Investigation on improvement of thermal, mechanical, and barrier properties of lignin/poly(3‐hydroxybutyrate‐co‐3‐hydroxyhexanoate) using inorganic nanoparticles as fillers

Abstract In this study, four typical biocomposites from lignin blended with poly‐3‐hydroxybutyrate‐3‐hydroxyhexanoate (PHBH) using inorganic nanoparticles (INPs) (SiO₂, MMT, CaCO₃, and BN) as fillers were evaluated, which enhanced the thermal, mechanical, and barrier properties of composites. The results revealed that the selection of suitable INPs doped into the lignin/PHBH (L/P) composites was an important approach to achieve available function. MMT/L/P nanocomposites were significantly higher than those of untreated L/P composites in thermal stability (T_max exceed 10%) and barrier properties (water vapor and oxygen resistance increased by 48% and 46%), and BN particles increased the initial thermal decomposition temperature by 8%. The elongation at break of CaCO₃/L/P and BN/L/P composites were increased by 344% and 319%, while SiO₂/L/P composites had the best tensile strength (18.8 MPa). Besides, the INPs/L/P nanocomposites in this paper exhibited excellent ultraviolet (UV) resistance and might become potential anti‐UV packaging materials for grease foods.