Fluorescent thiol-epoxy thermosets obtained from diglycidylether of bisphenol A and carbazole based diepoxy monomer

Abstract

A new epoxy resin containing carbazole moieties was synthesized and added in several proportions to diglycidylether of bisphenol A (DGEBA) and trimethylolpropane tris(3-mercaptopropionate) (TTMP) formulations that were thermally cured by thiol-epoxy click reaction. The curing was catalyzed by a latent amine precursor, which after triggering at high temperature liberates the amine that enables the formation of thiolate groups. The curing process of the different formulations was monitored by calorimetric analysis, which allowed to observe that the increase of the proportion of the synthesized epoxy resin with carbazole groups in the formulation decreased the curing rate. However, all these formulations cured quickly after triggering, which make them adequate for the formation of layers in multilayer devices.

Thermal characteristics of the obtained thermosets were determined by calorimetric, thermomechanical and thermogravimetric analysis. The obtained thermosets have good thermal stability. Their glass transition temperature increased when the proportion of the carbazole containing resin was increased in the formulation. The photophysical properties of the thermoset films were studied and it was proved that they exhibit fluorescence in the range of 352 to 369 °C.