Developing High‐Performance Biodegradable Poly(Butylene Succinate) Composites Through Synergistic Effects of Fiber Surface Mineralization and Soybean Protein Bonding Onto Sisal Woven Fabrics

ABSTRACT The environmental challenges of traditional petrochemical composites have driven increasing research into sustainable alternatives. Poly(butylene succinate) (PBS) composites reinforced by sisal fabric present a promising route, yet their performance is limited by poor fiber‐matrix interfacial bonding and inadequate resin infiltration into the narrow inter‐fiber spaces. To address these issues, we adopted a dual modification strategy combining in situ CaCO 3 mineralization with soybean protein (SP) bonding. A non‐rinsing Ca(OH) 2 pretreatment captures atmospheric CO 2 to precipitate CaCO 3 particles on the fiber surface, forming a mineralized layer that enables robust mechanical interlocking with PBS. An SP/glycerol triglycidyl ether (GTE) emulsion was then applied to bond individual fibers into an integrated bundle. The resultant CaSPSF‐10%/PBS composite achieves a tensile strength of 47 MPa (26% increase over untreated SF/PBS) and a flexural strength of 53 MPa (37% increase), while water absorption and thickness swelling are drastically reduced from 2.96% and 2.20% to 1.59% and 1.42%, respectively. Moreover, the composite shows 52% mass loss after 100 days of soil burial, significantly outperforming neat PBS in biodegradability. This work provides a simple pathway to high‐performance biodegradable composites through the synergy of mineral anchoring and protein crosslinking, overcoming the limitations of fabric‐reinforced biocomposites and opening new avenues for sustainable materials.