Waterproofing primer

Abstract

FIELD: primer compositions.SUBSTANCE: waterproofing primer compound is proposed, which includes (wt.%): styrene-acrylic (61.6-66) and polyvinyl acetate (30.4-34) dispersions, dioctyl adipate plasticizer (1.8-2.2) and a water-soluble thickener – acrylic dispersion Novopol 007 (1.8-2.2). After a single application and drying, the composition forms a transparent, adhesively strong and waterproof layer that maintains its seal even after repeated wetting and drying cycles.EFFECT: proposed composition is cheap and applicable for internal and external waterproofing of walls in dry and wet rooms.1 cl, 3 ex

Description

[0001] The invention relates to the repair and construction industry, in particular to compositions for external and internal work as a primer and waterproofing for walls for dry and wet rooms.

[0002] The prior art discloses compositions based on styrene acrylic dispersions, PVA, plasticizers and thickeners that provide waterproofing.

[0003] A PRIMER ADHESIVE COMPOSITION FOR CONSTRUCTION THERMAL INSULATION BOARDS is known (patent RU 2798664, published September 19, 2022). The invention can be used to apply coatings to construction thermal insulation boards. The primer adhesive composition contains a styrene-acrylic dispersion, a polyvinyl acetate dispersion with a dry residue of at least 45%, quartz sand, a 10% polystyrene solution in toluene, a surfactant, and water. The invention improves the adhesion of the primer composition.

[0004] Also known is a COMPOSITION FOR PRODUCING "FLEXIBLE" STONE (patent RU 2809790, published 05 / 13 / 2022). The invention relates to the production of finishing materials, namely materials imitating natural stone. A composition for obtaining a finishing material with the texture of natural stone is described, including acrylic dispersion, dioctyl adipate, polyvinyl acetate (PVA glue) with the addition of marble chips and a coloring pigment, characterized in that styrene-acrylic dispersion arakril STA 5650 is used as an acrylic dispersion, and iron oxide pigment is used as a dye, additionally contains an acrylic thickener and a non-woven fabric in the following ratio of components, wt. %: styrene-acrylic dispersion arakril STA 5650 - 18; dioctyl adipate - 0.54; acrylic thickener - 0.6; polyvinyl acetate (PVA construction) - 9; iron oxide pigment - 0.115; non-woven fabric - 0.3; marble chips - 71.445.The technical result is an improvement in the physical, mechanical and operational properties, leading to an increase in the quality of the finishing material and resistance to weather conditions.

[0005] In the described analogs and prototype, the declared components are either used in different mass ratios, or their technical result—leak resistance—is not confirmed by long-term testing under multiple wetting-drying cycles. After drying, the primer remains opaque or adheres poorly to the wall. In analogs RU 2798664 and RU 2809790, the mass proportions of PVA and acrylic components vary, but do not provide an optimal balance of flexibility and adhesion under prolonged cyclic wetting.

[0006] The objective of the proposed technical solution is to create a composition that combines the functions of a primer and a highly effective waterproofing agent, offering excellent adhesion to the substrate, transparency after drying, and resistance to repeated soaking and drying at a minimal cost. In other words, it is a universal composition.

[0007] The technical result is multifunctionality, including the characteristics of both primer and waterproofing.

[0008] The solution to this problem is achieved due to the fact that the primer-waterproofing contains styrene acrylic dispersion, dioctyl adipate, water-soluble thickener and polyvinyl acetate dispersion, with the following mass ratio of components (wt.%):

[0009] - styrene acrylic dispersion - 61.6-66;

[0010] - dioctyl adipate (DOA) as a plasticizer - 1.8-2.2;

[0011] - acrylic dispersion as a thickener (water-soluble) - 1.8-2.2;

[0012] - polyvinyl acetate dispersion (PVA) - 30.4-34.

[0013] Styrene acrylic dispersion is a substance obtained by mixing styrene and acrylic monomer in an aqueous medium. This dispersion has unique properties and is used in many fields, including construction, industry, textiles, and food. The chemical composition of styrene acrylic dispersion includes styrene and acrylic monomers. Styrene is a colorless liquid with a characteristic odor, used as a monomer in the production of various polymeric materials. Acrylic monomers are typically acrylate esters such as methyl methacrylate or ethyl acrylate. Styrene acrylic dispersion is a universal binder with a low minimum film formation temperature and high elasticity. It is used in the production of flexible stone, primers, putties, and plasters for external and internal use, highly filled construction adhesives, facade thermal insulation systems, concrete modification, and waterproofing membranes.

[0014] Dioctyl adipate (DOA) is a non-toxic, highly effective plasticizer for polyvinyl chloride, cellulose ethers, chlorinated rubber, polyvinyl acetals, polystyrene, acrylic, and other synthetic resins. It is included in the list of safe substances approved for use in contact with food products. DOA plasticizer is a clear, odorless, colorless liquid. It is insoluble in water, soluble in most organic solvents, and miscible with most plasticizers used in PVC processing. Under normal conditions, the product is resistant to hydrolysis.

[0015] Polyvinyl acetate (PVA) is a colorless thermoplastic polymer that is insoluble in water, resistant to UV radiation, oils, and gasoline, and is non-toxic. After drying, PVA forms a strong, transparent, vapor-permeable film that is virtually invisible in finished products. The technical characteristics of the polymer are adjusted by adding various additives. This combination of excellent technological properties makes PVA indispensable in many industries. Polyvinyl acetate dispersion is a product of the polymerization of vinyl acetate in an aqueous medium in the presence of a reaction initiator and a protective colloid (polyvinyl alcohol). In PVA dispersion, the dispersed phase is polyvinyl acetate (a solid), and the dispersion medium is water (a liquid). Externally, the material is a viscous liquid of white or slightly yellowish color with a uniform structure without solid inclusions or lumps. The presence of individual air bubbles is allowed.

[0016] Novopol 007 can be used as an acrylic dispersion. According to the manufacturer's specifications, it is environmentally friendly, moisture-resistant, resistant to ultraviolet rays, and has a working temperature range from +2 to +35°C.

[0017] The composition of the claimed technical solution is obtained by gradually mixing the components in a container under standard conditions (temperature -20-25°C, pressure - 1 atmosphere). Mixing all components at once is strictly prohibited. The composition is prepared in the following stages:

[0018] 1. DOA (dioctyl adipate) is added to the base, which is Novopol 001 styrene acrylic dispersion (styrene acrylic dispersion from other manufacturers can be used), after which the resulting composition is left to stand for at least 10 hours.

[0019] 2. Add the thickener novopol 007 to the settled mixture, after which the resulting mixture is left to settle for at least 5 hours.

[0020] 3. PVA dispersion is added to the mixture. Let it stand for at least 5 hours.

[0021] 4. After applying the composition in one layer and drying for 6 hours at a temperature of 20-25°C, a transparent, adhesively strong and waterproof layer is formed, which maintains its seal during multiple wetting and drying cycles.

[0022] Below are examples of the invention.

[0023] Example 1.

[0024] To prepare 100 liters of working composition we used:

[0025] 61.6L styrene acrylic dispersion;

[0026] 2.2 l dioctyl adipate;

[0027] 2.2L acrylic dispersion;

[0028] 34 l PVA dispersion.

[0029] The resulting mixture was applied with a brush to a plasterboard tray. After drying for 6 hours, the container was filled with water and left for 30 days. No leaks were detected. After the water evaporated and the container was refilled for another 30 days, no defects were detected. The container was then kept dry for 4 months, after which it was refilled with water, which again revealed a complete leak-proof seal.

[0030] Example 2.

[0031] 50 liters of working composition are prepared in the same way:

[0032] 32 L (64 wt%) styrene acrylic dispersion;

[0033] 1 l (2 wt%) dioctyl adipate;

[0034] 1 L (2 wt%) acrylic dispersion (thickener);

[0035] 16 l (32 wt.%) PVA dispersion.

[0036] The prepared mixture is sprayed with an airless sprayer in an even layer onto a concrete block (20 x 20 x 20 cm). After 8 hours of drying at 25°C, the resulting layer is subjected to climatic testing: 20 cycles of 3 hours of complete immersion in water and 3 hours of drying at 50% relative humidity. Adhesion to the substrate was maintained, the layer remained transparent, and there were no cracks or peeling.

[0037] Example 3.

[0038] 70 liters of working composition are prepared in the same way:

[0039] 46.2L (66 wt%) styrene acrylic dispersion;

[0040] 1.26 L (1.8 wt%) dioctyl adipate;

[0041] 1.26 L (1.8 wt%) acrylic dispersion (thickener);

[0042] 21.28 l (30.4 wt%) PVA dispersion.

[0043] The proposed technical solution has the following advantages:

[0044] - transparency after drying, allowing the use of primer under decorative coatings,

[0045] - universal application in wet and dry rooms,

[0046] - economy: cost price is lower than similar products due to optimized proportions.

Claims

A waterproofing primer containing styrene-acrylic dispersion, dioctyl adipate, a water-soluble thickener and a polyvinyl acetate dispersion, characterized in that Novopol 007 acrylic dispersion is used as a water-soluble thickener, with the following ratio of components, wt.%: - styrene-acrylic dispersion - 61.6-66; - dioctyl adipate - 1.8-2.2; - acrylic dispersion - 1.8-2.2; - polyvinyl acetate dispersion - 30.4-34.