Enhanced mechanical and biodegradable properties of PBAT/lignin composites via silane grafting and reactive extrusion

Biodegradable polymers , including polybutylene adipate-co-terephthalate (PBAT), can replace traditional plastics to effectively target microplastic pollution; however, their high cost limits their application. In this study, vinyltrimethoxysilane (VTMS)-grafted lignin (VL) was prepared and incorporated into PBAT to reduce its cost and improve its mechanical properties while maintaining its biodegradability. Results show that the tensile strength , Young's modulus , and biodegradation efficiency of a PBAT/VL-30% composite increased by 200%, 151%, and 96%, respectively, compared with neat PBAT. VTMS grafting onto lignin thus improves the dispersion of lignin in PBAT; a network structure of PBAT and VL is formed via reactive extrusion . This work provides a theoretical basis for the design and development of low-cost, highly biodegradable PBAT composites.