Precisely Anchored Amphiphilic Metal–Organic Frameworks at Polymer Interfaces for Robust Biodegradable Blends

Blending polylactic acid (PLA) with flexible biodegradable polymers such as polybutylene succinate (PBS) is a promising approach to enhance mechanical robustness, yet interfacial incompatibility severely limits their structural applications. Herein, we demonstrate a precise interfacial anchoring strategy using amphiphilic metal–organic frameworks (MOFs) localized specifically at the PLA/PBS interface through a Pickering emulsion technique. Optimized incorporation of MOFs (0.3 wt %) significantly enhanced mechanical properties, resulting in a ∼1.2-fold increase in tensile strength and a remarkable ∼23-fold enhancement in tensile toughness compared to unmodified blends. Comprehensive experimental characterization, supported by coarse-grained molecular dynamics (CG-MD) simulations, revealed that precise anchoring of MOFs at the soft PBS phase significantly reduced interfacial tension and enhanced interfacial chain entanglements, markedly outperforming anchoring on the rigid PLA phase. This study provides a scalable and mechanism-guided interfacial design paradigm, paving the way toward high-performance biodegradable polymer blends suitable for advanced structural and functional applications.