Enhancement of optical and electrical properties of PVC/PMMA blend films doped with Li4Ti5O12 nanoparticles

Nanocomposite films of polyvinyl chloride/polymethyl methacrylate (PVC/PMMA)/ lithium titanium oxide (Li4Ti5O12) were prepared through a casting method. The structural features of the prepared films were investigated using XRD, TEM, FTIR, SEM, and UV/Vis. spectroscopy techniques. XRD pattern reveals the formation of the crystalline phase of lithium titanium oxide of average crystallite size 40 nm embedded in the amorphous polymeric matrix. The average crystallite size observed from TEM images is in good agreement with the XRD results. The physical interaction between the PVC/PMMA blend and Li4Ti5O12 NPs was confirmed by FTIR through the formation of a hydrogen bond. SEM micrographs showed partial compatibility between the polymer blend and the Li4Ti5O12. UV/Vis. analysis displayed that the values of the optical energy gap are decreased with increasing the concentration of Li4Ti5O12 NPs, this means that charge transfer complexes are arising between the polymer blend and Li-ions. The DC conductivity results are explained in the light of an intrachain one-dimensional interpolaron hopping model. The obtained results recommend the choice of Li4Ti5O12 NPs as dopants to enhance the electrical properties of virgin PVC/PMMA blend. Also, nanocomposite films can be employed in different electrochemical and industrial fields such as Li-ion batteries. (C) 2019 The Authors. Published by Elsevier B.V.