Effect of structure on the thermal stability of curable polyester urethane urea acrylates

Abstract

A series of poly (ester-urethane-urea)s containing pendant acrylate and methacrylate functionality has been prepared in the presence of the inhibitors of double bond polymerization and without. Introducing diamine and methacrylic structural units extends the hard urethane segments. The effect of structural segments on the thermal stability of curable poly(ester urethane urea) acrylates was studied. A series of compounds, where one segment of the molecular structure was varied, was tested for thermal stability. Increasing the length of the soft segment increases the thermal stability within a given series of compounds. The thermal oxidative stability of the polyurethane acrylate curing system was measured by TGA under air atmosphere. The decomposition of polyurethane acrylates and polyurethane methacrylates has been compared. Polyol-based urethane urea acrylates were found to be more stable than their amine counterparts. It was verified that the presence of urea groups and longer soft segments promoted an increase in the thermal stability. The oligomer structure and presence or not of the inhibitor of double bond polymerization, all afect the thermal stability of the cured coatings.