Quantum chemical simulation of surface hydrophobization of silicate materials with alkali siliconates
Abstract
The method of density functional theory was used to study the interaction between methylsilicate CH3Si(OH)2O– or phenylsilicate C6H5Si(OH)2O– anions and silica surface. The probability of these processes was estimated on the basis of analysis of the calculated energy characteristics. The reactions of formation of both methylsilicic and phenylsilicic aсids from their anions in the presence of carbon dioxide for binding hydroxide ions as hydrocarbonate ones are promoted by anion hydration (the energy effects are –61 and –46 kJ/mol respectively). The condensation of methylsilicic acid with silanol groups of silica surface is more effective than that of phenylsilicic one (the energy effects are –36 and –26 kJ/mol respectively).References
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