偶联剂处理对碳纤维/竹展平板复合材料界面结合强度的影响

Effect of coupling agent treatment on interfacial bonding strength of carbon fiber/flattened bamboo composite

碳纤维/竹展平板是提高竹材在工程产品中应用的一种新型复合材料。胶合界面是复合材料传递力的桥梁,胶合界面的胶合性能是影响复合材料整体力学性能的关键。研究了羟甲基化间苯二酚(Hydroxymethylated resorcinol,HMR)偶联剂处理竹展平板表面对碳纤维/竹展平板复合材料的胶合性能的影响,按照不同的组坯方式和竹展平板表面处理方式将测试的试件分为4组。从碳纤维/竹展平板复合材料胶合界面的端面密度分布梯度、应变分布和应力传递及微观形貌3个角度进行测试分析。结果表明:HMR偶联剂处理后,碳纤维/竹展平板复合材料的胶合强度相较于未处理组提高了42.7%;碳纤维/竹展平板复合材料胶合界面密度明显增大,胶层厚度变宽,胶层应变分布和应力传递更加均匀,HMR偶联剂起到了良好的桥接作用;HMR偶联剂与碳纤维协同作用,使胶合界面的应力传递更连续,提高了碳纤维/竹展平板复合材料的胶合性能。

Carbon fiber/flattened bamboo composite is a new kind of composite material to improve the application of bamboo in engineering products.The bonding interface is the bridge of the transfer force of composite materials,and the bonding property of the bonding interface is the key to the overall mechanical properties of composite materials.The effects of hydroxymethylated resorcinol(HMR)coupling agent on the bonding properties of carbon fiber/flattened bamboo composite were studied.The specimens were divided into four groups according to different forms and treatment methods of flattened bamboo surface.The vertical density distribution,strain distribution,stress transfer and microstructure of the bonding interface of carbon fiber/flattened bamboo composite were measured and analyzed.Results show that the bonding strength of carbon fiber/flattened bamboo composite after treatment with HMR coupling agent is increased by 42.7%compared with that of the untreated group.The bonding interface density of carbon fiber/flattened bamboo composite increases,the thickness of the bondline is wider and the strain distribution and stress transfer more evenly.HMR coupling agent plays a good role in bridging and acts synergistically with carbon fiber to make the stress transfer at the bonding interface more continuous and improves the bonding properties of carbon fiber/flattened bamboo composite.