Effect of large sized reed fillers on properties and degradability of PBAT composites

Abstract In this paper, large‐size reeds were introduced into PBAT to prepare high‐performance biodegradable composites by high‐speed blending without compatibilizer. Subsequently, the effects of large‐size reeds on the composite properties and biodegradation behavior were further investigated. The length of the reed in composites reaches to ~1.88 mm. It was found that all composites showed larger modulus and flexural strength than PBAT, and a significant increase in heat deflection temperature. By mixing 60% reed and PBAT, the bending strength, bending modulus, and heat deflection temperature reached 23.9 ± 0.4 MPa, 1237 ± 143 MPa, and 71.8°C, respectively. Biodegradation tests showed that the primary bond‐breaking site of PBAT was the C=O group. Compared with pure PBAT, the composites exhibited more significant mass loss, decreased thermal stability, increased melting point, and decreased crystallinity during degradation. A surface erosion degradation model for the composites was proposed. The research provides a scientific basis for applying high‐performance biodegradable composites to biodegradable blister and injection molded products.