Facile synthesis of highly flexible polymethylsilsesquioxane aerogel monoliths with low density, low thermal conductivity and superhydrophobicity

doi:10.1016/j.vacuum.2020.109825

Vacuum

Volume 183, January 2021, 109825

https://doi.org/10.1016/j.vacuum.2020.109825 Get rights and content

Highlights

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The gelation process of co-precursors can be quickly completed within 15 min.
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PMSAs exhibited low density, low thermal conductivity and superhydrophobicity.
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PMSAs showed excellent compressibility and bending flexibility.

Abstract

In the present work, a facile method was proposed to synthesize highly flexible polymethylsilsesquioxane aerogel (PMSA) monoliths by adopting methyltrimethoxysilane (MTMS) and dimethyldimethoxysilane (DMDMS) as co-precursors and ammonia as a base catalyst. The sol-gel process can be completed within 15 min, and gels were directly dried by ambient pressure drying to obtain monolithic PMSAs. The PMSA had low density (as low as 0.087 g cm⁻³), high porosity (90.6–94.5%), macro-pore structure and low thermal conductivity (0.0321–0.0384 W m⁻¹ K⁻¹). Moreover, excellent compressibility and bending flexibility, together with superhydrophobicity (a contact angle was 162°) were achieved. This work provides an attractive strategy to synthesize highly flexible monolithic PMSAs as promising materials for thermal insulation applications.

Section snippets

Declaration of competing interest

The authors declare that they have no known competing financialinterestsor personal relationships that could have appeared to influence the work reported in this paper.

Acknowledgments

This work was supported by Open Project of State Key Laboratory of Advanced Special Steel,Shanghai Key Laboratory of Advanced Ferrometallurgy, Shanghai University (SKLASS 2019–04), Science and Technology Commission of Shanghai Municipality (No. 19DZ2270200) and Natural Science Foundation of Jiangsu Province (Grant No. BK20191051).

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View full text

Facile synthesis of highly flexible polymethylsilsesquioxane aerogel monoliths with low density, low thermal conductivity and superhydrophobicity

Highlights

Abstract

Section snippets

Declaration of competing interest

Acknowledgments

Build. Environ.

Vacuum

Mater. Lett.

Micropor. Mesopor. Mater.

J. Non-Cryst. Solids

Nanostruct. Mater.

Angew. Chem. Int. Ed.

J. Porous Materi.

Langmuir

J. Mater. Chem. A

Adv. Mater.