The Preparation And Properties Of Hyperbranched Poly(Urea-urethane)/Graphene Oxide Electrospun Nanofibrous Membrane

Hyperbranched polyurethane (HPU) has been paid much attention due to its low viscosity, solubility and large amounts of end-groups, etc. Hyperbranched polyurethane has potential applications in coating, drug carrier and photochemical molecular devices and poly electrolyte, etc. The conductivity and hydrophobicity of hyperbranched polyurethane are of importance in its applications. It is necessary to improve the relevant properties of hyperbranched polyurethane. Graphene oxide (GO), the oxygenated counterpart of graphene, has the similar structure of graphene. Most of no-oxided area in graphene oxide can form a conductive bridge. Graphene oxide has various functional groups (e.g. carbonyl, hydroxyl groups) covalently bonded on their basal planes and edges of carbon atoms. So graphene oxide is hydrophilic and can be readily dispersed in water and organic solvents to form stable colloidal suspensions. In addition, graphene oxide is rather hydrophobic. Therefore, it is possible to improve the conductivity and hydrophobicity of hyperbranched polyurethane materials via incorporating grapheme oxide in them.In this study, the hyperbranched poly(urea-urethane)/grapheme oxide electrospun nanofibrous membrane was prepared and its properties were investigated.1. HPU is synthesized with MDI and DEOA as raw materials and characterized by FTIR,1H NMR、13C NMR and GPC. The electrospinning technology was used to prepare nanofibrous membrane.2. GO is synthesized from natural graphite powders by the modified Hummers method. The hyperbranched poly(urea-urethane)/graphene oxide electrospun nanofibrous membrane was prepared via the mixing method and subsequent electrospinning. The morphology, conductivity, thermal stability and hydrophobicity were investigated. The results suggested that the comprehensive performance of HPU/GO composite with2%wt GO was desirable.3. GO is synthesized from natural graphite powders by the modified Hummers method. The hyperbranched poly(urea-urethane)/graphene oxide electrospun nanofibrous membrane was prepared via the copolymerization and subsequent electrospinning. The morphology, conductivity, thermal stability and hydrophobicity were investigated. The results suggested that the comprehensive performance of HPU/GO composite based on copolymerization is better than that based on mixing method.