Studies of porous solid polymeric electrolytes based on poly (vinylidene fluoride) and poly (methyl methacrylate) grafted natural rubber for applications in electrochemical devices

摘要

The potential of new porous solid polymer electrolyte (SPE) for poly (vinylidene fluoride)-poly (methyl methacrylate) grafted natural rubber (PVDF-MG49) doped with LiCF3SO3 based on application in electrochemical device system has been investigated. The characteristics of the samples are analyzed and studied using electron impedance spectroscopy (EIS), X-ray diffraction (XRD), scanning electron microscopy (SEM), attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and linear sweep voltammetry (LSV). Ionic conductivity of 3.25 x 10(-4) S cm(-1) is achieved at room temperature, and the studies suggested that ion transport proceeds in these materials via a hopping mechanism similar to what is found in an ionic crystal. It is found that dielectric constant and dielectric loss increase with salt contents. A similar situation is also observed in electrical modulus. Analysis of XRD shows a decrease in crystallinity peaks of methyl methacrylate (MMA) in MG49 with the amount of added salt. The observations from SEM micrographs show porosity structure of polymer electrolyte. Based on the FTIR results, we are able to conjecture that interactions between the lithium ion and with the oxygen atoms from the MMA likely occur. Electrochemical studies show that polymer electrolyte has high electrochemical stability windows and is favorable for application in electrochemical devices.