静电纺丝法制备高分子纳米纤维的成因研究(英文)

静电纺丝法制备高分子纳米纤维的成因研究(英文)Research on the mechanism of preparing polymer nanofibers by electrospinningI

() 静电纺丝法制备高分子纳米纤维的成因研究英文 Researchonthemechanismofpreparingpolymernanofibersby electrospinning Introduction Electrospinningisaversatileandefficienttechniqueforproducing polymericnanofiberswithdiametersrangingfromtensofnanometersto severalmicrons.Theelectrospinningprocessisbasedontheuseofanelectric fieldtostretchandelongateachargedpolymersolutionormelt,whichisthen collectedasafibrousmatonagroundedsubstrate.Thehighsurface area-to-volumeratiooftheresultingnanofibersmakesthemidealcandidates forawiderangeofapplications,includingtissueengineering,drugdelivery, andfiltration. Inthisstudy,weinvestigatethemechanismunderlyingthe electrospinningofpolymernanofibers.Specifically,wefocusontheroleof electrostaticforcesincontrollingthemorphologyanddimensionsofthe nanofibers,aswellasthefactorsthatinfluencetheformationandstabilityof theelectrospunjet. ElectrospinningMechanism Whenapolymersolutionormeltissubjectedtoahighvoltage,it becomeschargedandisattractedtowardthegroundedtarget.Asthejetof chargedpolymeriselectrostaticallystretched,itundergoesaseriesof instabilitiesthatleadtotheformationofaseriesofbeadsandfibers.The instabilityofthejetisduetotheinteractionofsurfacetensionforces,charge repulsion,andelectricfieldeffects.Thejetbreaksintodropletswhentheforce ofsurfacetensionovercomestheforceofelectrostaticattraction. Electrostaticforcesplayacriticalroleinelectrospinning,asthey determinethestretchingandelongationofthepolymersolution.Inparticular, surfacechargesonthepolymersolutionormeltcausetheformationofan electricfieldnearthesurface,whichinturninduceschargesonthesurfaceof thepolymerjet.Thechargesonthejetsurfaceinteractwiththeelectricfield andarerepelledfromeachother,causingthejettostretchandelongate. FactorsAffectingElectrospinning Severalfactorscanaffecttheelectrospinningprocess,includingthetype andconcentrationofpolymer,thesolventsystem,theelectricfieldstrength andthedistancebetweentheneedletipandthecollector.Theconcentration ofthepolymersolutionisacriticalfactor,asitdeterminestheviscosityand surfacetensionofthesolution,whichinturnaffectthemorphologyand diameteroftheresultingnanofibers.Ahigherconcentrationofpolymer solutioncanleadtotheformationofthickerandmoreirregularfibers,whilea lowerconcentrationmayleadtotheformationofthinner,moreuniform fibers.