Temperature dependence of electroluminescence in polyethylene naphthalate

The present communication aims at considering the possibility to carry out electroluminescence (EL) measurements on insulating materials at variable temperature. For thermal regulation purpose, it is no longer possible to work under vacuum as we used to do, and thus measurements have been achieved with nitrogen gas in the ambient. The conditions for obtaining a stable signal under both AC and DC stress are described. We have considered an unsaturated polyester, poly(ethylene naphthalate), on which we have a reasonable background as regards EL features at room temperature. Changes in the EL signal are discussed based on the temperature dependencies of photoluminescence and transport properties of these materials.