Semi-interpenetrating polymer network of poly(methyl methacrylate) and ether-modified polysiloxane

• Mechanically stable, “easy-to-prepare” polymer electrolytes for lithium-ion battery
• A semi-IPN consisting of PMMA and ether-modified polysiloxane were prepared.
• No interactions between ether-modified siloxane and PMMA observed.
• Porous PMMA-network filled with ether-modified siloxane
• Effective ionic conductivity calculated with regard to morphology

Solid polymer electrolyte membranes are prepared as semi-interpenetrating networks (semi-IPN) by solution casting technique composed of poly(methyl methacrylate) (PMMA) as polymeric host matrix, polysiloxane-comb-propyloxymethoxytriglycol (PSx) as ion conducting component and lithium bis(trifluoromethane)sulfonimide (LiTFSI) as conducting salt. The resulting semi-IPN (net-poly(methyl methacrylate))-sipn-(polysiloxane-comb-propyloxymethoxytriglycol), is investigated using differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy and impedance spectroscopy (IS). DSC measurements show two glass transitions (Tg-PSx, Tg-PMMA) indicating an independent coexistence of the PMMA host matrix and the PSx conducting component. FTIR spectroscopy reveals interactions between Li+ ions and the ether-functionality of PSx, whereas PMMA does not interact with the Li+. In order to distinguish PMMA and PSx contributions to the ionic transport, the effective ionic conductivity of PSx was calculated. The ionic conductivity of the semi-IPN is 3.1 × 10− 6 S cm− 1 at room temperature.