Preparation And Application Of Two-Component Micro-nanofibers By Positive And Negative Conjugate Electrospinning

Conjugate electrospinning(CE)is an electrospinning process with two opposite polarity power supplies.During CE process,the oppositely charged jets ejected from the two spinnerets and attracted each other,hold together,and the positive and negative charges neutralized.Along with the solvent evaporating and solidification,the electrospun fibers deposited on the collector.This method can be used to prepare two-components micro-nanofibers continuously,which overcomeing the limitation of materials in the two-component micro-nanofibers prepared by blend electrospinning and coaxial electrospinning.Two kinds of bicomponent micro/nanofiber membranes: thermoplastic polyurethane(TPU)/polyacrylonitrile(PAN),thermoplastic polyurethane(TPU)/polyvinylpyrrolidone(PVP)were prepared by CE process.The morphology,chemical composition and wettability of these two-component fiber membranes were examined.These results suggested that the two component fibers in the conjugated electrospun fiber membrane are cross-stacked,even some crimped fibers are formed due to the different properties of the bicomponent fibers.Moreover,the wettabity of the conjugated electrospun meshes is somewhere in between the two components fibrous meshes,which showed potential applications in drug delivery.The CE process was also used to study the two-component reaction-curing electrospinning mechanism.The oxidized component spinning precursor A containing the ethylene reactive monomer and the reducing component spinning precursor B are respectively connected to the positive and negative electrodes of the CE device.During the CE process,the opposite charged jets attracted each other and undergoing a chemical reaction to to form solidified fibers.Morphology and infrared spectroscopy characterization showed that the A component and the B component did undergo a redox curing reaction during the CE process,and forming fibers with several micrometers diameter,which may suggest a new curing mechanism in electrospinning.