±3.4%for the first two hours),whereas prolong the drug release time period under a neutral condition(99.7±4.2%at the seventh hour).The energy-saving mechanism is discussed in detail.The prepared aspirin-loaded hybrid nanofibers can be further transferred into an oral dosage form for potential application in countering COVID-19 in the future.
