Insights into biobased epoxidized fatty acid isobutyl esters from biodiesel: Preparation and application as plasticizer

Biodiesel was used to prepare epoxidized fatty acid isobutyl esters (Ep-FABEs) as a biobased plasticizer in this work. Transesterification of biodiesel with isobutanol catalyzed by tetrabutyl titanate was carried out in a gas-liquid tower reactor. The conversion achieved nearly 100% within 5 h under the reaction temperature, the mass ratio of catalyst to fatty acid methyl esters (FAMEs), and isobutanol to FAMEs total molar ratio of 180 °C, 0.4 %(mass), and 5.4:1, respectively. In addition, kinetic model of the transesterification reaction was developed at 150–190 °C. The calculated activation energy was 48.93 kJ·mol −1 . Then, the epoxidation of obtained fatty acid isobutyl esters (FABEs) was conducted in the presence of formic acid and hydrogen peroxide. The Ep-FABEs was further analyzed for its plasticizing effectiveness to replace dioctyl phthalate (DOP) and compared with conventional epoxy plasticizer epoxidized fatty acid methyl esters (Ep-FAMEs). The results indicated that the thermal stability and mechanical properties of PVC films with Ep-FABEs plasticizer were significantly improved compared with those plasticized with DOP. In addition, the extraction resistance and migration stability of Ep-FABEs were better than those of Ep-FAMEs. Overall, the prepared Ep-FABEs via structural modification of biodiesel proved to be a promising biobased plasticizer.