CS250322B1 - Aminopolymer mastic - Google Patents

Description

BACKGROUND OF THE INVENTION The present invention relates to an aminopolymer sealant for filling cavities, joints, re-sealing surfaces, and for resiliently joining elements. It is formulated on the basis of aminoesters of polymeric acids in the form of aqueous dispersions of synthetic polymers with fillers, plasticizers, reinforcing fillers and corrective additives.

Until now, sealants based on synthetic or natural macromolecular substances modified with plasticizers and fillers have been used. According to Pat. US 3,887,442 uses a combination of polypropylene and asphalt, according to Pat. Me p. 6806—630–68, 6927–002–69 and, 7031–197–70 a partially hydrolyzed ethylene vinyl acetate copolymer is used, according to AO CSSR 154 136 a mixture of rubber, polyethylene, plasticizers, etc. dry substrate. Thermoplastic-based sealants are often used as hot-melt adhesives (U.S. Pat. No. 3,849,353, 3,850,858, 3,864,301, etc.). These require heat treatment and heating of the bonded surfaces before bonding. Cementitious compounds based on reactive synthetic resins (EP, UP, PUR, etc.) are two-component, containing organic solvents and solvents and require special modifications of the cemented joints as well as a demanding processing procedure.

Waterborne based cements have so far been used to a limited extent for the high volume changes resulting from the evaporation of water, the content of which usually exceeds 20% by weight. of the total cement mass. In the case of thicker layers, these bonding materials cause cracks and deformation due to water loss. Therefore, increased attention is paid to the preparation of water-based binders with a minimum water content. These aqueous dispersions are difficult to prepare because as the content of dispersed particles in the emulsion system increases, coagulate is formed and electrochemical stability is impaired. However, it has been found that aqueous emulsions of synthetic polymers containing an unsaturated acid in the molecule form ammonium salts with aqueous ammonia, and the resulting dispersion has completely different properties to the original as described in U.S. Pat. US 3,037,952. Increases viscosity and consistency of idispersion, changes rheological properties, substantially decreases minimum film-forming temperature, increases resistance to low and elevated temperatures, improves mechanical stability, and the like. The film formed from such dispersion has substantially greater flexibility, softness , lower volume changes and thermal expansion, higher resistance to elevated temperatures, higher diffusion resistance, etc. Film stickiness is also often affected. The ammonium salts of the polymer dispersions are formed during neutralization with an aqueous ammonia solution, thereby increasing the water content of the binder. Therefore, dispersions treated in this way are used only for special-purpose bonding materials in the paper industry.

These drawbacks are overcome by the inventive aminopolymer dispersion cement, the binder of which is the amine esters of the aqueous dispersion of the synthetic polymer or copolymer. The amine esters are formed by neutralizing an aqueous dispersion of a synthetic polymer containing unsaturated organic acid in the polymer chain in an amount of 3 to 35% by weight. based on polymer weight alkanolamines or alkylamines containing from 3 to 12 carbon atoms and boiling point within the range from 50 to 230 ° C ³ proved to be suitable amines are secondary and tertiary alkanolamines, namely diethanolamine, trietanolaním, diethylaminoethanol, N-methyldiethanolamine and dicyclohexylamine, diethylamine and triethylamine. Said amines are used in the anhydrous state and the formation of aminopolymers increases the dry matter of the binder. The modified amine compound dispersions are toomogenized with phthalate type plasticizers, with fillers having a grain size of up to 0.5 mm, preferably up to 0.2 mm, colloidal silicon dioxide and / or chalk, optionally with hydrophobizing additives, fibrous reinforcing fillers and pigments. The complete homogenization of all the components results in a thixotropic dispersion putty aminopolymer compound with a low water content and therefore a low degree of shrinkage. The sealant cures in the air and forms an impermeable elastic film on the sealant surface, which prevents further evaporation of water. The sealant retains elasticity, ductility and exhibits good plastic properties. The aminopolymer sealant has good adhesion to both dry and damp substrates and forms a continuous, impermeable layer with high adhesion properties. It is suitable for application by spatula, pressure airless spraying and for extrusion from manual and pneumatic sealing guns.

EXAMPLE 1 32 parts by weight of an aqueous dispersion of styrene-2-ethylhexyl acrylate-acrylic acid having a dry weight of 50% by weight are gradually added to the mixer in parts by weight. and containing 5% acrylic acid by polymer, 2.2 parts of diethylaminoethanol, 9 parts of di-n-butyl phthalate, 3 parts of calcium stearate, 12.8 parts of colloidal silica, 40 parts of finely ground limestone with a grain size of up to 0.2 mm and 1 part technical fibrous cellulose. After perfect homogenization, a paste-like, thixotropic adhesive is produced, which does not run off, even in 10 cm thick layers, and is easily applied with trowels or sealing guns. The sealant is characterized by stability in the temperature range of -30 to - (-90 ° C), alkali resistance, weather resistance and very good adhesion to porous silicate materials, which is higher than the cohesion of the sealant.

Example 2

25 parts of an aqueous dispersion of ethyl acrylate-1-butylacrylyl-methacrylic acid-crotonic acid with a dry matter content of 55% by weight are perfectly homogenized in a mixer. and a 1: 1 content of methacrylic acid and crotonic acid of 20% by weight of polymer, 6 parts by weight of a mixture of diethanolamine and triethylamine in wt. 1: 1 ratio, 8 parts of di-octyl phthalate, 9 parts of float chalk, 50 parts of finely ground limestone with a grain size of up to 0.1 mm, 1 part of technical fibrous cellulose and 1 part of pigment. After homogenization, a thixotropic sealant is formed with good adhesion to dry and wet substrates. It forms on the surface of the sealant within 10 min. at 20 ° C, a non-sticky blank. When applied in thicker layers - usually above 2 c.m - the sealant with gradual drying creates a concave surface. Upon reaction, the sealant forms a flexible joint and exhibits plastic properties.

Claims (4)

CLAIMS 1. Amino-polymeric sealant for filling cavities, joints, re-sealing surfaces and for elastically joining elements, characterized in that it consists of a homogenized mixture of 20 to 55 parts of an aqueous synthetic polymer dispersion having a dry weight of 40 to 60% by weight. and containing from 4 to 35% by weight of an unsaturated organic acid comonomer. based on the polymer content, 1.5 to 15 parts of alkanolamines and / or alkylamines containing 3 to 12 carbon atoms and boiling in the range of 50 to 200 ° C, 5 to 20 parts of phthalate type plasticizers, 6 to 20 parts of thixotropic fillers, with preferably from colloidal silica or float chalk, 30 to 60 parts of finely ground limestone with a grain size of up to 0.5 mm, preferably below 0.2 millimeters, and 0.4 to 2.0 parts of the technical cells of the bed fibers, all in mass parts. 2. A compound according to claim 1, wherein the comonomer of the unsaturated organic acid is acrylic acid, methacrylic acid, crotonic acid or itaconic acid, or mixtures thereof. 3. A compound according to claim 1, wherein the alkanolamines are diethanolamine, triethanolamine, diethylaminoethanol, N-methyl-diethanolamines, and n and the alkylamines are diethylamine, triethylamine, dicyclohexylamine, or combinations thereof. 4. Amino-polymeric sealant according to claims 1 to 3, characterized in that it comprises 1 to 5 parts by weight. % of hydrophilic additives, preferably fatty acids or salts thereof, and 0.5 to 3.0 parts of pigments per 100 wt. parts of the sealing compound.