Study On Preparation And Properties Of Chitosan/Poly (Ethylene Oxide) Electrospun Composite Membrance

As one kind of natural polymer, chitosan has good physical and chemical properties, great physical activity, favorable biocompatibility and biological degradability. Without harmful degradation products during antibacterial reaction with blood, chitosan can also promote wound healing and tissue regeneration.The PEO is also a kind of biological material with good biocompatibility and non-toxic. Moreover, it's no skin irritation Due to its excellent spinnability, the PEO can be used to spin with chitosan for improving the poor spinnablity of chitosan.In this study, nanofibers were fabricated by electrospinning the acetic acid(HAc) solution which contains cationic chitosan and neutral PEO. The morphology of chitosan/PEO nanofibers was investigated by scanning electron microscope (SEM). The molecular interaction between chitosan and PEO was investigated by Fourier transformed infrared spectroscopy (FT-IR), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The hydrophilicity of the electrospun fibers was investigated by FT-IR and contact angle (CA). The influence of solution parameters (such as the concentration of solution and solvent, the mass ratio of chitosan to PEO) and processing parameters(such as voltage, flow rate, temperature, the distance from tip to collector) on fibers'formulation and morphology was also discussed. The chitosan/PEO nanofiber membranes were treated by alkaline air (NH3) in low-temperature plasma and the results were compared with those not treated in low-temperature plasma.The main results were listed as follows:1. The chitosan/PEO fibers were prepared by electrospinning of chitosan/PEO aqueous HAc solution. The viscosity of solutions which were controlled by the concentration of solution and solvent, the mass ratio of chitosan to PEO could directly affect the spinnability of chitosan/PEO aqueous HAc solutions. And the favor solution parameters as below:the concentration of solution is 5%w/v, the mass ratio of chitosan to PEO is 30/70, and the concentration of HAc is 2%wt.2. The applied voltage, flow rate, temperature and the distance from tip to collector have little influence on spinnability of chitosan/PEO aqueous HAc solutions, but can affect the morphology of the chitosan/PEO fibers. The favor processing parameters are as below:the voltage is 20kV, the flow rate is 0.8ml/h, the temperature is 35℃and the distance from tip to collector is 21cm.3. The contact angles of the chitosan/PEO nanofiber membranes were reduced after treated by alkaline air (NH3) in low-temperature plasma. And the reinforcing of FTIR at -NH2 peak(1590-1650cm-1) showed that the -NH2 group were ingrafted on the chitosan/PEO nanofiber membranes.4. From FTIR, XRD, CA and DSC analyses, chitosan and PEO have good miscibility and compatibility in HAc. The hydrogen bond between chitosan and PEO decreased the interruptive action of amido during the process of electrospinning. The addition of PEO can improve the spinnability of chitosan,and the hydrophilicity of electrospinninnig membrances.