Spectroscopic,Mechanical and Dynamic-Mechanical Studies on the Photo-Aging of a Tetrafunctional Epoxy Resin

The photo-oxidative degradation of a densely cross-linked epoxide/diamine network based on tetraglycidyl-4,4′ diaminodiphenylmethane (TGDDM) and 4,4′ diaminodiphenyl sulphone (DDS) has been investigated by FTIR spectroscopy, dynamic-mechanical analysis (DMA) and compressive mechanical tests. The FTIR measurements allowed us to monitor the degradation process of the different groups present in the TGDDM/DDS network and to obtain reliable kinetic data. On this basis the most likely photo-degradation mechanisms were proposed. Dynamic-mechanical measurements and mechanical compressive tests were used to gain an insight in the effect of the photo-oxidative degradation on the relaxation processes of the epoxy network and on the mechanical performances.