碳纳米纤维调控粉煤灰基地质聚合物力学/传感性能优化  

Optimization of mechanical property and sensing performance in CNF/fly ash-based geopolymer composites

作　　者：范兴昊 刘叶帆 张国昊 欧阳静[1,2] 杨华明[1,2] 胡海龙[3] 张帆 FAN Xinghao;LIU Yefan;ZHANG Guohao;OUYANG Jing;YANG Huaming;HU Hailong;ZHANG Fan(School of Minerals Processing and Bioengineering,Central South University,Changsha 410083,China;Hunan Key Laboratory of Mineral Materials and Application,Central South University,Changsha 410083,China;Research Institute of Aerospace Technology,Central South University,Changsha 410083,China)

机构地区：[1]中南大学资源加工与生物工程学院,湖南长沙410083 [2]中南大学矿物材料及其应用湖南省重点实验室,湖南长沙410083 [3]中南大学航空航天技术研究院,湖南长沙410083

出　　处：《中南大学学报（自然科学版）》2024年第3期907-917,共11页Journal of Central South University:Science and Technology

基　　金：国家自然科学基金资助项目(52204299);长沙市自然科学基金资助项目(kq2202093);湖南省自然科学基金资助项目(2022JJ40623,2022JJ30722)。

摘　　要：采用物理混合法向粉煤灰基地质聚合物中加入碳纳米纤维(CNF),制备不同CNF质量分数(0~2.0%)的粉煤灰基地质聚合物复合材料。通过对粉煤灰基地质聚合物复合材料微结构、力学性能、电学性能及传感性能进行研究,揭示CNF调控粉煤灰基地质聚合物力学与传感性能的具体演变规律,并对CNF质量分数为0.5%的复合材料进行循环稳定性实验及方差稳定性量化分析。研究结果表明:当CNF添加量增加时,粉煤灰基地质聚合物的弹性模量和抗弯强度皆显著提升;当CNF质量分数为0.5%和2.0%时,复合材料的弹性模量分别提升到1.35 MPa和0.23 MPa,抗弯强度分别提升到3.9 MPa和0.32 MPa;此外,随CNF质量分数增加,复合材料的电阻率随之降低,当CNF质量分数达到2.0%时,复合材料的电阻率降低到46Ω·m,CNF的添加有利于粉煤灰基地质聚合物导电能力提升;在单向加压实验条件下,当CNF质量分数为0.5%、1.0%和2.0%时,复合材料的传感灵敏度分别为71.56、57.33与25.58,随着CNF的加入量不断增大,粉煤灰基地质聚合物的传感灵敏度先增后减,通过实验判断CNF质量分数阈值可能为0~0.5%。在CNF质量分数为0.5%的条件下,复合材料传感性能相对比较稳定。Fly ash based geopolymer composites with varied CNF mass fractions(0−2.0%)were prepared by adding carbon nanofiber(CNF)to the fly ash based geopolymer via physical mixing method.The microstructure,mechanical property,electrical property and sensing property of the fly ash based geopolymer composites were investigated to reveal the specific effect of CNF mass fraction on the mechanical and sensing properties of this fabricated geopolymer composites,and the composites with CNF mass fraction of 0.5%underwent stability testing,which included a quantitative analysis of their variance stability.The results show that the elastic modulus and flexural strength of the composites increase significantly with the increase of CNF mass fraction.When the CNF mass fractions are 0.5%and 2.0%,the elastic modulus of the composites correspondingly increases to 1.35 MPa and 3.9 MPa,and the flexural strength increases to 0.23 MPa and 0.32 MPa,respectively.In addition,the resistivity of the composite decreases with the increase of CNF mass fraction,the resistivity decreases to 46Ω·m when the CNF mass fraction is up to 2.0%,and the added CNF is beneficial to the enhancement of the conductivity of the ash-based geopolymer composites.At the condition of the unidirectional pressurization experiment,the sensing sensitivity of the composite is 71.56,57.33 and 25.58 when the CNF mass fraction is 0.5%,1.0%and 2.0%,respectively.With the increaes of CNF mass fraction,the sensing sensitivities of the ash-based geopolymer composites firstly increase and then decrease,and the concentration threshold is between 0 and 0.5%.At the condition of CNF mass fraction of 0.5%,the sensing performance of the composites is relatively stable.

关 键 词：地质聚合物 碳纳米纤维 传感性能 健康监测 

分 类 号：TB332[一般工业技术—材料科学与工程] TD985[矿业工程—选矿]