Investigation by TGA—FTIR of the Effect of Styrene Content and Thickness on the UV-curing of Vinylester Resins

Abstract

The influence of styrene content and thickness of the samples on the UV curing of vinyl ester/styrene resins (VERs) is investigated by DSC and the combination of TGA and FTIR (TGA—FTIR). The glass transition temperatures (T_g) of the network polymers after curing are found to be lower for the VERs with higher styrene content. The released heat during UV curing further increases the T_g, with this increase being proportional to the volume of the resins. Within the range of thickness investigated (up to 30 mm) the relative amount of emissions of styrene, VE, and CO₂ are found to be similar at the top and at the bottom of the samples. Similar results are obtained from the TGA analysis, indicating that the VERs are fully or almost fully cured all along the cross section. A good correlation is found between the analysis of the thermal properties by DSC and the results obtained by the TGA—FTIR system.

Keywords

TGA—FTIR styrene vinylester UV curing Tg heat released cross-link density.

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