Study on Sub-Tg Storage Effect of Polyethlene Naphthalate Using Irradiation Thermoluminescence Method

The Sub-Tg storage effect （physical aging） of poly 2,6 （ethylene naphthalate） （PEN） has been inverstigated by irradiation thermoluminescence （RTL） method. Two overlapping RTL peaks were resoluted by microcomputer. It has been identified that the second peak appeared at 114℃ attributed to the glass transition, while the first peak arised at 86℃ is associated with the molecular motion of small size segments which relate to Sub-Tg storage effect. Compared with DSC ang TSC method, RTL method is a more sensitive method for studying Sub-Tg storage effect of polymers.