目的 为改善纤维增强聚乳酸(PLA)复合材料增强相与基体相之间差的界面结合。方法 以秸秆粉(SP)为填料，纳米二氧化钛(TiO2)作为界面改性剂，构建SP/PLA复合材料相容界面，通过力学性能测试、吸水率测试、扫描电子显微镜(SEM)、X射线衍射(XRD)和热重分析法(TGA)等表征手段，探究不同含量纳米二氧化钛对SP/PLA复合材料力学性能和界面相容性的影响。结果 研究发现，纳米二氧化钛的质量分数为2.0%时，复合材料的拉伸强度和弯曲强度分别达到42.78 MPa和91.25 MPa，其耐水性能、结晶度、耐热性能也达到最好。结论 纳米二氧化钛可有效提高秸秆/聚乳酸复合材料的性能。

The work aims to improve the poor interfacial bonding between the reinforcement phase and the matrix phase of fiber reinforced polylactic acid (PLA) composites. The compatible interface of SP/PLA composite was constructed with straw powder (SP) as filler and nano titanium dioxide (TiO2) as interface modifier. The effects of different content of nano titanium dioxide on the mechanical properties and interface compatibility of SP/PLA composite were investigated by means of mechanical property test, water absorption test, scanning electron microscope (SEM), X-ray diffraction (XRD) and thermogravimetric analysis (TGA). The study showed that the tensile strength and bending strength of the composite reached 42.78 MPa and 91.25 MPa respectively, and its water resistance, crystallinity and heat resistance were also the best when the content of nano titanium dioxide was 2.0%. Nanometer titanium dioxide can effectively improve the properties of straw/PLA composites.