Anomalous magnetic properties of polycondensate of fused poly nuclear aromatics(COPNA) resin

Summary form only given. The magnetic properties of the COPNA resin pre pared by photoirradiation have been studied by ESR and SQUID measurements. ESR spectra were obtained as a singlet with g=2.0035. The temperature dependence of the susceptibility (X) is shown in the figure. In the 50-150K temperature region, the value of X doesn´t follow Curie law. The X value gradually increased with time. The intensity of the ESR signal decreased in the same temperature region. Furthermore, this intensity decreased extraordinarily with increase of oxygen pressure in the sample. It was also found that this anomalous magnetic properties characteristic to the COPNA resin was related to the changes of molecular weight distribution by photoirradiation. It is considered that this behavior is due to the structural changes related to oxygen.