This study presents a novel approach to address the current issue of plastic waste in the biosphere, which poses ecological hazards and threatens living beings. Herein, a set of biodegradable composites has been developed through the melt blending of polybutylene adipate-co-terephthalate (PBAT) and rice husk (RH), aiming to discover effective surface modification techniques for enhancing mechanical properties while maintaining biodegradability above 90%. This research studied the diverse surface treatment methodologies applied to raw RH, including alkaline, acetylation, and silane treatments. The novelty of this study lies in its focus on evaluating how these treatments distinctly influence the mechanical properties and biodegradability of RH. Additionally, it seeks to understand the underlying mechanisms driving these performance changes. To further improve the compatibility between hydrophobic PBAT and hydrophilic RH, a compatibilizer such as maleic anhydride (MAH) was added. A range of analytical techniques, including scanning electron microscopy (SEM), tensile testing, differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), contact angle measurement, and soil burial test, was employed to investigate the biodegradability of the composites. The results indicate that the PBAT/Silane RH/MAH composite exhibited exceptional mechanical properties, with a tensile strength of 22.49 MPa, a strain at break of 41.83%, and Young's modulus of 187.60 MPa. Furthermore, the composites developed exhibited 90% mass loss during a six-month soil burial test, confirming their remarkable biodegradability. The findings present an innovative and practical solution for utilizing RH waste in a wide range of applications, particularly in the production of molded products such as straws.

In this study, a novel environment-friendly PBST/PPC-based blown film was prepared using maleic anhydride (MA) as a reactive compatibilizer to enhance the compatibility between poly(butylene succinate-co-terephthalate) (PBST) and poly(propylene carbonate) (PPC). Results of rheological testing and gel permeation chromatography (GPC) indicated that MA reacted with PBST/PPC during melt-blending extrusion. Morphological analysis of the cryo-fractured surfaces of PBST/PPC blend showed significantly improved compatibility between PBST and PPC with the addition of MA. Moreover, the Young's modulus, tensile strength, breaking strain, and tear strength of PBST/PPC/MA blown films increased with an increase in MA content. In comparison to PBST/MA blown film without PPC, the barrier property of PBST/PPC/MA blown films was improved. In addition, in vitro cell experiments showed that the PBST/PPC/MA blown film was suitable for the growth of mouse fibroblast (L929) cells. In vitro ecotoxicity testing on mung bean plant showed that the extracts from the PBST/PPC/MA blown film had no negative effects on the development of mung bean plant. Furthermore, degradability testing in soil also proved that the PBST/PPC/MA blown film had good biodegradability. Thus, the PBST/PPC/MA blown film can be used in fields, such as food packaging and agricultural mulch film.