Thermal Study of Aluminum Trifluoromethyl Sulfonate as Effective Catalyst for the Polymerization of Epoxidized Linseed Oil

Abstract

It was studied the Aluminum Trifluoromethyl Sulfonate ((Al(OTf)3) as a very effective catalyst to polymerize Epoxidized Linseed Oil (ELO) in bulk, in a very wide range of temperatures, from room temperature (25°C) to the peak temperature of the exothermal curve of polymerization. Those temperatures and times of polymerization were depending on the amount of catalyst, which was evaluated in a very wide range of loads, from 0.5 x10-3 to 70 x10-3 molar percent. As an instance, a 55 x10-3 molar percent of catalyst showed at exothermic curve from 82 to 187°C with the peak temperature at 120.3°C. This preparation allows to ELO polymerize at 25°C in 24 hrs, at 60°C in 1hr and at 80°C in 20 min and only takes 7 min to polymerize at peak temperature. The study of the opening of the epoxy ring and polymerization of ELO was made by DSC and FTIR-HART analysis. Also was evidenced by 1H-NMR that no side reactions are promoted by this catalyst at least in the first minutes of reaction.