Polymer blends of poly(2-cyanoethyl vinyl ether) and poly(methyl methacrylate) with improved dielectric properties for flexible electronics

There is a big demand for the development of polymer materials for flexible electronics, among them polymers with a high dielectric constant play an important role. Here the preparation and properties of a polymer blend composed of poly(2-cyanoethyl vinyl ether) (CEPVA) as an amorphous polymer with dielectric constant (epsilon') similar to 15 but glass temperature (T-g) close to room temperature, and poly(methyl methacrylate) (PMMA), a polymer with low epsilon' similar to 5 and high T-g, are reported. The film forming ability, structure and dielectric properties of the blend are reported to verify its applicability for capacitors and field effect transistors. PMMA: CEPVA ratios 10: 90 and 30: 70 represent the best composition for obtaining a monophasic system with increased dielectric constant and T-g well above the room temperature. The improved properties have been attributed to the impact of PMMA on the relaxation phenomena of CEPVA, namely to an increased mobility of cyano-groups responsible for the dielectric behavior, as it was observed by the broadband dielectric and nuclear magnetic resonance (NMR) spectroscopies.