Silane-modified MOF-5 as a compatibilizer for PBAT/PLA blends: Enhancement of mechanical properties, antimicrobial properties, and water barrier properties

Abstract

To improve the weak interaction between poly (butylene adipate‐co‐terephthalate) (PBAT) and poly (lactic acid) (PLA) blends, this study added modified metal-organic frameworks (MOFs) to enhance the interfacial bonding strength between PBAT and PLA. MOF-5 nanoparticles were synthesized by room temperature synthesis and modified with KH-560. PBAT/PLA/KH-560@MOF films were prepared by solvent casting. The microscopic morphology, mechanical properties, thermal properties, hydrophobicity, water vapor transmission rate and antimicrobial properties of the composite films were investigated. The results showed that KH-560@MOF nanoparticles were uniformly dispersed in the polymer matrix of PBAT and PLA, reducing phase interface defects. Mechanical properties of PLA/PBAT improved in the presence of KH-560@MOF. The breaking elongation and tensile strength values were maximized when adding 1 wt% KH-560@MOF. Doping of KH-560@MOF improves hydrophobicity and water vapor transmission rate of films. Zn²⁺ in MOF-5 imparts antimicrobial properties to the film, showing antimicrobial activity against both Gram-positive and Gram-negative food-borne pathogens (i.e., E. coli and S.aureus). This work enriched the design of compatibilizer for the PLA/PBAT blend and provided a novel approach for expanding the application of MOFs.