Research on the Structure and Properties of Green Composites From Cunninghamia lanceolata Powder‐Reinforced PBAT / PLA

ABSTRACT Polybutylene adipate/terephthalate (PBAT) and polylactic acid (PLA) are currently the most popular environmentally friendly biodegradable plastics. However, their relatively high production costs restrict broader commercialization. To reduce material costs, Cunninghamia lanceolata powder (CLP) was incorporated as a bio‐filler into PBAT/PLA composites. Due to the hydrophobicity of PLA and PBAT contrasting with the hydrophilicity of CLP, the resulting materials exhibited interfacial incompatibility, leading to reduced composite performance. To address this issue, poly(1,4‐butylene adipate) diol‐based polyurethane prepolymer (PBAPU) was added as a compatibilizer. Through a series of tests and characterizations, it was observed that as the CLP proportion increased, the compatibilizing effect of PBAPU diminished. At a CLP mass fraction of 10 wt%, the composite achieved optimal properties, with an elongation at break of 54.40%, an impact strength of 8.45 kJ/m 2 , and a melt flow index of 10.89 g/10 min. This study provides a feasible strategy for developing low‐cost, high‐performance biodegradable composites, which is of great significance for promoting the practical application of biodegradable plastics and alleviating environmental pollution caused by traditional plastics.