A monomer was synthesized using the mixture of fatty acids obtained through the hydrolysis of triglycerides extracted from spent hens. The reaction conditions of temperature and time were studied to obtain a high molecular weight biopolymer using bulk polymerization. The bionanocomposites were then prepared with different ratios of nanoclay (0, 3, 5, and 10 %) addition using in situ polymerization. The bionanocomposite films were prepared using compression molding and the effect of nanoparticle addition, in terms of their dispersion, was investigated by different characterization techniques. Results showed enhanced thermal stability for nanoreinforced biocomposites. The flammability test showed substantial improvements in the flame retardancy of bionanocomposites compared to the neat homopolymer. These findings suggest that high-performance bionanomaterials can be prepared from spent hen lipids through in situ addition of nanoclay during polymerization.