Ti_(3)C_(2)T_(x)-MXene上浆剂表面改性高模量碳纤维及其环氧树脂基复合材料界面性能

Ti_(3)C_(2)T_(x)-MXene sizing agent surface modified high modulus carbon fiber and its epoxy resin matrix composites interface properties

为了改善高模量碳纤维(HMCF)表面润湿性及增强其复合材料界面性能,本文采用机械共混法,将尺寸为100~500 nm的少层Ti_(3)C_(2)T_(x)-MXene水分散液与水性环氧乳液上浆剂进行复配,制备了适用于HMCF的Ti_(3)C_(2)T_(x)-MXene/环氧树脂(EP)改性环氧乳液复合上浆剂,并以连续上浆技术在HMCF表面构筑了富含Ti_(3)C_(2)T_(x)-MXene的特性涂层,以期改善HMCF/EP复合材料的界面结合性能。通过SEM、XPS和动态接触角测试对HMCF的表面形貌、表面化学状态和表面润湿性能进行了表征,并以层间剪切强度(ILSS)和断面形貌测试对HMCF/EP复合材料的界面结合状况进行了分析表征,最后以复合材料的剪切破坏模型对Ti_(3)C_(2)T_(x)-MXene/EP复合上浆剂改性的HMCF/EP复合材料的界面增强机制进行了探讨。结果表明,经Ti_(3)C_(2)T_(x)-MXene/EP复合上浆剂表面处理后,HMCF表面的O/C(原子比)提高,并赋予其一定量的纳米尺度小凸起微机械结构,改善了HMCF的表面润湿性。当环氧乳液上浆剂固含量为0.8%,Ti_(3)C_(2)T_(x)-MXene浓度为1.0 mg/mL时,HMCF/EP复合材料的ILSS值提高了23.8%,达到85.9 MPa。

In order to improve the surface wettability of high modulus carbon fibers(HMCF)and enhance the interfacial properties of their composites,a few-layer Ti_(3)C_(2)T_(x)-MXene aqueous dispersion with a size of 100-500 nm was mixed with an aqueous epoxy emulsion to prepare an Ti_(3)C_(2)T_(x)-MXene modified sizing agent for HMCF by mechanical blending method.The continuous sizing technology was used to construct a characteristic coating rich in Ti_(3)C_(2)T_(x)-MXene on the surface of HMCF in order to improve the interface bonding of HMCF/epoxy resin(EP)composites.The surface morphology,surface chemical state and surface wettability of HMCF were characterized by SEM,XPS and dynamic contact angle test,and the interface bonding of HMCF/EP composites was analyzed and characterized by interlaminar shear strength(ILSS)and cross-sectional morphology tests.Finally,the interface enhancement mechanism of Ti_(3)C_(2)T_(x)-Mxene/EP sizing agent-modified HMCF/EP composites was investigated with the shear damage models of the composites.The results show that after the surface treatment with Ti_(3)C_(2)T_(x)-MXene modified sizing agent,the O/C(atomic ratio)of the HMCF surface is increased,and a certain amount of nano-scale convex micromechanical structures are introduced to improve the surface wettability of HMCF.When the solid content of the epoxy emulsion sizing agent is 0.8%and the concentration of Ti_(3)C_(2)T_(x)-MXene is 1.0 mg/mL,the ILSS of the HMCF/EP composites increases by 23.8%to 85.9 MPa.