RU2330052C1 - Aquatic water-repelling composition - Google Patents

Abstract

FIELD: physics.

SUBSTANCE: invention concerns water-repelling compositions applied in providing air- water- and frost-resistance to natural and artificial contruction materials, and in imparting water-repellent properties to sorbents used for oil spill liquidation. The offered water-repelling composition contains (mass %) sodium alkyldihydrosiliconate (78.3-81.3) and sodium or potassium silicate (10.2-18.0) substrate, with addition of product of interaction between alkylpolyhydridsiloxane with non-organic aprotic acid (0.72-11.5) taken in the ratio of 1:0.44 to 1:0.57. Boric or orthophosphoric acid is used in the composition as non-organic aprotic acid.

EFFECT: tolerance to carbon acid in the air or water, long-term water-repelling effect on the surface of material processed.

2 cl, 1 tbl, 5 ex

Description

The invention relates to the production of water-repellent (hydrophobic) compositions for imparting weather, water and frost resistance to various materials, such as cardboard, as well as products from concrete and limestone, as well as hydrophobization of sorbents to eliminate accidental spills of oil and oil products from the surface of the earth or water.

A well-known group of water-repellents based on water-soluble organosilicon compounds sold by the domestic industry under the trademarks GKZH-10, GKZH-11, GKZH-11 M and other modifications used in construction to protect buildings from moisture is known (V.M. .Trofimov, V.M.Movchanyuk. Hydrophobic protection of building materials, structures, buildings and internal premises. St. Petersburg, 1997, p.7).

The main disadvantage of such water repellents is that the process of transition to the liquid phase (water) is reversible, namely, after water has dried from the surface of the material, subsequent abundant wetting of the surface leads to leaching of the organosilicon compound.

In addition, during atmospheric exposure in the form of an air-vapor phase on the surface treated with such water repellents, the organosilicon carbonization occurs mainly under the influence of CO ₂ contained in the air, followed by moisture penetration into the inner layers of the material, this necessitates the renewal of the surface by periodic processing it with fresh portions of such water repellents.

Known aqueous hydrophobic composition obtained by mixing an alkali metal alkylsiliconate, a water-soluble alkali metal silicate and an inorganic acid (US 2441422, M. CL 106-634, publ. 1946). In this case, sulfuric acid is mainly used as the inorganic acid.

Known water-repellent composition is a gel-like composition with a pH of 3-8, and when used to process materials from the surface, it does not penetrate into the materials, which does not allow imparting water-repellent properties to materials for a long time.

The scope of such a water repellent is limited.

The closest analogue of the invention is an aqueous hydrophobic composition based on sodium dihydrosiliconate and sodium silicate and / or potassium (RU 2093630, M. CL D21H 21/16, C09D 1/04, publ. 20.10.97).

At the same time, sodium methyl dihydrosiliconate is used as sodium methyl or ethyl dihydrosiliconate, and before mixing with sodium and / or potassium silicate, sodium alkyl dihydrosiliconate is mixed with phosphoric and / or boric acid.

The known composition is characterized by the ability to deeply impregnate materials, providing a hydrophobic effect for a long time.

However, such a water repellent does not provide the necessary resistance to materials to the action of carbon dioxide.

A new technical result of the present invention is the creation of a water repellent resistant to the action of carbon dioxide in air or water, and providing a water-repellent effect on the surface of the processed material for more than 10 years.

This technical result is achieved by the fact that the aqueous hydrophobizing composition based on sodium dihydrosiliconate and sodium silicate and / or potassium further comprises the product of the interaction of sodium alkyl polyhydride siloxane with inorganic aprotic acid in a ratio of 1: 0.44 to 1: 0.57 and the following ratio of components (wt.%): sodium alkyldihydrosiliconate 78.3-81.3; sodium and / or potassium silicate 10.2-18.0; the product of the interaction of alkylpolyhydridesiloxane with inorganic aprotic acid 0.72-11.5. In this case, the aqueous hydrophobizing composition contains boron or phosphoric acid as an inorganic aprotic acid, and contains hydrophobizing liquids GKZh-10 or GKZh-11, produced respectively according to GOST 13032-77 and TU 6-02-604-76, as inorganic aprotic acid; as alkylpolyhydridesiloxane contains K-136-46, produced in accordance with GOST 10834-76.

Such surface treatment of materials makes it possible to obtain a treated surface that is very stable in time (life time ~ 10 years) due to resistance to the action of carbon dioxide in air or water.

The proposed hydrophobic composition is obtained using the following mechanism of chemical reactions:

a) mixing K-136-46, which is a product of the formula

where n is the number of units = Si (H) O in the chain (10 <n <15), with phosphoric acid, the product of their interaction is obtained;

b) the resulting product is added with stirring to a mixture containing GKZh-10 or GKZh-11 and Na and / or K silicate; in this case, NaH / or K silicate with an excess of phosphoric acid forms a mixture of sodium (potassium) phosphate salts (NaHPO ₄ , Na ₂ PO ₃ , etc.), which, interacting with GKZh-10 or GKZh-11, form a mixture of Na phosphorus silicates (or to).

The present invention is illustrated by the following examples 1-5 are presented in the table.

The aqueous hydrophobic composition according to examples 1-4 is tested by applying to cardboard, drying the coating and determining the hydrophobic properties (hydrophobic effect after immersion of the sample in water for 72 hours, wt.%; Capillary suction after processing the product after 72 hours, wt.%). The results are presented in the table.

The aqueous hydrophobic composition of example 5 is tested by applying to a building stone, drying the coating and determining hydrophobic properties (hydrophobic effect after immersion of the sample in water for 72 hours, wt.%; Capillary suction after processing the product after 72 hours, wt.%). The results are presented in the table.

Analysis of the table shows that the hydrophobic effect achieved by the objects (cardboard, building stone) during their processing by the proposed hydrophobic composition is significantly higher than in the prototype (example 6).

In this case, the capillary suction by objects during their processing by the proposed hydrophobizing composition is significantly lower than that of the object treated with a hydrophobizing agent according to the prototype, which is achieved by finding in the processed volume objects of complex composition containing both a mixture of Na (or K) phosphorsilicates and a mixture of interaction products K-136-46 with phosphoric acid.

Thus, the proposed water repellent provides a more stable surface to the action of carbon dioxide in the air or in water, and provides the surface with a water-repellent effect for a longer period (more than 10 years).

Composition of water repellent and hydrophobic effect No. n / a examples Composition Components Depth of impregnation, mm Hydrophobic effect Alkyl (ethyl) polysiloxane hydride liquid K-136-41, wt.% Inorganic aprotic acid The ratio of alkyl (ethyl) polysiloxane to inorganic. aprotic acid Alkyl dihydrosiliconate Na, GKZh-11, wt.% Silicate of sodium / potassium, wt.% The product of the interaction, wt.% After immersion of the sample in water for 72 hours, wt.% Capillary suction treatment of the product after 72 hours, wt.% Phosphoric, wt.% boric, wt.% one 0.5 0.22 - 1: 0.44 81.28 18.0 0.72 3 1.8 1.7-1.8 2 0.9 - 0.39 1: 0.43 81.11 17.6 1.29 four 1.7 1.5-1.7 3 1.3 0.56 - 1: 0.41 80.94 17,2 1.86 four 1,6 1.6-1.8 four 5,0 2.17 - 1: 0.43 79.33 13.5 7.17 5 1,2 1.2-1.3 5 7.3 4.2 - 1: 0.57 78.3 10,2 11.5 6 0.7 0.8-1.0 6 prototype no 4.2 - - 77.3 18.5 - 6-7 3.0 2.0-2.7

Claims (2)

1. An aqueous hydrophobizing composition based on sodium dihydrosiliconate and sodium silicate and / or potassium, characterized in that it further comprises the product of the interaction of alkyl polyhydride siloxane with inorganic aprotic acid in a ratio of 1: 0.44 to 1: 0.57 and the following ratio of components , in wt.%: sodium alkyl dihydrosiliconate 78.3-81.3 sodium and / or potassium silicate 10.2-18.0 product of the interaction of alkylpolyhydridesiloxane with inorganic aprotic acid 0.72-11.5 2. The aqueous hydrophobizing composition according to claim 1, characterized in that it contains boric or phosphoric acid as an inorganic aprotic acid.