Papers by Keyword: PEMA

Abstract: In this work, solid polymer electrolyte compose of blended 30% poly (methyl methacrylate) grafted natural rubber (MG30)-poly (ethyl methacrylate) (PEMA) polymer blend doped with Lithium trimethasulfonate (LiCF₃SO₃) films were prepared by solution casting technique. . FTIR analysis showed that the interactions between lithium ions and oxygen atoms occur at the carbonyl functional group C=O where there is shifting in wavenumber from 1728 cm^-1 of pure blend to lower wavenumber of blended MG30-PEMA on the MMA structure in both MG30 and PEMA. DSC analysis showed miscibility of polymer blend. From Electrochemical Impedance Spectrocopy analysis, ionic conductivity increase with the increasing of salt concentration. Maximum conductivity at room temperature is 9.20 x 10^-6 Scm^-1 was obtained when 30 wt% of LiCF₃SO₃ was added into the system. Ionic conductivity temperature dependence plots found obeys the Arrhenius rule.

Abstract: Solid polymer electrolytes (SPEs) comprising of a blend of Poly (ethyl methacrylate) (PEMA) and Epoxidized natural rubber-50 (ENR50) as polymer host and lithium triflate (LiCF₃SO₃) as dopant were prepared by solution cast technique. The blend based polymer electrolytes have a fixed PEMA/ENR50 ratio of 70:30 by wt. % as at this ratio ENR-50 imparted stable mechanical properties to the otherwise fragile PEMA. The incorporation of LiCF₃SO₃ into the blend is found to increase the conductivity of PEMA/ENR50. The highest conductivity achieved was 3.64 x 10^-5 Scm^-1 at 40wt. % LiCF₃SO₃. The structure of the samples was investigated by X-ray diffraction and the results show that the highest conducting sample is the most amorphous.

Abstract: Free standing polymer electrolyte films comprising of ammonium trifluoromethane sulfonate in poly(ethyl methacrylate) were prepared and characterized. The structural and electrical properties of the polymer electrolytes were investigated by X-ray diffraction and a.c. impedance spectroscopy, respectively. The formation of polymer-salt complex has been confirmed by Fourier transform infrared spectroscopy study. Conductivity of the polymer electrolytes increased with salt content. The highest ionic conductivity in the order of 10-5 S cm-1 at room temperature was achieved for the system with 35 wt% of ammonium salt. The temperature dependence of conductivity obeyed the Vogel-Tammam-Fulcher relation. The activation energy has been calculated from the VTF formalism. The ionic transference number of the mobile ions estimated by Wagner’s polarization method was close to unity for the highest conducting sample implying that the conductivity was contributed by ions which was expected to be protons.

Abstract: The present study focuses on preparation of ENR-50/PEMA-NH4CF3SO3 proton conducting polymer electrolytes by solution casting technique. Conductivity increases with NH4CF3SO3 concentration up to 40 wt.% but decreases with further increase in salt content. The temperature dependent conductivity study shows that the conductivity-temperature behaviour of ENR-50/PEMA-NH4CF3SO3 electrolytes follows the VTF rule. DSC studies show that the Tg increases with increase in salt content. This means that the increase in conductivity of ENR-50/PEMA-NH4CF3SO3 is incorrelated to the increase of the segmental motion of the host polymer chains but may be attributed to the increase in the concentration and migration rate of charge carriers.