Rapid room-temperature polymerization of bio-based multiaziridine-containing compounds

Successful Michael addition under mild reaction conditions resulted in the grafting of 2-methyl aziridine onto acrylated epoxidized soybean oil, and the aziridine content was titrated as 0.00413 mol g(-1). Multiaziridine-containing acrylated epoxidized soybean oil (AESO-AZ) was then subjected to rapid room-temperature polymerization with succinic acid, citric acid, and an isosorbide-based diacid, respectively. The polyacids were added to AESO-AZ at stoichiometric ratios. The resulting polymeric materials were cast into films in order to investigate their thermo-mechanical properties. Differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermogravimetric analysis (TGA), and tensile stress-strain tests were performed. The glass transition temperatures (T-g) of the samples suggested that increased functionality of the carboxylic acid groups in the polyacids may have effectively increased T-g, while the rigid rings in isosorbide did not have significant impact on T-g. This work illustrates the feasibility of synthesizing bio-based multiaziridine-containing compounds that can be used as the monomer for rapid polymerization with bio-based polyacids at ambient temperature.