CS249231B1 - Mineral-fiber heat-insulating board with cellulosic binder and method of its production - Google Patents

Abstract

The solution relates to a mineral fiber thermal insulation board and a method of its production. The mineral fiber thermal insulation board consists of mineral fibers, fillers such as halloysite, kaolin, bentonite, perlite, hydrophobic emulsion, aluminum sulfate, flocculating agent based on polyacrylamides and water-soluble cellulose derivatives. The mineral fiber boards according to the solution can be used as an insulating material for thermal insulation of buildings.

Description

249231

BACKGROUND OF THE INVENTION The present invention relates to a mineral fiber-reinforced cellulose wadding with a cellulosic bonding process.

Mineral fiber and ceramic filler thermal insulating docks are currently made by papermaking technology, with the binder forming a native but not bleached shell. At present, the composition consists of components: mineral fiber, ceramic filler (halloyzite, kaolin, bentonite), paraffin emulsion, aluminum sulphate and flocculating agent. From these components, it prepares an aqueous suspension having a content of from 1 to 3% by weight, which is drained from the molding machine and the wet thatch is dried. Because of the low solids content of the suspension, this method of production requires a binder of specific properties. Such a technologically preferred binder is starch. In the first phase of the process, the solid constituents of the composition are captured and, in the case of subsequent heat treatment, a film is formed on the ceramic fiber glass as a binder. It is not disadvantageous in that starch is an important food product, a raw material, has a low microbiological resistance and a relatively high price for high-volume production, such as that of the thermally insulated boards.

These drawbacks are eliminated in the mineral-fiber insulating dock with the cellulosic bonding agent according to the invention, which is based on mineral-fiber-reinforced mineral fiber, ceramic fillers and additives, characterized in that it consists of 60 to 90% by weight. % mineral fibers, 1 to 15 wt. % of ceramic fillers such as halloyzite, kaolin, bentonite, perlite, from 0.6 to 1.2 wt. % hydrophobic emulsion, from 0.5 to 2 wt. sulphonate, from 0.005 to 0.05% of a polyacrylamide-based flocculant and from 3 to 10% by weight of a water-soluble cellulose derivative, preferably carboxymethylcellulose or hydroxymethylcellulose. The binder-soluble cellulose derivative is introduced into the system of suspension in powder form in the air laundry prior to dewatering and the suspension is drained prior to dissolution of the cellulose derivative.

SUMMARY OF THE INVENTION The present invention is based on the application of a binder of water-soluble cellulose derivatives such that their spreading occurs to a major extent only in the product, in the wet plate. The dissolution of the cellulose derivative takes place in a wet plate during its transport to the dryer and, in particular, in the first part of the dryer, as the material does not dry but only heats as a result of the steam supply.

The material emerging from the forming machine contains about 50 wt. water. When the cellulose derivative is dissolved in this amount of water, a relatively concentrated colloidal solution is formed; According to the content of cellulose derivative in the dry state, the concentration of 3 to 10% by weight is preferred. In this state, the binder yields a semi-solid gel consistency which causes good constancy of the components of the composite. The material has some strength in the wet state, so there is no problem with transport to the dryer.

The cellulose derivatives are introduced into the slurry, which contains all the components, on the molding machine in the sus-pension inflow into the machine. Under these conditions, the cellulose derivatives are only up to 30 seconds in short contact with the pre-water. During this time they will not dissolve in the system. After suspension, the cellulose derivative particles are drained off in a wet plate. In a further wet dock process, a binder of material is dispersed therein and thus formed. If the link were introduced into the system earlier, it would completely dissolve in the excess of water, and the drainage would enter into the subshells, thereby failing to function.

The main advantage of the present invention is that it uses a bond for the production of thermal insulation boards which is approximately half the price of starch and is not a food raw material.

The technological process of making insulating bottles is simple. The difference with the existing technology is merely that the binder, the cellulose derivatives, is introduced into the system by the molding machine. The cellulose derivatives in powder form are introduced into the air-suspension suspension by a pump-type device. In doing so, the binder particles individually enter the slurry, making it impossible to form aggregates, agglomerates, dispersing the problems.

In addition to bringing the binder into the system, the process of preparing the insulating plates is a conventional technique: an aqueous suspension is prepared from the ingredients, which contains 1-3% by weight. solids.

The suspension may be prepared by the following methods: (a) the individual components are successively introduced into the suspension in the order of the fiber, the ceramic filler, the aluminum sulphate (pH-4,5), the flocculating agent and the cellulose derivatives are separately prepared to form two suspensions, which together are blends [(fibers), (clays and hydrophobic emulsion)], then aluminum sulfate, flocculating agent, and cellulose derivatives are added.

The suspension is filtered under suction, compressed by compression and dried at 120-150 ° C. In the first part of the dryer, water vapor is blown into it to completely dissolve the cellulose derivative in the wet plate.

Claims (2)

249231 Examples What is claimed is: 1. A mineral-fiber heat-insulating plate with a cellulosic binder composed of mineral fibers, ceramic fillers and additives, characterized in that it consists of 60 to 90% by weight. % of mineral fibers, 1 to 15 wt. ceramic fillers such as hyalloyite, kaolin, bentonite, perlite, from 0.6 to 1.2 percent by weight; % hydrophobic paraffin emulsion from 0.5 to 2 wt. % aluminum sulfate, from 0.005 to 0.05 wt. % of a flocculant based on polyacrylamides and from 3 to 10 wt. water-soluble cellulose derivatives. VYNALEZU 1. The composition of the mineral-fiber heat-insulating cushion prepared according to the invention (expressed in% by weight on dry weight of thatch): mineral fiber 79.7 kaolin 7.0 bentonite 3.0 paraffin emulsion 0.8 'aluminum sulfate 1.5 flocculating agent 0.007 Carboxymethylcellulose 8.0 An aqueous suspension of 2% by weight is prepared from the above ingredients, with the increment and order of dosing of the ingredients as above. Carboxymethylcellulose is suspended in suspension on an air-jet injector. The slurry is dewatered on the mold and hardened by pressing. Dry at 130 ° C. In the first part of the dryer, the insulating shells are heated with water vapor to achieve the desired properties of the binder. Properties of mineral fiber insulation: 340 kg. m-3 bending tensile strength 2.8 MPa 2. The composition of the mineral fiber fibrous insulation (weight% in dry matter) prepared according to the invention: mineral fiber 89.2 kaolin 1.0 bentonite 0.5 paraffin emulsion 0.8 aluminum sulfate 1.5 flocculating agent 0.007 carboxymethyl cellulose 7.0 2 wt. an aqueous suspension in the same manner as in Example 1. Carboxymethylcellulose is suspended in suspension on an air-jet injector. The suspension is drained on a forming machine and molded by compression. The wet thatch is heated in a water bath in the first part of the oven and then dried at 140 ° C. Properties of mineral-fiber heat-insulating thatch: 240 kg. m ~ 3 bending tensile strength of 2.2 MPa 3. The composition of the mineral fibrous heat-insulating that is prepared according to the invention (expressed in% by weight on the dry weight of thatch): mineral fiber 91.2 kaolin 1.0 bentonite 0.5 paraffin emulsion 0.8 aluminum sulfate 1.5 flocculating agent 0.007 hydroxymethylcellulose 5 From these components, a 2% w / w suspension is prepared in the same manner as in Example 1. Hydroxymethylcellulose is introduced into the slurry on an air-injector molding machine. The slurry is dewatered by a shaping machine and molded by compression. Wet soils are heated with water vapor in the first portion of the dryer and then the temperature is 130 ° C. Properties of mineral-fiber heat-insulating thatch: 220 kg. m ~ 3 bending tensile strength 1.9 MPa P R E D Μ E T 2. A process for the production of a mineral-fiber teo-thermal dock according to claim 1, comprising the preparation of suspensions, dewatering, refining and drying, characterized in that the binder, which is a water-soluble cellulose derivative, is introduced into the suspension system by powder in the stream. the air before pretreatment and then the suspension is drained before the cellulose derivative is dissolved.