RU2422264C1 - Water-based silicon impregnating compound for wood - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to protective compositions for wood and can be used in biological protection of building structures and articles made from wood. The compositions can also be used as an impregnating or finishing agent for concrete, foamed concrete, brick, asbestos board or gypsum. The impregnating compound contains polymethylphenyl siloxane or polyphenylsiloxane resin in form of a solution in an aromatic solvent, an acrylate copolymer, butyl alcohol, white spirit and water. The components are in the following ratio in vol. %: resin 30.0-45.0, butyl alcohol 6.0-15.0, acrylate copolymer 0.5-2.0, white spirit 10.0-20.0, water - the rest. The impregnating compound can also contain a biocidal additive which is compatible with organosilicon and acrylate polymers in amount of up to 0.1 vol. %.

EFFECT: obtained coatings do not hinder normal air exchange of structures, do not change the appearance of material; after treatment, building structures acquire hydrophobic and anti-fungus properties and become resistant to moss and lichen.

2 cl, 2 tbl, 9 ex

Description

The invention relates to protective compositions for wood and can be used for bioprotection of building structures and wood products. It can also be used as an impregnating and finishing agent for concrete, foam concrete, brick, slate, gypsum. A necessary condition for increasing the service life of building materials from wood and other building products is their protection from the influence of natural atmospheric factors: temperature, humidity, ultraviolet and infrared radiation, biodeterioration.

Currently, various compositions are known on bitumen, polymer and mixed substrates, which are applied to the surface of concrete, brick, gypsum, asbestos cement, slate, wood in order to protect them from destruction.

However, materials based on oil, pentaphthalic, glyphthalic and other polymeric binders, as well as binders of petroleum origin are not weather resistant. Coatings based on epoxy binders are devoid of these drawbacks, but they do not have sufficient manufacturability, as they are two-component and do not penetrate deep into the coated material (V.V. Chebotarevsky. Varnishes and paints - what is it. - M .: Chemistry, 1983 .).

The indicated disadvantages are deprived of organosilicon resins used as the basis for varnishes and paints in various industries. Their distinctive feature is high acid resistance, alkali resistance, resistance to ultraviolet and infrared radiation. In addition, organosilicon varnishes, paints and impregnations based on them have exceptional hydrophobizing ability. When wooden structures are impregnated on the outside and inside the wood, a polymer film is created that is not subject to decay, since organosilicon compounds are antiseptics due to the structure of the molecules. Based on organosilicon compounds, many varnishes and enamels are known. One of the most common enamels is facade enamel brand KO-174. The disadvantages of the KO-174 enamel include its shallow penetration into the surface during painting due to the presence of fillers and pigments in its composition, as well as the increased viscosity of its varnish base (M.V.Sobolevsky. Properties and applications of organosilicon products. - M .: Chemistry, 1975).

A known composition for coating building elements, including in wt.%: Butadiene - styrene latex SCS 65GP 17-19; 4% aqueous solution of sodium salt of carboxymethyl cellulose (CMC) 0.12-0.28; methyl (ethyl) siloxane - 1.17-1.4; 5% solution of polyethylene ethers of alkyl phenols 0.08-0.1; filler (chalk, talc, marshalite) 14 17; 25% solution of rosin in acetone 4.9-4.5 and alkanol stabilized 30% aqueous emulsion of polymethylsiloxane liquid 0.28-0.35 (SU No. 732315, CL 04B 25/02, prior. 1980).

However, coatings based on such a composition have significant water absorption, quickly lose their adhesive properties and appearance under the influence of high humidity and temperature. In addition, the composition is multicomponent and difficult to prepare, which greatly limits its use.

A known composition for the impregnation of building materials containing an organosilicon compound, isopropyl alcohol, sodium hydrogen sulfate and water (SU 1735252, IPC С04В 41/64, prior. 05.21.1990, publ. 23.05.1992). The material impregnated with this composition acquires hydrophobization and mushroom-resistant properties.

Known means for protecting wood from biodegradation of fungal species based on 5-32% acetone or alcohol solution of polymer products of incomplete acid hydrolysis of tetraethoxysilane (RU 2014995, IPC B27K 3/34, prior. 02.25.1991, publ. 30.06.1994).

The closest in composition to the present invention is a composition based on polymethylphenylsiloxane resin containing an organosilicon base and toluene, with organic solvents in the form of methyl or ethyl or isopropyl alcohols in the following ratio of components, vol.%:

Specified Organic Solvent 50-75 Organosilicon resin 25-50

This composition can be used as an antiseptic for wood impregnation. The latter acquires hydrophobic and mushroom-resistant properties (RU 2164505, С04В 41/84, prior. 06/01/1999, publ. 03/27/2001).

The technical task of the invention is to expand the range of highly effective means for protecting wood.

This problem is solved in that the impregnation for wood contains polymethylphenylsiloxane or polyphenylsiloxane resin in the form of a solution in an aromatic solvent, an acrylate copolymer, white spirit, butyl alcohol and water in the following ratio of components, vol.%:

Specified Resin 30-45 Butyl alcohol 6.0-15.0 Acrylate copolymer 0.5-2.0 White Spirit 10.0-20.0 Water rest

The proposed composition may additionally contain a biocidal additive compatible with organosilicon and acrylate polymers, in an amount up to 0.1 vol.%.

In the following examples, a polymethylphenylsiloxane resin (PMFSS) was used, which is a 50-60% solution of polymethylphenylisobutoxysiloxane resin in toluene or xylene (TU 2228-277-05763441-99). As the polyphenylsiloxane resin used organosilicon resin KO 134-276, which is a 34-40% solution of polyphenylsiloxane resin in toluene or xylene (TU 2228-463-05763441-2005), and organosilicon resin 139-297, which is a 60-70% solution polyphenyl isobutoxysiloxane resin in toluene or xylene (TU 2228-440-05763441-2004).

As the acrylate copolymer, a BMK-5 copolymer was used, which is a copolymer of butyl methacrylate and methacrylic acid, a bead polymer based on butyl methacrylate and methyl methacrylate, DEGALAN LP65 / 12, styrene acrylic dispersion.

As a biocidal additive, Triamine Y12D (substance) manufactured by Akzo-Nobel (Netherlands), based on dodecyldipropylene triamine, was used, but any biocidal additive compatible with organosilicon and acrylate polymers is allowed.

The impregnation is prepared as follows: the calculated amount of acrylate copolymer is dissolved in the calculated amount of alcohol and white spirit, then the remaining ingredients are subsequently loaded, the mixture is stirred until a homogeneous emulsion is formed. The proposed silicone impregnation is used to give the wood mushroom resistance, moisture resistance, weather resistance and increase strength and durability. Apply the composition with a brush, roller, spray or dipping.

Coatings based on the proposed silicone impregnation do not interfere with the normal air exchange of structures, do not change the appearance of the material, increase its service life, and also prevent the reduction of thermal insulation properties of the material, have good resistance to various factors in time (alternating freezing and thawing, moistening and drying) , and also resistant to ultraviolet and infrared rays. After processing, building structures are not exposed to the destructive action of mosses and lichens.

Variants of the composition of the proposed impregnation are presented in table 1.

The obtained impregnation options are a milky liquid without mechanical impurities, the mass fraction of non-volatile substances is at least 18%, the conditional viscosity at a temperature of (20 ± 0.5) ° С with a viscometer of the VZ-246 type with a nozzle diameter of 4 mm at least 11 s , drying time to degree 3 at a temperature of (20 ± 2) ° С no more than 1 hour

Tests for mushroom resistance (biostability) were carried out according to GOST 9.048-89, method 1. The composition in two layers was applied with a brush to wooden samples, then dried for 24 hours at room temperature. After that, the samples were infected with a suspension with a concentration of 1-2 million / ml of spores of the fungi Aspergillus niger van Tieghem, Aspergillus terreus Thom, Aureobasidium pullulans (de Bary) Arnaud, Paecilomyces variotii Bainier, Penicillium funiculosum Thom, Penicillium ochrochloruliris beris biormema Pers. ex S.F. Gray. Additionally, spores of wood-destroying fungi Serpula lacrimans VKM F - 465 and Antrodia sinuosa VKM F - 1741 were introduced into the suspension. Wood samples without impregnation were used as control.

Samples infected with a suspension of mushrooms were placed in an open Petri dish in a desiccator and kept under conditions optimal for mushroom growth: temperature 27-28 ° С and 98% humidity for 28 days. Interim examinations of the samples were carried out every 14 days.

The test results are presented in table 2, from which it can be seen that coatings based on the proposed impregnation give wood moisture resistance and mushroom resistance (biostability) of 100%.

Claims (2)

1. Silicone impregnation for wood containing polymethylphenylsiloxane or polyphenylsiloxane resin in the form of a solution in an aromatic solvent, acrylate copolymer, butyl alcohol, white spirit and water, in the following ratio, vol.%:
specified resin 30.0-45.0 butyl alcohol 6.0-15.0 acrylate copolymer 0.5-2.0 White Spirit 10.0-20.0 water rest 2. Silicone impregnation according to claim 1, characterized in that it further comprises a biocidal additive compatible with organosilicon and acrylate polymers in an amount up to 0.1 vol.%.