Preparation And Application Of Electrospun Cellulose Dendritic Nanofibers

In recent years,with the depletion of non-renewable resources such as petroleum and coal,biomass materials have gradually entered the field of vision.As one of the most common and abundant reserves of polysaccharides in nature,cellulose is an extremely ideal green material due to inexhaustible,non-toxic,environmentally friendly and degradable.At the same time,cellulose nanofibers prepared by electrospinning technology have been applied in many aspects and have shown great advantages.This paper mainly uses cellulose acetate as raw material,through electrospinning technology to form processing,combined with biomimetic,physical doping and chemical methods to prepare functional cellulose tree-like nanofiber membrane,and carry out related application research,the main research content including the following aspects:(1)Using cellulose acetate(CA)as raw material,glacial acetic acid as solvent,and organic branched salt tetrabutylammonium chloride(TBAC)as additives,by adjusting the electrospinning process parameters and deacetylation treatment of sodium hydroxide solution,The cellulose nanofiber membrane with good tree-like morphology was successfully prepared.The diameter of the main fiber was mainly distributed at 100-500 nm,and the diameter of the branched fiber was 20-100 nm.The prepared fiber membrane had good hydrophilicity and resistance.Solvent and good mechanical properties,its tensile strength can reach 3.9 MPa;when the areal density is 0.81 g/cm2,its filtration efficiency can reach 98.37%,air resistance is only 115 Pa,showing good air filtration performance.(2)Based on the above research,the manganese dioxide doped tree-like cellulose nanofiber membrane was prepared by doping with manganese dioxide particles,and the carboxylated modified porous tree-like nanoparticle was successfully obtained by hydrothermal reaction of citric acid solution.The fiber membrane is applied to the adsorption performance of heavy metal ions.The results show that the carboxylated modified porous tree-like nanofiber membrane has both physical and chemical removal effects on copper ions(Cu2+).At a concentration of 200 mg/L,the adsorption capacity can reach 399.14 mg/g,and the recyclability is good.After 5 times of repeated use,the adsorption capacity of Cu2-can still reach 359.25 mg/g,and its adsorption behavior accords with the Langmuir isotherm adsorption model.(3)Using the excellent mechanical properties and high specific surface area of carbon nanotubes(CNTs),the CNTs modified cellulose tree-like nanofiber membrane was successfully prepared by the"internal doping-external grafting"double modification technology.Its dye adsorption characteristics.The results show that the introduction of CNTs significantly improves the mechanical properties and dye adsorption properties of cellulose tree-like nano-nano,and its tensile strength at break can reach 9.2 MPa.When the concentration of methylene blue(MB)reaches 25 mg/L,the adsorption capacity can reach 36.05 mg/g.