The Manipulation Of Cellulose Electrospinning And Its Functionalization

Electrospinning is a technology for fabricating one-dimensional nanomaterials,and its product are widely used in many field,such as nanoelectronic device,sensor,support of catalyst,biomedical,and so on.Recently,the application of electrospinning has been focused from the preparation of different polymer nanofibers to the preparation of functional nanofiber composites.As a abundant natural polymer,cellulose has the properties of abundant,easy-degradation,bio-compatibility and so on.If it could be prepared in the form of ultra-fine fibers using electrospinning,and be functioned.Firstly,Cellulose nanofibers have been successfully fabricated by electrospinning of cellulose/LiCl-DMAc solutions manipulated by nonsolvents.Dimethylacetamide（DMAc）and dimethyl formamide（DMF）were used to manipulate the concentrated cellulose solution as the nonsolvents.Addition of nonsolvents was beneficial to increase the electrospinnable concentration of cellulose solution and obtain well-distributed nanofibers.The reason for the improvement in electrospinnable concentration was that the addition of nonsolvents could decrease the viscosity of cellulose solution.The morphology of electrospun cellulose nanofibers was related to the conductivity of solution,the interaction between cellulose and solvents,and the stability of cellulose solution during electrospinning.Secondly,cellulose-Ag@AgCl composites have been directly fabricated by electrospinning of cellulose/LiCl/Dimethylacetamide（DMAc）solution with AgNO₃ under visible light.Addition of AgNO₃ was be beneficial to improve the electrospinnability of celllose solution,and modify the electrospun fibers.During the process of modification,AgCl was formed and then dissolved in cellulose solution.Moreover,AgCl was easily precipitated again when the jet encountered with water during electrospinning.In addition,AgCl was easily reduced under the irradiation of visible light resulting in the formation of Ag.The cellulose-Ag@AgCl composites has the photocatalytic properties of degradation of Methyl Orange（MO）under visible light,and the photocatalyst still exhibits good catalytic ability in the process of reuse.Finally,the cellulose-AgCl composites have been directly fabricated by electrospinning,and the addition of poly（vinylpyrrolidone）（PVP）was successfully used for manipulating the morphology of the composites.The experimental results indicated that PVP was able to improve the electrospinnability of cellulose due to its good electrospinnability,and also could control the morphology and dispersion of AgCl nanoparticles as a polymer surfactant.In addition,the antimicrobial activity was tested against the model microbes Escherichia coli（Gram-negative）and Staphylococcus aureus（Gram-positive）.The results indicated that cellulose-AgCl composites had a good antimicrobial performance.