The impact of modifiers of different origins on the biodegradability of polylactide-based materials was investigated. It was found that incorporating starch and epoxidized soybean oil into the polylactide matrix accelerates the biodegradation of the polymer composite. The effect of starch and epoxidized soybean oil on intermolecular interactions within the system was examined. Based on X-ray structural analysis and scanning electron microscopy, it was determined that increasing the content of epoxidized soybean oil and starch in the polylactide matrix reduces crystallinity, enhances the amorphous characteristics of the material, and promotes the formation of materials with a more complex morphology.