Thermal degradation of poly(methacrylic acid) and Y-Ba-Cu polymethacrylate precursors for the preparation of high temperature superconductors

摘要

The polymer precursor technique is a simple and inexpensive method for the preparation of high temperature superconductor (HTSC) powders and films. This paper presents the results of thermoanalytical (TA) and FTIR investigations of poly(methacrylic acid) (PMAA) and Y-Ba-Cu poly(methacrylic acid) precursors. There are significant differences in the thermal degradation in air and in inert atmosphere. This knowledge is used to explain the specific two-step preparation procedure of the HTSC thin film. Superconducting transition temperatures of resulting thin film samples are reported. Furthermore, the preparation of Ca and K doped YBCO from analogous PMAA precursors was investigated. The influence of these dopants on the superconducting transi- tion temperature is demonstrated.