Acrylic acid-modified starch has been achieved by grafting the starch with an acrylic acid homopolymer by using the biodegradable nonionic surfactant Lutensol-XL-100 (decaoxyethyele n-decyl ether) and ammonium persulfate as a free radical originator. After obtaining the optimized starch-based plastic thin film, a nanocomposite (NC) was created by incorporating nickel-doped zinc oxide nanoparticles (ZnO@Ni NPs), which served as the control for the degradation rate of the composite plastic. The NC was characterized using FTIR, TGA, DSC, and SEM. The ZnO@Ni NPs induced an antibacterial property in the composite film with improved thermal stability and effective to control bacterial growth. The starch-grafted polyacrylic acid exhibited 23.21% biodegradability in 60 days while its NC showed 16.19% at the same time by a soil burial test. It was observed that the composite film exhibited a significant efficacy against the bacteria.