“Luminescent polymers containing pyrenyl groups prepared by frontal polymerization of di(ethylene glycol) ethyl ether acrylate using Trigonox-23 as initiator”

Abstract

Thermal frontal polymerization (FP) of di(ethylene glycol) ethyl ether acrylate (DEGEEA) was carried out using as radical initiator tert-butyl peroxyneodecanoate (Trigonox-23), which has not been previously employed in FP. The influence of the initiator concentration on the formation of the propagating front, the maximum reached temperature and the front velocity was studied in detail. The results were compared to those obtained in the bulk polymerization of this monomer. Furthermore, a pyrene containing monomer was incorporated as fluorescent probe in order to obtain luminescent materials with different chromophore contents. The resulting polymers were characterized by FTIR spectroscopy in the solid state. Their thermal properties were determined by differential scanning calorimetry (DSC), which was also used to calculate the conversion degree in the FP of DGEEA at different initiator concentrations. Moreover, the optical properties of these materials were studied by absorption and fluorescence spectroscopy. The maximum amount of incorporated pyrene containing monomer in the polymer matrix was limited by its maximum solubility in DGEEA (10% wt). The presence of a excimer emission band confirmed the presence of intermolecular pyrene–pyrene interactions.