研究以聚乙烯（PE）为原料，聚羟基脂肪酸酯（PHA）、改性后的纳米CaCO₃和甘蔗渣纤维（BF）为复合填料，通过熔融挤压和注塑成型制备纳米CaCO₃/BF/PHA/PE复合材料。通过力学性能测试、傅里叶变换红外光谱（FTIR）分析、热重（TG）分析、扫描电子显微镜（SEM）等表征方法，考察PHA含量、改性纳米CaCO₃及BF的最佳配比及其含量对复合材料内部结构和性能的影响。结果表明：5%PHA、5%BF以及5%纳米CaCO₃时，复合材料的力学性能最佳，达到12.9 MPa；在此配比下，纳米CaCO₃/BF/PHA/PE复合材料的最大热分解温度达到463 ℃，高于改性前复合材料热分解温度（453 ℃）。研究为可降解高分子材料的绿色发展提供了思路。

In this study, polyethylene (PE) was used as the raw material, and polyhydroxyalkanoate (PHA), modified nano-CaCO₃ and bagasse fiber(BF) were used as the composite fillers, and the nano-CaCO₃/BF/PHA/PE composites were prepared by melt extrusion and injection molding. The effects of the optimal ratios of PHA, modified nano-CaCO₃ and BF and their contents on the internal structure and properties of the composites were investigated by mechanical property tests, Fourier transform infrared spectroscopy (FTIR) analysis, thermogravimetric (TG) analysis, scanning electron microscopy (SEM) and other characterization methods. The results show that with 5% PHA, 5% BF, and 5% nano-CaCO₃, the mechanical properties of the composites were optimal at 12.9 MPa, and the maximum thermal decomposition temperature of the nano-CaCO₃/BF/PHA/PE composites reached 437 ℃ at this ratio, which was higher than the thermal decomposition temperature (453 ℃) of the composites before modification. The study provides ideas for the green development of degradable polymer materials.