CS247978B1 - Impregnating and insulating materials, in particular for the building industry - Google Patents

Abstract

The solution concerns an impregnation and insulation material intended for the construction industry. The purpose of the solution is to reduce the penetration of water and aqueous solutions through concrete surfaces by means of new flexible to tough materials and thus improve the long-term waterproofing of water management structures. This concerns not only the reduction of water leakage from tanks, but also the reduction of contamination and pollution of groundwater. The stated purpose is achieved by using new types of epoxy tough materials prepared by curing a mixture consisting by weight of 60 to 90 parts of epoxy resin, 10 to 40 parts of C^ to alkyl acrylates and aliphatic polyamines or aminoamide resins in an amount of 90 to 140% of theory, based on the content of epoxy and acrylic groups in the mixture, at a temperature of 5 to 40 °C. The reactive composition further contains fillers, pigments, hardening accelerators and additives regulating mechanical and technological properties. The good properties of new materials can be used not only in agricultural construction, but also in other construction fields, such as industrial buildings, water management structures, repair of concrete defects, tanks, etc.

Description

The invention relates to impregnating and insulating materials, in particular for the building industry, suitable for forming protective coatings and layers to prevent water and aqueous solutions from penetrating the cement surfaces of tanks, pools, reservoirs, sewers and the like.

Our country does not have large reserves of water. That is why we must manage it well, protect our drinking water resources. Especially in such areas as the South Moravian Region. Long-term watertightness is required not only for sanitary water structures such as reservoirs, storage tanks, sewage treatment plants and the like, but also for ground tanks, silage pits, swimming pools, digesters, sewage pits and the like.

Hardened concrete can be adversely affected by various chemical influences, either by attacking water, by the action of gases and air, by soil and soil minerals, or by chemicals. The attacking waters attack concrete most often. In addition to the concentration of the aggressive components contained in it, its amount is also important. The attacking waters disrupt the concrete by disrupting and leaching the components of the cement, forming new, less solid compounds, or forming insoluble compounds which increase their volume and expand the concrete by expansion. As attacking water we mean hungry, acid, carbonic, sulphate, chloride waters.

At first there was an effort to produce waterproof cement plasters. However, their quality depends too much on the quality of the workmanship, otherwise it often bursts, becomes permeable and requires expensive repairs. Progress was achieved by machine plastering and the use of colloid mortar. However, the results did not satisfy and even sealants such as calcium and alkaline soap did not solve the problem, since they only sealed the micropores in the binder, which must themselves be dense and impermeable. In most cases, sealants reduce the mechanical strength of both mortars and concretes, so they cannot be used in new concretes and in some environments, admixed concretes break down before concretes without additives.

That is why bituminous insulation systems have been used for many years. They are an integral part of the building structure and consist of various primers, asphalt sealants, hot-applied as well as a series of superimposed reinforcing inserts joined by asphalt coatings and the like. As temperatures fall 8le they become brittle and lose their flexibility to the deformations of the substrate.

Rheological properties, in turn, limit their use to a certain temperature range. Exceeding it is often the cause of many failures. Asphalt resins are more cavelite than tar. In cold weather there is a risk of premature solidification of the nut and thus their poor spreading.

If the temperature of the base masonry is lower than +5 ° C, the masonry must be heated, otherwise the cracks in the coating would be rendered worthless. The frost coating is brittle and slightly damaged. Another disadvantage of resins is that they have a constant plastic flow.

Recently, plastics have been increasingly used in the Czech Republic and abroad. They are, for example, films of polyvinyl chloride. Their disadvantage is the difficult and often imperfect connection (by gluing, hot air and high frequency heating) and then that the water extracts from the plasticizer films, the films harden, crack, lose elasticity and leak. They are therefore only suitable as intermediate insulation.

Joining metal strips is even more difficult. The use of silicones encounters considerable shrinkage. Classical epoxy resins have low ductility and cracking when concrete is deformed,. Polyethylene boards and foils are very chemically resistant, flexible, lightweight, but their bonding is often imperfect. There are also problems with bonding rubber bands, especially in bends and corners. Moreover, they are difficult to handle due to their large weight. Enamel coatings (polystyrene, epoxy) have a limited service life. Sometimes concrete is protected by fluctuation. Overall, the problem of preventing the ingress of water and aqueous solutions in the construction industry is very complicated and the state of the art does not yet know the full solution.

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We have now found that substantially more flexible and resilient, reduced shrinkage and durability impregnating and insulating materials will provide resilient epoxyacrylates prepared by reacting mixtures consisting of 60-90 (preferably 70-80) parts of an average molecular weight of 370 up to 600, 10 to 40 (preferably 20 to 30) parts up to ΰ, θ of alkyl acrylates and aliphatic polysmines or aminoamide resins in an amount of 90 to 140% of theory, based on the epoxy and acrylic group content of the mixture, at 5 to 40 ° C (preferably 15 to 25 ° C).

The properties of the masses obtained according to the invention can be varied by influencing the density, polarity and topology of the structural network of the mass by changing the quality and quantity of the starting components. By changing the types and proportions of fillers, it is possible to influence mechanical and electric properties (strength, abrasion, surface resistance, etc.) and workability (viscosity, thixotropy). Fillability can also be influenced by the amount of hardener.

The epoxy resins used are prepared by known methods by condensation of epichlorohydrin with bisphenols in an alkaline medium. The amine and polyaminoamide curing agents used according to the invention have amine numbers of 150 to 1800 mg KOH / g and cause curing of the liquid compositions of the invention at temperatures of 0 to 60 ° C, at an amount corresponding to 90 to 140% of the theory relative to the reactive group content.

In curing, substances that retard or accelerate the chemical reactions of the compounds in a mixture such as phenolic compounds, water, polyols, thiols, ketones, cyclic ethers and the like can be used. Sometimes it is appropriate to use substances affecting the flow, surface tension and the like.

Common fillers such as graphite, sand, talc, chalk, gypsum, glass flour, diatomaceous earth, ground fireclay, fly ash, cement, corundum and garnet waste, amorphous silica, silica gel, alumina, metal dust, asbestos, powder polyvinyl chloride and other polymers and copolymers, pigments such as zinc oxide and the like.

The materials according to the invention have a resilient and tough character, which is characterized by a ductility of 10 to 50% at a tensile strength of 30 to 70 KPa and a phase toughness of 40 to 90 kJ / m 2. It features excellent adhesion, wear resistance, weathering and temperature and water and oil tightness. These good properties can be used especially in agricultural construction, as well as in repairs of concrete failures, concrete tanks and the like.

The protective coatings and layers of the compositions according to the invention are prepared by coating, rolling, spreading, ballasting, spraying, laminating and the like. Preferably on a penetrated surface. Multiple layers of the same and different quality can be combined. It is important to thoroughly mix all components and apply so that there are as few air bubbles as possible in the protective coatings and layers. Care must be taken not to allow moisture or dirt to enter between the layers.

This could impair the adhesion of one layer to the other. Cement surfaces must be dry, stiff, slightly rough, free of cement milk, dust and loose particles, free of oil and grease or other impurities that could impair adhesion. If desired, the surface may be sandblasted, flamed, abraded, and the like. Pressure blasting is sometimes useful.

Example 1

Reactive mixture consisting of 70 wt. parts of epoxy resin having an average molecular weight of 570, 30 wt. parts of 2-ethylhexyl acrylate and 8.59 wt. parts of diethylenetriamine, corresponding to 100% of theory, will provide a curing mass having a tensile strength of 47 MPa, an elongation at break of 14% and an impact strength of 52 kJ / m @ 2 for curing. 11.17 wt. parts of diethylenetriamine (130% of theory), then the cured mass has a tensile strength of 48 MPa,

% and impact strength 88 kJ / m.

Example 2

Reactive mixture consisting of 80 parts by weight of epoxy resin having an average molecular weight of 440.5% by weight. 15 parts by weight of 2-ethylhexyacrylate and 14.4 parts by weight of n-butyl acrylate;

parts of teraethylenepentamine, which corresponds to 110% of theory, will give a tough and resilient mass having a tensile strength of 65 MPa and a ductility of 1% and an impact strength kJ / m ² after curing.

Example 3

Reactive mixture consisting of 70 wt. parts of epoxy resin having an average molecular weight of 575, 30 wt. parts by weight of 2-ethylhexyl acrylate, 27 wt. parts by weight of copolymers of ethylene and vinyl acetate; parts of triethylenetetramine, after curing, provides a tough and highly adhesive mass having a tensile strength of 57 MPa, an elongation of 9% and an impact strength * kJ / m ² .

Claims (1)

SUBJECT OF THE INVENTION Impregnating and insulating materials, in particular for the building industry, suitable for the preparation of protective coatings and water-barrier layers and aqueous solutions obtainable by curing a mixture consisting of 60 to 90, preferably 70 to 80, parts by weight of epoxide resin with an average molecular weight of 370 to 600, 10 to 40, preferably 20 to 30 parts by weight _of alkyl acrylates and aliphatic polyamines or aminoamide resins in an amount of 90 to 140%, based on the content of epoxy and ecrylate groups in the mixture, at a temperature of 5 to 40 ° C, preferably Mp 5-25 ° C.