Abstract
This paper is devoted to an overview of the main ways of creating porous composite materials. Porous materials are solids containing free space in the form of cavities, channels, or pores, which determine the presence of an internal interfacial surface. The analysis of the general methods of obtaining porous materials. A deposition is one of the most common methods for producing porous materials. Thermal decomposition, as a method used to obtain porous oxide materials by thermal decomposition of various compounds. Hydrothermal synthesis is widely used to produce zeolites. Selective dissolution of individual components of a substance using chemical reactions is also one of the effective methods for creating or increasing porosity. The paper discusses the methods of forming highly porous refractory materials. There are two main ways of forming refractory ceramic products. The first way is the direct sintering of dispersions of ceramic fibers. The second method is the use of a binder, which can significantly reduce the temperature of obtaining a porous product. The possibilities of obtaining porous nanocomposites based on aerogels are shown. Composite materials are usually obtained by combining two different materials. In general, the creation of composites is used to take advantage of each type of material and to minimize their disadvantages. Aerogels are fragile substances. But with the introduction of another component into their structure, it is possible to increase the strength of the material. Such materials have the desired optical properties, high surface area, and low density like silica aerogel. A review of methods for obtaining porous materials using the phenomenon of spinodal decomposition has been carried out. Materials whose structure is formed in microphase separation during polymerization or polycondensation have high permeability and a sufficiently large specific surface. A significant advantage of such materials is high porosity, which can reach 80% or more
Highlights
Porous materials are solids containing free space in the form of cavities, channels, or pores, which determine the presence of an internal interfacial surface
The first way is the direct sintering of dispersions of ceramic fibers
The porous material is a solid body containing in its volume free space in the form of cavities, channels, or pores, which determine the presence of an internal interfacial surface
Summary
The porous material is a solid body containing in its volume free space in the form of cavities, channels, or pores, which determine the presence of an internal interfacial surface. With increasing dispersion, porous bodies are transferred from macroporous bodies to meso- and microporous bodies, in which the pore sizes are comparable with the sizes of molecules In the latter case, and the asymptotic limit, the idea of the inner surface begins to lose its physical meaning, by analogy with true solutions [2]. Membranes with a pore diameter of < 500 nm are considered microporous, and macroporous > 500 nm are microporous This classification is due to differences in the mechanisms of transfer of molecules. In materials with a pore diameter much smaller than the mean free path of molecules, a hydrodynamic process, called the Knudsen flow, is realized. The transfer occurs through a viscous flow of liquid or gas Porous bodies in their structure are divided into corpuscular and spongy. This article is the completion of a series of articles on porous nanomaterials published in the journal “Nanotechnology in Construction” [39–43]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callMore From: Nanotechnologies in Construction A Scientific Internet-Journal
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
