Sorption of Water Vapor Materials of Mineral Wool Products of Modern Manufacture. Part II

The article is devoted to studies of the relationship of sorption humidity with a porous structure on the example of thermal insulation products made of mineral (glass) wool produced by “URSA Eurasia”. Experimental studies of water vapour sorption on the materials of URSA 6 brands of glass wool products of modern production were carried out. The obtained sorption isotherms of all the studied brands were close to each other, and only the maximum sorption humidity significantly differed depending on the brand. The relationship between the sorption of water vapour and density of the product is not installed. It is hypothesized that the sorption of water vapour significantly depends on the content of all organic substances (not only the binder) in the mineral wool. An averaged isotherm of sorption of mineral wool products URSA was constructed, which can be used for calculating the humidity regime of building envelope structures. Based on experimentally obtained sorption isotherms, the specific surface area of the studied materials was determined, and conclusions were made about the predominant role of mesoporisity of glass fiber products in the process of water vapour sorption. The results of the study of structural characteristics can be used in the further study of their impact on the performance of mineral wool products. These aspects will be reflected in the following parts of the work.

V.G. GAGARIN^{1, 2, 3}, Doctor of Sciences, (Engineering), Corresponding Member RAACS (This email address is being protected from spambots. You need JavaScript enabled to view it.);
P.P. PASTUShKOV^{1, 2}, Candidate of Sciences (Engineering) (This email address is being protected from spambots. You need JavaScript enabled to view it.)

¹ Research Institute of Building Physics of the Russian Academy of Architecture and Construction Sciences (21, Lokomotivniy Driveway, Moscow, 127238, Russian Federation)
² Institute of Mechanics Lomonosov Moscow State University (1, Michurinsky Avenue, Moscow, 119192, Russian Federation)3 National Research Moscow State University of Civil Engineering (26, Yaroslavskoe Highway, Moscow, 129337, Russian Federation)

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