Original title: Hydrofobizace pískovcových vápencových materiálů s tenkou hydrofilní povrchovou vrstvou
Translated title: Hydrophobization of sandstone and limestone materials with a thin hydrophilic coating
Authors: Rathouský, Jiří
Document type: Methods
Year: 2015
Language: cze
Abstract: [cze] [eng]
Podle Památkového postupu hydrofobizace s tenkou hydrofilní povrchovou vrstvou lze ošetřovat nejrůznější materiály běžně používané v památkářské praxi v různých obdobích, je rozsah uživatelů značně široký. Rozsah aplikací zahrnuje artefakty z kamene různé povahy (pískovce, vápence, opuky) i vnější povrchy budov. Uživateli mohou být jednotliví restaurátoři i stavební firmy. Hydrophobization of the surface of sandstone and limestone materials is an effective method of their protection against the effects of weathering. Effective hydrophobizing agents are solutions of alkyltrialkoxysilanes, especially methyl- or octyltriethoxysilane in a suitable organic solvent (in particular white spirit), and solutions containing polymeric organosilicon compounds also in mineral spirits. It is a major disadvantage of hydrophobization that there is a change in the original appearance of the material due to the increased deposition of dirt on the hydrophobic surface, which is unevenly washed away by rain water, which results in unsightly stains on the surface. Another general disadvantage of hydrophobization is that it renders it very difficult to impossible to carry out another treatment particularly with hydrophilic agents. With the proposed method it is possible to create a thin hydrophilic layer on a hydrophobized surface to ensure the uniform washing away of dirt and to enable the mentioned additional surface treatment. Given that the depth of its removal may be precisely controlled in this process, the hydrophobization will be removed only to the desired depth and will not therefore undermine the effectiveness of the hydrophobization. The new method of hydrophobization of sandstone and limestone materials with a thin hydrophilic coating is based on a two-step process comprising the surface hydrophobization using an agent comprising alkyltrialkoxysilanes or polydimethylsiloxane polymers in an organic solvent to a sufficient depth, and the removal of a thin surface layer of the hydrophobization, bound to the surface of the material, with a thickness of approximately 1 mm.
Keywords: Hydrophobization; sandstone and limestone materials; surfaces
Project no.: DF11P01OVV012 (CEP)
Funding provider: GA MK

Institution: J. Heyrovsky Institute of Physical Chemistry AS ČR (web)
Document availability information: Fulltext is available at the institute of the Academy of Sciences.
Original record: http://hdl.handle.net/11104/0252439

Permalink: http://www.nusl.cz/ntk/nusl-201146


The record appears in these collections:
Research > Institutes ASCR > J. Heyrovsky Institute of Physical Chemistry
Analytical and methodological materials > Methods