Bi Cheng, Yang Mingyang, Yang Xu, Yun Ke, Lu Yuan, Zhang Ying, Zheng Jie, Du Mu
Xi'an Special Equipment Inspection Institute, Xi'an 710065, China.
School of Resources Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
Gels. 2025 Mar 6;11(3):184. doi: 10.3390/gels11030184.
The mechanical stability of carbon aerogels, particularly their thermal insulation performance, is closely linked to their elastic modulus. This property plays a crucial role in determining the material's overall mechanical stability. The objective of this study is to enhance the accuracy of elastic modulus predictions for carbon aerogels using a power-scaling model. By setting the prefactor of the Gibson and Ashby equation to 1.0, accurate predictions of the elastic modulus can be achieved if the correct scaling exponent is determined. Twelve sets of experimental data were used to fit the power-scaling model, revealing that the scaling exponent for the elastic modulus of carbon aerogels typically falls between 2.2 and 3.0. This range is narrower than the 2.0 to 4.0 range reported in the literature, with a median value of 2.6 providing reliable predictions. Additionally, a relationship between the solid thermal conductivity and the elastic modulus of carbon aerogels was established using a thermal conduction model. The study also examined the elastic modulus of carbon nanotube and graphene aerogels-both allotropes of carbon aerogel. By fitting experimental data into the power-scaling model, the scaling exponents for carbon nanotube aerogels and graphene aerogels were found to range from 2.7 to 3.5 and 2.7 to 3.7, respectively. Median exponent values of 3.1 and 3.2 were identified as optimal for predicting the elastic moduli of carbon nanotube and graphene aerogels.
碳气凝胶的机械稳定性,尤其是其隔热性能,与它们的弹性模量密切相关。这一特性在决定材料的整体机械稳定性方面起着至关重要的作用。本研究的目的是使用幂次缩放模型提高碳气凝胶弹性模量预测的准确性。通过将吉布森和阿什比方程的前置因子设为1.0,如果确定了正确的缩放指数,就能实现对弹性模量的准确预测。使用十二组实验数据来拟合幂次缩放模型,结果表明碳气凝胶弹性模量的缩放指数通常在2.2至3.0之间。这个范围比文献报道的2.0至4.0范围更窄,中位数为2.6时能提供可靠的预测。此外,利用热传导模型建立了碳气凝胶的固体热导率与弹性模量之间的关系。该研究还考察了碳纳米管气凝胶和石墨烯气凝胶(均为碳气凝胶的同素异形体)的弹性模量。通过将实验数据拟合到幂次缩放模型中,发现碳纳米管气凝胶和石墨烯气凝胶的缩放指数分别在2.7至3.5和2.7至3.7之间。确定中位数指数值3.1和3.2为预测碳纳米管气凝胶和石墨烯气凝胶弹性模量的最佳值。