硫酸环境下电流强度对碳纤维表面电化学活化的影响  

Effect of current intensity on electrochemical activation of carbon fibers surface in sulfuric acid environment

作　　者：马崇攀 张洋[1] 张恒 高爱君 王宇[1,2] MA Chongpan;ZHANG Yang;ZHANG Heng;GAO Aijun;WANG Yu(School of Materials Science and Engineering,Beijing University of Chemical Technology,Beijing 100029,China;Key Laboratory of Carbon Fiber and Functional Polymer,Ministry of Education,Beijing 100029,China)

机构地区：[1]北京化工大学材料科学与工程学院,北京100029 [2]碳纤维及功能高分子教育部重点实验室,北京100029

出　　处：《复合材料学报》2024年第4期1788-1797,共10页Acta Materiae Compositae Sinica

摘　　要：碳纤维的碳含量在90%以上,表面惰性强,表面活化处理是其制备过程中的重要工艺。研究采用XPS、Raman、动态接触角、单丝拉伸和界面剪切强度等测试方法,借助非接触式阳极氧化装置,明确了稀H2SO4作为电解液时电流强度对电化学活化碳纤维表面结构和性能的影响。结果表明:活性氧[O]进攻碳纤维表面使其含氧活性官能团含量增加,在本研究范围内电流越大活化效果越显著;处于阳极附近的碳纤维,受静电与扩散作用影响,SO_(4)^(2−)和S_(2)O_(8)^(2−)进入碳结构内部间隙,碳纤维表面S/C升高,直径增大。在SO_(4)^(2−)刻蚀作用下,碳纤维表面无序碳结构脱落而缺陷减少,石墨化程度降低;SO_(4)^(2−)和S_(2)O_(8)^(2−)插层进入碳结构内部,通过静电作用形成缔合结构,在刻蚀和插层的共同作用下,碳纤维的单丝拉伸强度提升,最高提高了16.77%。0.5 A电流处理后,碳纤维表面粗糙度提升,表面可与环氧树脂基体反应的羟基、羧基官能团含量最高,碳纤维表面极性最强,与去离子水的动态接触角由未处理时的89.9°降低到50.6°,相应的复合材料界面剪切强度提高了47.70%。Carbon fibers with a carbon content of over 90%have the characteristic of strong surface inertness,so surface activation treatment is an essential process in their preparation.The effect of current intensity on the physicochemical structure and properties of electrochemically activated carbon fiber surface under dilute H2SO4 electrolyte were explored by XPS,Raman,dynamic contact angle,monofilament tensile strength and interfacial shear strength,and non-contact anodizing device was used.The results show that the content of oxygen-containing functional groups increases by the attack of reactive oxygen[O]on the surface of carbon fibers,and the activation effect is significant with increasing current within the scope of this study.Carbon fibers near the anode are affected by static electricity and diffusion.SO_(4)^(2−)and S_(2)O_(8)^(2−)enter the internal gap of carbon structure,so the surface S/C and diameter of carbon fibers increase.Under the action of SO_(4)^(2−)etching,the disordered carbon structure on the surface of carbon fiber fell off,the degree of graphitization decreases.SO_(4)^(2−)and S_(2)O_(8)^(2−)are intercalated into the carbon structures,forming an associated structure through electrostatic interaction.Under the combined effect of etching and intercalation,the monofilament tensile strength of carbon fibers has been improved,with a maximum increase of 16.77%.After 0.5 A current treatment,the surface roughness of carbon fiber is improved,the content of hydroxyl and carboxyl functional groups on the carbon fiber surface that can react with the epoxy resin matrix is the highest,the surface polarity of carbon fiber is the strongest,the dynamic contact angle with deionized water is reduced from 89.9°of untreated to 50.6°,and the corresponding interfacial shear strength of the composite is increased by 47.70%.

关 键 词：碳纤维 电化学活化 表面结构 稀硫酸 活性氧[O] 

分 类 号：TB332[一般工业技术—材料科学与工程]