Preparation Of Cellulose-based Electrospun Fiber Composite Membrane And Its Application To Promote Plant Wound Healing

Electrospinning is a simple and efficient preparation of polymer micro-nano fiber technology,with low cost of equipment and experiments,high fiber yield,the preparation of the fiber surface area is large,widely available and so on.In recent years,various biocompatible and biodegradable bio-based polymer electrospun fibers(such as cel ulose acetate(CA),ethyl cel ulose(EC),polylactic acid(PLA),collagen(Collagen)Has been prepared by electrostatic spinning technology,in the wound dressing,tissue engineering,drug release,energy applications and catalyst load and other fields have also been widely used.In this thesis,aiming at the problem of low graft survival rate and plant cal us,we have proposed a method to design a functional electrospun fiber membrane material with long-acting and controlled supply of exogenous hormones which can improve the survival rate of grafting by combining electrospinning technology and drug release controlled release technology for the first time.And for the existence of other problems in grafting,carried out a useful exploration.In the first part of the study,based on the practical needs of plant grafting,cel ulose acetate(CA)with good biocompatibility was selected as the substrate,and the polyurethane(PU)was compounded to achieve good biocompatibility Good mechanical properties.The morphology of the blended fibers,the physical and chemical properties of the fiber membranes,the mechanical properties,the hydrophobicity,the cytotoxicity of the plants and the in vitro drug release behavior were studied.The PU / CA blended fiber membranes not only improved the mechanical properties.The mechanical properties of the fibers also retain the good hydrophilicity and biocompatibility of CA.In addition,by adjusting the proportion of PU and CA can be achieved within a certain range of hydrophobic and slow-release behavior of the adjustment.PU / CA blended film has the advantages of excel ent mechanical properties,high drug loading rate and adjustable release behavior.The second part is based on coaxial electrospinning technology,and the PU-CA core-shell electrospun fiber membrane is used as the drug carrier.Then,the morphology of the fiber,the physical and chemical properties of the fiber membrane,the mechanical properties,the hydrophobicity and the plant cytotoxicity and so on.PU-CA coaxial electrospun fibers were smooth,homogeneous,hydrophilic and biocompatible with pure CA.The release behavior of PUCA coaxial electrospun fiber membranes was studied by in vitro drug release experiment s,Compared with PU / CA blended fiber membrane,in the drug release and short release cycle of the problem has been greatly improved;through plant cal us experiments and plant grafting experiments,PU-CA coaxial electrospinning has Promote plant cal us and improve the survival rate of plant grafting.For the plant grafting may occur in the infection of bacteria and other issues.In the third part of this paper,the contents of PU / CA blends were studied.The composites were characterized by strong antibacterial,excel ent mechanical properties and long-term effect.The mechanical properties,mechanical properties,hydrophobicity and plant cytotoxicity of the fiber were measured.The results showed that the addition of Ag @ GO was the same as that of Ag @ GO / PU / CA composite electrospun fiber membrane.Which greatly improves the mechanical properties of PU / CA.It effectively avoids the emergence of drug release and is expected to achieve the long-term controlled release of drugs.It enhances the antibacterial activity of single silver nanoparticles.In this thesis,three kinds of PU-AC composite electrospun fiber membranes were designed and fabricated by blending and coaxial electrospinning technology.The mechanical properties were excellent,the biocompatibility was good,efficient anti-bacterial advantages,to achieve the plant exogenous hormones of the efficient load,long-term release and adjustable release.