Silica-Based Aerogels with Tunable Properties: The Highly Efficient BF3-Catalyzed Preparation and Look inside Their Structure

Silica-Based Aerogels with Tunable Properties: The Highly Efficient BF3-Catalyzed Preparation and Look inside Their Structure Full article

Journal

Macromolecules
ISSN: 0024-9297 , E-ISSN: 1520-5835

Output data

Year: 2021, Volume: 54, Number: 4, Pages: 1961-1975 Pages count : 15 DOI: 10.1021/acs.macromol.0c02598

Authors

Kholodkov Dmitry N. ¹ , Arzumanyan Ashot V. ¹ , Novikov Roman A. ^2,3 , Kashin Alexey S. ² , Polezhaev Alexander V. ^1,4 , Vasil’ev Viktor G. ¹ , Muzafarov Aziz M. ^1,5

Affiliations

1	A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences, 28 Vavilov St., Moscow 119991, Russian Federation
2	N.D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, 47 Leninsky Pr., Moscow 119991, Russian Federation
3	V.A. Engelhardt Institute of Molecular Biology, Russian Academy of Sciences, 32 Vavilov St., Moscow 119991, Russian Federation
4	N.E. Bauman Moscow State Technical University, 5 Baumanskaya 2-ya St., Moscow 105005, Russian Federation
5	N.S. Enikolopov Institute of Synthetic Polymeric Materials, Russian Academy of Sciences, 70 Profsoyuznaya St., Moscow 117393, Russian Federation

This work presents a solution to one of the most fundamentally and practically important challenges in the production of silica-based aerogels, time consumption and expensiveness of these processes, with the main focus on the sol–gel process. We suggested a highly efficient BF3-catalyzed method for the production of aerogels, which allows one to shorten the stage of the formation of a (wet) gel to 5 min, the stage of gel aging to 0, while the stage of gel workup is not required; the duration of these stages, according to the literature, ranges from days to weeks. The process is performed using commercially available, simple, and inexpensive reagents and under mild reaction conditions: BF3·Et2O as the catalyst, acetone as the solvent, room temperature, and at atmospheric pressure. This approach allows one to quickly obtain both classic opaque and transparent silica-based aerogels from Si(OMe)4 or Si(OEt)4 as well as transparent superhydrophobic ones from their mixtures with MeSi(OMe)3 or Me2Si(OMe)2. In addition, we succeeded in obtaining a series of aerogels with various organic and inorganic additives, in particular, in this way, luminescent and metallasiloxane ones were prepared. Also, the effect of the method for producing silica-based aerogels on their (supra)molecular structure and morphology was thoroughly studied by a set of physicochemical methods of analysis: scanning electron and light microscopy, X-ray microtomography, and NMR experiments. These findings allow to tune the density, transparency, mechanical strength, hydrophobicity, and other properties depending on the need by choosing the right technique.

Kholodkov D.N. , Arzumanyan A.V. , Novikov R.A. , Kashin A.S. , Polezhaev A.V. , Vasil’ev V.G. , Muzafarov A.M.
Silica-Based Aerogels with Tunable Properties: The Highly Efficient BF3-Catalyzed Preparation and Look inside Their Structure
Macromolecules. 2021. V.54. N4. P.1961-1975. DOI: 10.1021/acs.macromol.0c02598 WOS Scopus OpenAlex

≡ Web of science:	WOS:000623052700038
≡ Scopus:	2-s2.0-85101553037
≡ OpenAlex:	W3127100489