Electrospun poly(vinylidene fluoride)/poly(methyl methacrylate) grafted TiO2 composite nanofibrous membrane as polymer electrolyte for lithium-ion batteries

An organic/inorganic hybrid nanocomposite , poly(methyl methacrylate) grafted titanium dioxide (PMMA- g -TiO 2 ), is synthesized by atom transfer radical polymerization (ATRP). The hybrid nanocomposites are incorporated into poly(vinylidene fluoride) (PVdF) membranes during the electrospinning process to fabricate a composite nanofibrous membrane. Then the resultant fibrous polymer electrolyte is obtained by immersing the composite membrane into liquid electrolyte . FTIR , TEM , TGA , GPC , SEM, XRD , and DSC are used to characterize the structure, morphology and thermal properties of PMMA- g -TiO 2 hybrid nanocomposite and the composite nanofibrous membrane. The composite nanofibrous membrane is proven to be a good absorbent for the liquid electrolyte, and it exhibits a high electrolyte uptake and a high electrolyte retention ratio. The incorporation of PMMA- g -TiO 2 into the nanofibrous membrane inhibits the crystallization of PVdF during the solidification process and improves the ionic conductivity of the fibrous polymer electrolyte from 2.51 × 10 −3 to 2.95 × 10 −3  S cm −1 at 20 °C. The electrochemical stability window of the polymer electrolyte is also enhanced due to the presence of PMMA- g -TiO 2 .