纳米SiO2仿生矿化增强竹纤维/聚乳酸复合材料界面性能  

Interface Properties of Bamboo Fiber Reinforced Polylactic Acid Composite Modified by Nano-SiO2 Biomimetic Mineralization

作　　者：张凯强 张双保[2,3] Zhang Kaiqiang;Zhang Shuangbao(Guodian United Power Technology Co.,Ltd.,Beijing 100089;Key Laboratory of Wood Material Science and Application of Ministry of Education,Beijing Forestry University,Beijing 100083;Beijing Key Laboratory of Wood Science and Engineering,Beijing Forestry University,Beijing 100083)

机构地区：[1]国电联合动力技术有限公司,北京100089 [2]北京林业大学木质材料科学与应用教育部重点实验室,北京100083 [3]北京林业大学木材科学与工程北京市重点实验室,北京100083

出　　处：《林业科学》2025年第3期189-198,共10页Scientia Silvae Sinicae

基　　金：国家自然科学基金项目(32171707);北京市自然科学基金项目(6202024)。

摘　　要：【目的】探究纳米SiO_(2)与多巴胺/聚乙烯亚胺仿生矿化改性界面增强机理,为改善竹塑复合材料界面相容性的改性新方法提供理论依据。【方法】以聚乳酸树脂为基体、竹纤维为增强材料,利用多巴胺/聚乙烯亚胺杂化聚合在竹纤维表面构筑功能涂层,经“溶胶凝胶”制备纳米SiO_(2),通过静电作用诱导纳米SiO_(2)在竹纤维表面富集和生长,提高界面结合强度。采用傅里叶红外光谱、X射线光电子能谱、X射线衍射等分析改性前后纤维表面元素和纤维结晶结构变化,通过力学性能测试、扫描电子显微镜测试、热稳定性测试、差示扫描量热测试、动态热机械性能测试探究纳米SiO_(2)仿生矿化改性提升竹塑复合材料界面相容性的机理。【结果】经纳米SiO_(2)仿生矿化改性后的竹纤维表面Si元素含量明显增加,竹纤维结晶结构未发生改变。力学性能测试结果表明,纳米SiO_(2)仿生矿化改性后,复合材料的弯曲强度、拉伸强度和抗冲击强度分别提高18.99%、15.91%和34.34%。扫描电子显微镜测试结果表明,改性后复合材料界面处纤维被拔出现象减少,纤维表面更加粗糙,纤维与基体之间的界面结合更加紧密。热稳定性测试结果表明,纳米SiO_(2)引入使得纤维热降解温度向高温区移动,复合材料的初始降解温度和最大热降解速率温度分别提高22.81和11.54℃,复合材料的热稳定性增加。差示扫描量热测试结果表明,改性纤维与基体之间的相互作用增强,聚乳酸分子运动阻力增大、复合材料的结晶度降低、复合材料的熔融温度升高。动态热机械性能测试结果表明,改性后复合材料储能模量提高、损耗模量降低,说明复合材料内部缺陷减少,复合材料界面性能得到提高。【结论】纳米SiO_(2)仿生矿化改性在竹纤维表面形成SiO_(2)的有机-无机杂化改性网络,增强纤维与基体之间的机械锚合与化学键合【Objective】This study aims to explore the enhancement mechanism of the interface modified by biomimetic mineralization of nano-SiO_(2) and dopamine/polyethylenimine,so as to provide a basis for the modification of bamboo fiber by biomimetic mineralization of nano-SiO_(2) and improve the interface compatibility of bamboo plastic composites.【Method】Using polylactic acid resin as matrix and bamboo fiber as reinforcement material,functional coating was constructed on the surface of bamboo fiber by dopamine-polyethylenimine hybrid polymerization,and nano SiO_(2) was prepared by“sol-gel”.Through electrostatic interaction,nano SiO_(2) was induced to accumulate and grow on the surface of bamboo fiber,and then to improve the interface properties.Fourier infrared spectroscopy,X-ray photoelectron spectroscopy and X-ray diffraction were used to analyze the changes of fiber surface elements and fiber crystal structure after modification.The mechanism of bionic mineralization modification of nano-SiO_(2) to improve the interface compatibility of bamboo plastic composite was comprehensively discussed through mechanical property testing and analysis,thermogravimetric analysis,scanning electron microscopy and dynamic thermomechanical property analysis.【Result】The nano-SiO_(2) was attached to the fiber surface,and the content of Si element on the surface of bamboo fiber was significantly increased,and the modification did not cause the change of fiber crystal structure.The test of mechanical properties showed that the bending strength,tensile strength and impact strength of the composite modified by nano-SiO_(2) bionic mineralization are increased by 18.99%,15.91%and 34.34%,respectively.SEM analysis showed that the fiber pulling out at the interface of the modified composite was reduced,the fiber surface was coarser,and the interface bond between the fiber and the matrix was closer.The thermogravimetric analysis showed that the introduction of nano-SiO_(2) improved the thermal stability of the composite,and the the

关 键 词：竹纤维 纳米SIO2 界面性能 增强机理 复合材料 

分 类 号：S785[农业科学—林学] TB330.1[一般工业技术—材料科学与工程]