| Summary: | This study deals with the issue of caking of mineral binding materials during storage and transportation. The author conducted a critical analysis of known methods for the protection of cement from exposure to moisture and water vapour. Common disadvantages of these methods are their low effectiveness and complexity of use in industrial and domestic environments. This article introduces a new method for hydrophobising construction materials using peat, which achieves high water repellency in the modified materials with relatively low expenditure on organic materials. The author proposes film coating of the mineral particles of dispersed hydrophilic materials as a protection mechanism against their undesirable exposure to moisture during storage. The insulating film consists of hydrophobic products (bitumens) released during thermal decomposition of the organic matter in peat. The estimated thickness of the bitumen film is about 12 nm and it does not adversely affect the flow properties of the powder. A model of the formation of film coatings on mineral particles is provided and their elemental chemical composition is determined. It is shown experimentally that the modified hydrophobic cement is protected from exposure to liquid vapours, and optimal values of organic component concentrations in the dispersed mineral matter that do not reduce the strength of cement mortar are identified.
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