深圳大学学报理工版

为研究氧化石墨烯(graphene oxide, GO)对水泥基复合材料路用性能的影响,制备了含不同质量分数GO的改性水泥基复合材料.采用流动度、强度和抗冻性等指标评价GO水泥基复合材料路用性能,结合扫描电镜(scanning electron microscope, SEM)与X射线衍射(X-ray diffraction, XRD)试验探究其改性机理.结果表明,GO改性水泥基复合材料力学性能和抗冻性增幅较大,流动度有所下降; GO质量分数为0.04%时,水泥基复合材料的强度最高,其28 d抗压与抗折强度较GO质量分数为0的对照组分别提高了31.3%与44.2%; GO质量分数为0.02%时,抗冻性最好,冻融循环300 次后,质量损失率仅为0.6%,残留抗压与抗折强度比分别为69%和75%.微观分析可知,GO表面的含氧亲水基团(羟基、羧基等)可为水泥水化产物结晶提供生长点,硅酸钙凝胶(C-S-H)在其上生长、交联,并且随水化龄期增长交联作用日益增强,GO可以改善水泥基复合材料的力学性能和抗冻性.

In order to investigate the effect of graphene oxide(GO)on the pavement performance of cement-based composites,modified cement-based composites with different content of GO were prepared,and the pavement performance was evaluated by the fluidity,strength and frost resistance.The modification mechanism was investigated by scanning electron microscope(SEM)and X-ray diffraction.The results show that the mechanical properties and frost resistance of GO modified cement-based composites increase greatly and the fluidity decreases.When the content of GO is 0.04%(by mass),the strength of cement-based composites is the highest, and the compressive and flexural strength of the composites at 28 d increase by 31.3% and 44.2% compared with the group with the content of GO of 0.When the content of GO is 0.02%,the cement-based composites have the best frost resistance.After 300 cycles of freezing-thawing,the mass loss rate is only 0.6% as well as the residual compressive strength ratio and residual flexural strength ratio are 69% and 75% respectively.According to the micro-analysis,oxygen-containing hydrophilic groups(hydroxyl group,carboxyl group,etc)on the GO surface can provide growing points for the crystallization of cement hydration products and the calcium silicate gel(C-S-H)grows and cross-links on it and the effect of cross-linking increases with the hydration age.GO can improve the mechanical properties and frost resistance of cement-based composites.

引言
1 试验研究
2 试验结果及分析
3 结论

图1 GO和石墨烯微观形貌<br/>Fig.1 Microscopic image of GO and graphene

图1 GO和石墨烯微观形貌
Fig.1 Microscopic image of GO and graphene

图2 石墨烯和GO XRD图像<br/>Fig.2 XRD images of graphene and GO2d sin θ=nλ(1)

图2 石墨烯和GO XRD图像
Fig.2 XRD images of graphene and GO2d sin θ=nλ(1)

表1 不同GO掺量的水泥基复合材料流动度<br/>Table 1 Fluidity of cement-based composites with different contents of GO

表1 不同GO掺量的水泥基复合材料流动度
Table 1 Fluidity of cement-based composites with different contents of GO

图3 7 d和28 d砂浆强度测试结果<br/>Fig.3 Strength of mortar at 7 d and 28 d

图3 7 d和28 d砂浆强度测试结果
Fig.3 Strength of mortar at 7 d and 28 d

图4 28 d折压比<br/>Fig.4 Ratio of flexural strength to compressive strength at 28 d

图4 28 d折压比
Fig.4 Ratio of flexural strength to compressive strength at 28 d

表2 冻融循环后的质量损失率<br/>Table 2 Quality loss after freeze-thaw cycles%

表2 冻融循环后的质量损失率
Table 2 Quality loss after freeze-thaw cycles%

表3 不同冻融次数下的相对动弹性模量<br/>Table 3 Relative dynamic elastic modulus after different freeze-thaw cycles%

表3 不同冻融次数下的相对动弹性模量
Table 3 Relative dynamic elastic modulus after different freeze-thaw cycles%

表4 残留抗压强度与抗折强度<br/>Table 4 Residual compressive strength and flexural strength

表4 残留抗压强度与抗折强度
Table 4 Residual compressive strength and flexural strength

图5 GO的SEM图像
Fig.5 SEM images of GO

图6 不同龄期的水泥净浆SEM图像(30 000×)<br/>Fig.6 SEM images of cement paste at different ages(30 000×)

图6 不同龄期的水泥净浆SEM图像(30 000×)
Fig.6 SEM images of cement paste at different ages(30 000×)

表5 Spot1和Spot2处各元素含量百分比<br/>Table 5 Content percentage of each element at Spot1 and Spot2%

表5 Spot1和Spot2处各元素含量百分比
Table 5 Content percentage of each element at Spot1 and Spot2%

图7 水泥净浆XRD图像<br/>Fig.7 XRD images of cement paste

图7 水泥净浆XRD图像
Fig.7 XRD images of cement paste

[1] 陈宝锐,吴其胜,诸华军,等.石墨烯/水泥基复合材料的制备与性能[J].材料科学与工程学报,2018,36(4):650-655.
[2] LU Zeyu, LI Xiangyu, HANIF A, et al. Early-age interaction mechanism between the graphene oxide and cement hydrates[J].Construction and Building Materials,2017,152:232-239.
[3] YANG Haibin,MONASTERIO M,CUI Hongzhi,et al.Experimental study of the effects of graphene oxide on microstructure and properties of cement paste composite[J].Composites:Part A,2017,102:263-272.
[4] 马颖,王丹,王晴.多壁碳纳米管水泥基复合材料的制备与力学性能研究[J].混凝土,2014(6):72-74.
[5] MAKAR J M,BEAUDOIN J J.Carbon nanotubes and their application in the construction industry[J].Special Publication-Royal Society of Chemistry,2004,292:331-342.
[6] WANG Qin, WANG Jian, LU Chunxiang, et al. Influence of graphene oxide additions on the microstructure and mechanical strength of cement[J]. New Carbon Materials, 2015,30(4):49-56.
[7] LI Xueguang,WEI Wei,QIN Hao,et al.Co-effects of graphene oxide sheets and single wall carbon nanotubes on mechanical properties of cement[J].Journal of Physics and Chemistry of Solids,2015,85:39- 43.
[8] 吕生华,孙婷,刘晶晶,等.氧化石墨烯纳米片层对水泥基复合材料的增韧效果及作用机制[J].复合材料学报,2014,31(3):644- 652.
[9] 王琴,李时雨,王键,等.氧化石墨烯对水泥水化进程及其主要水化产物的影响[J].硅酸盐学报,2018,46(2):163-172.
[10] BABAK F, ABOLFAZL H, ALIMORAD R, et al. Preparation and mechanical properties of graphene oxide:cement nanocomposites[J].The Scientific World Journal,2014(4):276-323.

备注

引言

1 试验研究

2 试验结果及分析

3 结论

期刊信息

备注

引言

1 试验研究

2 试验结果及分析

3 结 论

期刊信息

3 结论