CS254558B1 - An aqueous composition for bonding - Google Patents

Abstract

For bonding two parts of one or more materials, at least one of which has an absorbent character, such as wood, plaster, concrete, gas silicate, chipboard and the like, an aqueous composition is proposed consisting of 0.4 to 6 parts by weight of starch or its derivatives with an ether bond, 2 to 15 parts by weight of a water-dilutable binder, for example an aqueous dispersion of a thermoplastic polymer or copolymer, a colloidal solution of silicon dioxide, an aqueous solution of alkali silicate and water, or other additional components such as hydrophobics, wetting agents, fungicides, inert fillers and protective colloids. Starch is supplied to the composition in the form of an aqueous solution or in a dispersion form (starch grease) or is used in a cold, rapidly soluble form. This composition can be used in construction, furniture making, cardboard production and the like.

Description

The invention relates to the composition of an aqueous composition for bonding various materials, with the exception of polyolefins and metals, to absorbent substrates, for example wood, plaster, concrete, gas silicate, chipboard agglomerates and the like.

For bonding various materials to absorbent substrates such as wood, plaster, concrete, gas silicate, wood fiber or chipboard agglomerates, adhesives based on aqueous solutions of glue, casein, cellulose derivatives, starch, etc. or aqueous polymer dispersions, etc. are used.

However, these materials have a number of disadvantages, especially when applied to more absorbent substrates, such as soft wood, gas silicate, etc., especially in terms of the length of workability, rapid absorption of mixing water into the substrate, easy re-dissolution of the adhesive in the joint by accidental water, etc. Waterproof adhesives are usually formulated as solutions of various polymers (rubbers, polystyrene, etc.) in an organic solvent or they are two- or multi-component, chemically curable systems (for example, epoxy or polyester type, etc.). These systems are demanding on raw materials and the use of organic solvents requires compliance with safety measures.

The above disadvantages are completely eliminated or at least significantly reduced by a composite adhesive system, the essence of which is the combination of a starch composite in the form of a solution or grease of 0.4 to 6 parts by weight of starch or its derivatives with an ether bond, for example starch carboxymethyl ether, (or their combination) further 2 to 15 parts by weight of an additional binder diluted with water, for example an aqueous dispersion of a thermoplastic polymer from the group of homopolymers polyvinyl acetate, polymethyl methacrylate, polybutyl methacrylate, or from a set of copolymers formed by copolymerization of components from the following monomers: vinyl acetate - butyl acrylate, vinyl acetate - 2,6 ethylhexyl acrylate, styrene - 2,6 ethylhexyl acrylate, styrene - butyl acrylate, methyl methacrylate - butyl acrylate, methyl methacrylate - 2,6-ethylhexyl acrylate, butyl methacrylate - butyl acrylate with a dry matter of 25 to 70% by weight, a colloidal solution of oxide of silica with a dry content of 15 to 50% by weight, an aqueous solution of alkali silicate with a dry content of 15 to 50% by weight.

The starch is supplied to the composition in the form of an aqueous solution or in a dispersion form, that is, in the form of a starch grease, or is used in a cold, rapidly soluble form; the remainder up to 100 parts by weight is mixing water. The composition may contain additional additives such as 0.01 to 2 parts by weight of a hydrophobic agent, for example of the alkyl silanolate type,

0.01 to 1 part by weight of a wetting agent based on lauryl sulfates or alkaline polyphosphates,

0.001 to 0.2 parts by weight of fungicides, for example organotin salts, and optionally 4 to 25 parts by weight of inert fillers, for example kaolin, chalk, micro-ground limestone and rheologically active fillers such as ground halloysite, bentonite, amorphous silica, silica fume and the like, and 0.05 to 0.5 parts by weight of protective colloids, for example cellulose derivatives.

Adhesives formed in this way are highly viscous, with good workability in the order of tens of minutes, and their reversible disruption with water and common organic solvents is possible, but time-consuming, which means that accidental spillage with these liquids does not cause significant disruption.

The advantages of using composite adhesives that can be formulated in this way are better illustrated by the following examples:

Example No. 1

By heating to a temperature of approximately 67 °C with constant stirring, the following starch-based ointment composition was created with the following composition:

potato starch corn starch carboxymethylcellulose water % mass 2 % mass 1 % mass % mass

After cooling, this ointment composition was mixed with a polymer dispersion of styrene-acrylate copolymer with a dry matter content of 51% by mass and other modifying components in the following ratio:

tallow starch composition styrene acrylate dispersion water glass 38°Bé

10% aqueous solution of fungicicd organotin type hexametaphosphate water

11.1 parts by mass 11.1 parts by mass 2.2 parts by mass sodium 1.1 parts by mass 0.1 parts by mass 74.4 parts by mass

The resulting composition was used as a bookbinding glue.

Example No. 2

The following water-based composition was created:

cold water-soluble potato starch 1.5 material parts aqueous dispersion of vinyl acetate acrylate copolymer (dry matter 52%) 10 material parts colloidal silicon dioxide solution 10 . material parts (dry matter 30%) alkylsilanolate-type hydrophobic 1 material part lauryl sulfate type wetting agent 1 material part organotin fungicide 0.1 material parts water 76.9 material parts

The composition was used for gluing washable PVC wallpapers with a paper backing to concrete beams of a silicate residential core for the bathroom area.

Example No. 3

The following water-soluble carboxymethyl starch colloidal solution of silica water glass 38°Bé kaolin floated lauryl sulfonate-type wetting agent organotin fungicide water composition was created:

mass part 12 mass parts mass parts 7 mass parts 1 mass part 0.1 mass parts

74.9 parts by mass

The resulting composition was used for auxiliary bonding of joints of a prefabricated wooden structure of a light agricultural building intended for storing fodder.

The material according to the above invention is useful for bonding joints of two or the same material, at least one of which is absorbent, in bookbinding, construction, cardboard production, furniture making and the like.

Claims (2)

An aqueous composition for gluing two parts of one or more materials, at least one of which is absorbent, formulated on the basis of starch or its derivatives and an additional binder of a more hydrophobic nature, characterized in that it contains per 100 parts by weight of the total weight of the mixture 0, 4 to 6.0 parts by weight of starch or an ether-linked derivative thereof, for example, carboxymethyl starch, or a combination thereof 2 to 15 parts by weight of a water-borne supplementary binder, for example an aqueous dispersion of thermo254558 plastic polymer or copolymers selected from the group of polyvinyl acetate homopolymers , polymethyl methacrylate, polybutyl methacrylate, or from the group of copolymers consisting of vinyl acetate - butyl acrylate, vinyl acetate - 2,6-ethylhexyl acrylate, styrene - butyl acrylate, methyl methacrylate - butyl acrylate, methyl methacrylate - 2,6-ethylhexylacrylate - butylacrylate 70% o, 15 to 50% by weight of aqueous colloidal silica, 15 to 50% by weight of aqueous alkali silicate, wherein the starch is introduced into the composition in the form of an aqueous solution or in the form of a dispersion, e.g. it is used in the form of cold, fast-dissolving or other additives and the rest up to 100 parts by weight is mixing water. 2. An aqueous composition according to claim 1, characterized in that it contains from 0.01 to 2 parts by weight of a hydrophobic agent, for example of the alkylsilanolate type, from 0.01 to 1 part by weight of a surfactant based on lauryl sulphates or lauryl sulphonates or alkaline polyphosphonates. parts by weight of fungicides, for example organotin salts, and optionally 4 to 25 parts by weight of inert fillers, for example kaolin, chalk, micronized limestone and theologically active fillers such as ground haloyzite, bentonite, amorphous silica, silica fume and the like, and 0.05 to 0, 5 parts by weight of protective colloids, for example cellulose derivatives.