High-temperature superconducting polymer–ceramic compositions

Polymer–ceramic compositions, formed from polymeric binders (super high molecular polyethylene, polymethylmethacrylate) and superconducting ceramics (Y1Ba2Cu3O7−x), were obtained by hot-pressing at 200°C possessing 96 and 94 K transition critical temperature, respectively. Superconductivity of the composition is reduced as the ceramic’s grain surface oxygen participates in thermo-oxidation destruction reaction with the binder. Thermal treatment at α-transition temperatures and in oxygen environment restores the superconducting properties of the composition. To sustain superconductivity of the composition immediately after the hot-pressing, i.e. eliminating the stage of restoration, very small quantities, about 1% of the binder’s weight, of antioxidant organic compound has to be added in the initial mixture of polymer and ceramic. By the polymerization of methylmethacrylate of the separate pre-pressed specimens of ceramic, Y1Ba2Cu3O7−x — polymethylmethacrylate compositions were obtained. It was shown that the compositions obtained using the polymerization method maintained their superconducting properties. Anomalous impact of Y1Ba2Cu3O7−x oxide ceramic on the kinetics of the initiated polymerization of methylmethacrylate by dinitrylazoisooleic acid was observed.