多壁羧基化碳纳米管改性水泥砂浆抗氯离子渗透性能研究

Study on Chloride Resistance of Cement Mortar Modified with Multi-walled Carboxylated Carbon Nanotubes

研究了一种多壁羧基化碳纳米管(CNT-COOH)对水泥砂浆抗氯离子渗透性能的影响。为了得到均匀的悬浮液,将CNT-COOH分散在蒸馏水中,再进行超声波处理。分别按水泥质量的0.01%、0.05%和0.10%的CNT-COOH进行配合设计,制备了水泥砂浆试件,并根据RCM法测定了氯离子扩散系数。结果表明:当CNT-COOH掺量从0.01%增加至0.05%,氯离子扩散深度和扩散系数均增加;但CNT-COOH掺量继续增加至0.10%时,氯离子扩散深度和扩散系数大幅下降。此外,压汞试验结果表明,当CNT-COOH掺量为0.10%时,CNT-COOH通过消除大孔和降低孔隙率细化了孔径,使得水泥砂浆的微观结构更加密实。

The effect of multi-walled carboxylated nanotubes(CNT-COOH)on chloride resistance of cement mortar was studied.In order to obtain a uniform suspension,CNT-COOH was well-dispersed in distilled water and then treated by ultrasonic.The mix proportion of the cement mortar with 0.01%,0.05%and 0.10%of the cement quality was design,and the chloride diffusion coefficient was determined by the RCM method.The results show that with the increase of CNT-COOH content from 0.05%to 0.05%,the diffusion depth and diffusion coefficient of chloride ion increase,and continuing to increase CNT-COOH content to 0.10%,the diffusion coefficient of chloride has dropped drastically.The results of MIP show that when the CNT-COOH content is 0.10%,CNT-COOH can refine the pore distribution by eliminating the large pore and reducing the porosity,which makes the microstructure of cement mortar compact.