冻-融循环老化对竹纤维/聚丙烯复合材料性能的影响  

Effect of freeze-thaw cycle aging on properties of bamboo fiber/polypropylene composites

作　　者：李振宇 李新功[1] LI Zhenyu;LI Xingong(School of Materials Science and Engineering,Central South University of Forestry and Technology,Changsha 410004,China)

机构地区：[1]中南林业科技大学材料科学与工程学院,长沙410004

出　　处：《复合材料学报》2024年第11期6148-6155,共8页Acta Materiae Compositae Sinica

基　　金：湖南省科技创新计划项目(2021RC4062)。

摘　　要：竹纤维/聚丙烯(BF/PP)复合材料常应用于户外市政工程领域。在高纬度地区时冷热湿冻的交变作用会使材料性能严重劣化。为探究BF/PP复合材料在高纬度地区的耐老化性能,采用相容剂和偶联剂协同改性的方法制备了BF/PP复合材料,研究了该材料在冻-融循环老化处理后的物理力学性能及表观性能的变化规律。采用5400 s短期蠕变试验方法研究了材料的蠕变行为,并采用扫描电子显微镜和傅里叶红外光谱分析了材料的微观形貌与化学组成。结果显示:720 h冻-融循环老化后,BF/PP复合材料的抗拉强度、抗弯强度、弯曲弹性模量、无缺口冲击强度的保留率分别为76.90%、86.89%、82.81%、71.83%;材料产生了较深的交叉裂纹、孔洞和断层,表面疏水性下降,并出现了明显的色泽改变。进一步采用Burgers模型对BF/PP复合材料的5400 s短期蠕变行为进行了拟合,探明了冻-融循环老化对BF/PP复合材料抗蠕变性能的影响机制。Bamboo fiber/polypropylene(BF/PP)composites are often used in the field of outdoor municipal engineering.In high latitude areas,the alternating effect of cold,heat,humidity,and freezing will seriously deteriorate the properties of the materials.In explore the aging resistance of BF/PP composites in high latitudes,BF/PP composites were prepared by synergistic modification of compatibilizer and coupling agent.After freeze-thaw cycle aging treatment,the physical and mechanical properties and apparent properties of the materials were studied.The creep behavior of the material was studied by 5400 s short-term creep test method,and the micro morphology and chemical compositions of the materials were analyzed by scanning electron microscopy and Fourier transform infrared spectroscopy.The results show that after 720 h freeze-thaw cycle aging,the retention rates of tensile strength,flexural strength,flexural elastic modulus,and notched impact strength of BF/PP composites are 76.90%,86.89%,82.81%and 71.83%,respectively.Deep cross cracks,holes,and faults formed in the BF/PP composite,and the surface hydrophobicity of the BF/PP composite decreased,and obvious color changes occurred.The 5400 s short-term creep behavior of BF/PP composites was further fitted by Burgers model,and the influence mechanism of freeze-thaw cycle aging on the creep resistance of BF/PP composites was explored.

关 键 词：生物质复合材料 竹纤维 老化 冻融循环 聚丙烯 力学性能 

分 类 号：TB332[一般工业技术—材料科学与工程]