Advanced Biodegradable Materials: The Development of PBS Hybrid Composites Reinforced With Natural Fibers, Lignin, and Sepiolite for Sustainable Applications

Abstract

The increasing demand for sustainable materials has led to the development of biodegradable polymer composites. This study examines polybutylene succinate (PBS) hybrid eco-friendly composites reinforced with canabrava fiber (CANA), lignin (LIG), and sepiolite (SEP), with epoxidized soybean oil (ESB) as a compatibilizer and plasticizer, for potential applications in agricultural packaging, especially trays for plant seedling production and/or plant pots, whose recycling process is difficult due to the logistical gap, where controlled degradation and eco-friendliness can be beneficial. Mechanical analysis reveals a significant increase in stiffness, with Young's modulus rising by up to 309%, while impact resistance decreases due to increased brittleness. The incorporation of SEP enhances flexural modulus and strength, while LIG contributes to improved melt flow properties. ESB improves the rheological behavior, although it fails to increase elongation and ductility. Thermal analysis indicates that SEP increases the crystallization temperature from 77.1°C (PBS) to 83.6°C (2PBS-08), promoting improved crystallinity. Fourier transform infrared (FTIR) spectroscopy confirms strong interactions between PBS and SEP, suggesting effective filler dispersion. Biodegradation tests show a 9.0% mass loss for the composite (2PBS-09) after 90days, compared to 4.8% for neat PBS, highlighting enhanced degradation. Scanning electron microscopy (SEM) confirms good fiber–matrix adhesion and uniform filler dispersion. These results demonstrate the potential of PBS hybrid composites as a sustainable alternative to conventional plastics, offering a balance between cost, mechanical performance, biodegradability, and structural integrity.