Preparation And Performance Of Cellulose Acetate/?-Poly(Glutamic Acid) Electrospun Fibrous Membranes

Electrospinning is a kind of technology for preparing polymer nanofibers.Its simple equipment,easy operation,high fiber yield,has great advantages in application.In recent years,with the development of nanotechnology,nanofibers have applications in drug release,filter materials,protective materials,optoelectronic materials,and other fields.It has attracted widespread attention from researchers.For the first time,this paper combines electrospinning technology with plant growth to design a new type of functional electrospun composite fiber membrane that is beneficial to plant growth.This article uses electrospinning technology,based on the needs of plant growth,chooses cellulose fiber with good biocompatibility as the matrix material.By adding?-polyglutamic acid to cellulose acetate,Cellulose acetate/?-polyglutamic acid blended fiber membranes were prepared.After that,the cellulose acetate/?-polyglutamic acid blended fiber membrane is functionalized by adding nanoparticles.The effects of the polymer composition and the number of nanoparticles added on the fiber surface morphology,chemical composition,performance,and plant growth were studied.Research work is mainly divided into the following sections:First,we blended Cellulose Acetate?CA?and?-Poly?glutamic acid???-PGA?in acetic acid/H₂O?v:v=7:3?with different ratios.The properties of CA/?-PGA blended fiber membranes were characterized by scanning electron microscopy?SEM?,single fiber strength machine,Fourier transform infrared spectrometer?FTIR?,surface contact angle analyzer,differential scanning calorimeter?DSC?and thermogravimetric analyzer?TGA?.The proportion of cellulose acetate and?-Poly?glutamic acid?not only affects the morphology and diameter of the fiber,but also affects the hydrophilicity,mechanical properties and thermal properties of the fiber.The optimum spinning conditions were finally determined:the mass fraction of the solution was 10%,the mass ratio of CA/?-PGA was 7/3,and the voltage was 20 kV.After that,TiO₂ nanoparticles and ZnO nanoparticles were added into the CA/?-PGA electrospinning liquid by the blending method.TiO₂-CA/?-PGA fiber membranes and ZnO-CA/?-PGA fiber membranes were prepared by electrospinning at different mass fractions.The morphology of the fiber,the physical and chemical properties of the fiber membrane,mechanical properties,hydrophilicity and hydrophobicity,and thermal properties were tested.Using corn as experimental material,the effect of TiO₂-CA/?-PGA fiber membrane and ZnO-CA/?-PGA fiber membrane on plant growth was investigated by measuring plant height,leaf area and leaf SPAD value.The test results show that the fiber diameters of TiO₂-CA/?-PGA fiber membranes prepared by electrospinning are mainly distributed between 640-660nm.With the addition of Ti O₂,the mechanical properties of TiO₂-CA/?-PGA fibers are gradually improved,and the thermal stability is also improved.The fiber diameter of ZnO-CA/?-PGA fibers is mainly distributed between 460-540 nm.With the addition of ZnO,the mechanical properties of ZnO-CA/?-PGA fibers are gradually improved.The DSC test found that with the increase of the mass fraction of nanoparticles,the glass transition temperature of the material increases.The results of plant growth tests showed that corn seedlings treated with Ti O₂-CA/?-PGA fiber membrane and ZnO-CA/?-PGA fiber membrane could promote corn growth.In this dissertation,TiO₂-CA/?-PGA fiber membranes and ZnO-CA/?-PGA fiber membranes were designed and prepared by electrospinning technology.It was first proposed that electrospinning membranes could be used to promote plant growth,which broadened the application of electrospun fiber membranes in the field of plants.It provides a reference for the development of Nano-fertilizers,Nano-bionics,and Nano-pesticides.And there will be broad application prospects in the field of agricultural production.