Most of the current lubricants originate from petroleum stock, which may make them difficult to dispose of and be environmentally unfriendly. Triglyceride oils are good platforms for new products that can substitute for conventional mineral oil-based lubricating oils and synthetic esters. As part of the effort to develop new uses of triglyceride oils, a modified triglyceride oil was synthesized through the reactions with 4-phenyl-1,2-4-triazoline-3,5-dione (PTAD). The process required no solvent or catalyst and entailed only the mixing of triglyceride and PTAD. 1H NMR was used for structure determination and to monitor the reactions. Several reaction products were produced, and their relative yields depended on the stoichiometry and temperature of the reaction. The reaction product mixture exhibited a self-curing behavior as a function of time. Thus, the viscosity of a mixture containing PTAD and triglyceride in a 3:10 weight ratio increased 40-fold in about 2 h at room temperature, suggesting its possible use as an additive in lubricants, caulking, cement and thickener applications.