I. Vonlampe et al., THERMOGRAVIMETRIC AND ESR STUDIES OF POLYMER METAL PRECURSORS FOR HIGH-TEMPERATURE SUPERCONDUCTORS/, Die Angewandte makromolekulare Chemie, 251, 1997, pp. 157-170
Bi-Sr-Ca-Cu complexes of poly(methacrylic acid) (PMAA) and cresol novo
lac, which are precursors for high-temperature superconductors (HTSC)
and Cu complexes of those polymers were investigated by ESR spectrosco
py and thermogravimetry. In the PMAA samples three different kinds of
Cu2+ species were detected: i) Cu2+ pairs, ii) isolated Cu2+ ions and
iii) Cu2+ clusters. While Cu2+ pairs are the main species at low Cu co
ncentrations, clusters become dominant at high Cu contents. In the nov
olac samples Cu2+ was only detected in isolated sites and clusters. Th
e introduction of Cu ions lowered the thermal stability of the polymer
s and led to a stepwise decomposition. In the PMAA samples the first d
ecomposition step at approximate to 220 degrees C is caused by the Cu2
+ pair complexes.