Preparation and properties of hydroxyapatite modified B72 composites for adhesion of partially-fossilized bone cultural relics

This study aims to improve the restoration of fragile archaeological bone artifacts by overcoming the brittleness and limited reversibility of traditional adhesives. An organic–inorganic composite adhesive was developed by incorporating hydroxyapatite (HAP) and a silane coupling agent (KH550) into Paraloid B72. The structure, morphology, and thermal stability were characterized by FTIR, SEM, and TGA. The effects of HAP content and coupling agent ratio on mechanical properties, aging resistance, and reprocessability were evaluated.The optimal formulation, containing 20 wt% HAP and 5 wt% KH550, achieved an adhesive strength of 0.27 MPa, representing a 14.4% improvement over pure B72, while maintaining good workability and aging resistance. The composite exhibited stable thermal behavior and satisfactory reversibility. The HAP/B72 adhesive provides a balanced combination of bonding strength, thermal stability, and reprocessability, demonstrating strong potential for bone artifact conservation.