SU1702871A3 - Binder - Google Patents

Abstract

Use: in the manufacture of building ceramics. The essence of the invention: the host contains in the solid phase grains on silicon oxide with the following distribution of grains in fractions, wt.%: 0.01-0.02 µm 0.1-1.2; 0.02-0.03 micron 0.10, 8; 0.03-0.04 micron 0.1-0.6; 0.04-0.05 micron 0.1-0.7; 0.05-0.06 μm 0.1-0.7; 0.06-0.08 micron 0.2-1; 0.08-0.1 μm 0.3-1; 0.1-1 micron 8-19; 1-10 microns 31-43; 10-20 microns 19-21; 20-40 microns 11-28; 40-100 microns 2-11. At the same time, it contains 1-3 May. shares of calcium oxide at 100 May. share in the slider in the solid phase. The slurry contains silicon oxide grains at the next grain distribution by fraction, m wt.%: 0.01-0.02 μm 0.5; 0.02-0.03 micron 0.5; 0.03-0.04 μm 0.4; 0.04-0.05 μm 0.2; 0.05-0.06 μm 0.5; 0.06-0.08 μm 0.6; 0.08-1 μm 0.5; 0.1-1 μm 17; 1-10 microns 42; 10-20 microns 20; 20-40 microns 15; 40–100 µm 3. 3. The freeze resistance of 19–42 cycles, water absorption 8.5–9.6%, compressive strength 96–118 MPa, 2 hp f-ly, 2 tabl, fe

Description

The invention relates to building materials, in particular, to ceramics, and can be used in the manufacture of products from building ceramics on the basis of a crush-mesenter containing grit.

Silica-containing materials for the manufacture of silica refractories are known (U.S. Patent Mg 24,46975, CL 106-69, Publication August 10, 488). The composition of the binder includes silica (silica) in the following proportions in fractions,%: coarse grains of 9.4-2.4 mm in size 13-30; grains of medium grinding size of 1.17-0.15 mm and fine grain size of less than 0.1 mm 24-31.

However, this composition does not provide sufficient strength properties of products.

after their usual drying at 100-150 ° С. To achieve the physicomechanical properties required in the construction of products, their high-temperature firing at 1400-1450 ° C is necessary. This is an energy-intensive and lengthy process.

A well-known thixotropic composition used in the production of building elements with satisfactory physicomechanical properties (US Patent No. 3,307,612, Cl. 106-69, published on 09/21/65). The composition includes a set of grains of amorphous silicon dioxide of the following fractions,%: 0.80-0.38 mm 37.5; 0.35-0.15 mm 37.5; less than 0.08 mm. 25. Amorphous silica is produced by electrofusion of the feedstock at 1700-1750 ° C. Dry fused silica blend

ABOUT

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shutter with colloidal silica solution which is a binder.

The disadvantage of this composition is that the ingredients used are expensive and scarce synthetic raw materials - fused silica and a solution of colloidal silica. In addition, sufficient mechanical strength of the products is achieved only after firing at 980 ° C, which further increases the cost of the construction element.

It is known that an earth-containing grounding cream (slip) containing water and silicon dioxide dispersed in it, having a purity of at least 99.8% (Application No. 63-139045 by Crony, С 04 В 35/14, published 10 , 06.88), the slip is characterized by the following integral weight distribution of grains of the solid phase of silicon dioxide,%: grains of size 0.006-0.012 mm (or 6-12 µm) BOCO-0.04 mm (respectively 30-40 µm) 80; to 0,001 mm (1 micron) 10-20. ., ... ....

This composition significantly improves dispersibility, uniformity, fluidity, thixotropy, which allows it to be used for forming under pressure,. . . ::.

The disadvantage of this composition is vl -1. As in the previous version, the use of expensive synthetic silica raw materials with a high degree of purity. In addition, to ensure high mechanical strength of the products molded from such a slurry, high-temperature calcination is required or, as proposed in the application, you need to add a special binder component. - ... ... - ..... The closest to the proposed is silica containing

(ed. №771052, cl. С 04 В 15/06, published 15.01.80) for building products, having the following distribution of grains

by fraction, wt.%: 5-20 microns 20-40; 2050µm 12-30; 50-100 microns 1-25, the rest is grains of size 0, microns. . ;

The disadvantage of this silica containing agent is low water and frost resistance. In addition, to obtain building products with sufficient mechanical strength on its basis, it is necessary to use expensive synthetic raw materials - quartz glass, and energy-intensive autoclave, the treatment is carried out at a pressure of 5-25 atm for 2-20 hours.

The purpose of the invention is to increase water and frost resistance while maintaining high mechanical strength.

This goal is achieved by the fact that, in the solid phase, silicon oxide of a continuous fractional composition with a grain size of 0.1–100 µm contains, additionally, grains of silicon oxide with a size of 0.01–0.1 µm with the following grain distribution fraction m, wt.%: 0.01-0.02 micron 0.1-1.2 0.02-0.03 micron 0.1-0.8 0.03-0.04 micron 0.1-0, 6 0.04-0.05 µm 0.1-0.7 f 0.05-0.06 µm 0.1-0.7 0.06-0.08 µm 0.2-1.0 0.08 -0.1 micron 0.3-1.0 0.1-1 micron 8.0-19.0 1-10 micron 31.0-43.0. 10-20 microns 19.0-21.0 20-40 microns. 11.0-28.0 40-100 µm 2.0-11.0 These characteristics of the binder increase further with the introduction of calcium oxide into the composition from 1 to 3 wt.h. per 100 wt.h.

In the proposed composition, the silica, 0.1-100 µm in size, of the susceptible grain performs the function of an active micron-filler, and the particle size distribution as a whole provides the maximum density of the grain packing. The latter determines one of the main criteria that determine the following properties in a bosom; reduction of water demand during water filling, reduction of chabritz segregation, elimination of cracking during drying, obtaining a practically non-shrinking mass.

Particles ranging in size from 0.1 to 0.01 µm are colloidal and, when they are closed with water, form a colloidal solution — a sol with good binding properties; stv.ami,; The high strength properties of the proposed emulsifier. At relatively low concentrations of colloidal particles (1-6 wt.%) Are explained by the following factors:

the homogeneity of the material composition of the microfiller grains (0.1-100 μm) and the colloidal fraction (0.01-0.1 μm); practical continuity of a number of sizes of grains in the composition in jigging, starting from maximum (100 microns) and ending with fine particles (0.01 microns), ensuring accurate placement of colloidal particles in the intergranular space of larger grains in the tinder;

the optimum thickness of the adhesive joint formed from colloidal particles during drying;

the formation of a stronger adhesive joint with an equal concentration of colloidal particles having a continuous fractional composition with a denser packing.

The proposed granulometric composition of the substance contributes to the formation of specific spherical pores. This achieves the effect of a significant increase in water and frost resistance.

The second main criterion determining the aggregate of the optimal properties of the proposed thrasher is the achievement of the optimum rheological characteristics of the casting system, which is formed after the shut-in of the thawing water.

The presence of calcium oxide in the composition as an additive in an amount. 1-3 ma.ch. per 100 wt.h. a treadmill makes it possible to increase the water resistance and strength properties of a material. This is due to the topochemical modification of calcium to the surface of the silica colloidal particles with the formation of phases similar in composition to calcium hydrosilicate. Such modification increases the strength of the adhesive contact between the grains of the suspending agent, which are better resisted by the selective action of water.

P (p and mep, Sustainable get in a known manner (for example, by the author. St. Ns 1055081, class. C 04 B 34/14, published. 01/23/88} by wet grinding of quartz sand in a ball mill with ceramic grinding bodies at a moisture content of 13.0%. The grinding is carried out with three times loading of quartz sand. The readiness criteria are the density of the suspension obtained (2.10-2.24 g / cm3) and its dispersity. The duration of grinding is 15 to 42 n.

In tab. 1 shows the compositions 1-4 proposed in the ghost. .

In tab. 2 shows the properties of the proposed residents (compositions f-4) and the known agent (auth. St. № 771052).

The test samples proposed in the gamblers contained 1-2 May, shares in the ghost. The properties of the samples offered in the living were determined after hardening of the pre-dried castings in a solution of liquid glass with a density of 1.08 g / cm3 for 12 hours and subsequent drying at 110-120 ° C.

The low content of highly dispersed silicon oxide grains in the composition of the carrier (in the range of 0.01–10 µm) leads to unacceptably small values of the strength properties: asj Yu MPa; (7 of 5 MPa.

Composition 1 corresponds to the minimum acceptable strength indicators of water and frost resistance.

An increase in the content of highly dispersed silicon oxide grains in the composition in the substrate in the range of 0.01–10 µm while reducing the grain content of 40–100 µm, which is observed in compositions 2 and 3, leads to an improvement in all properties. Moreover, as can be seen from the table. 2, the best properties in comparison with the known composition and with the compositions of Others

5 samples shows composition 3. It is optimal, since a further increase in the content of silicon oxide grains in the range of 0.01–10 µm and a decrease in their content in the range of 40–100 µm already leads to deterioration of properties.

Composition 4 is the upper limit in fractions. Water and frost resistance and strength properties of this composition are below the optimal variant (composition

5 3). A further increase in the composition of highly dispersed particles, especially less than 1 μm, is a uniquely increasing number of contacts between particles per unit volume.

0 Increasing the likelihood of particles fixing in the position of the near potential minimum leads to a significant rheological structure formation in the system (tixotropy is enhanced). Is strong

5 thixotropy impairs the fluidity in the slurry of the solution, therefore an additional amount of mixing water is required. The latter, in turn, causes a sharp increase in porosity, increases the coupling stresses and leads to a decrease in mechanical strength; frost resistance and water resistance. Preferred is a grain content that corresponds to a Newtonian diffuser or a flow with a significant overlap of thixotropic v dilatant flow types.

The optimal properties of the proposed formulation are achieved with a content of 1 May. calcium oxide fraction

Q May 100 share in the tenant. With an increase in calcium oxide content up to 3 May. a fraction of the strength decreases, and with the introduction of more than 3 May. the proportion of calcium oxide there is a sharp decrease in surface charge

e particles, and the process is heterococci. agulations. The suspension loses its mobility, acquires a pronounced thixotropic nature of the flow, increases porosity, decreases water and frost resistance and strength.

The proposed composition provides a possibility to manufacture cheap construction products on its basis, significantly increasing guarantees for the optimality of their physicomechanical properties. Moreover, to achieve these properties, energy-intensive firing and autoclaving processes are not required, which shortens the manufacturing time of products and thereby increases productivity and reduces the cost of finished products.

Claims (3)

1. Containing, containing in the solid phase silicon oxide of a continuous fractional composition with a grain size from 0.1 to 100 µm, characterized in that, in order to increase water and frost resistance while maintaining high mechanical strength, it additionally contains silicon oxide grains from 0.01 to 0.1 µm with the following distribution of grains by fraction, wt.%: 0.01-0.02 μm 0.1-1.2 0.02-0.03 μm 0.1-0.8 0.03-0.04 μm 0.1-0.6 0.04-0, 05 microns 0.1-0.7 0.05-0.06 microns 0.06-0.08 microns 0.03-0.1 microns 0.1-1.0 microns 1-10 microns 10-20 microns 20-40 microns. 40-100 microns 0.1-0.7 i 0.2-1.0 0.3-1.0 8.0-19.0 31.0-43.0 19.0-2 liO 11.0-28.0 2.0 -11.0. 2. In a pop. 1, that is, in that it contains from 1 to 3 May. calcium oxides by 100 may. share in the solid phase. 3. Suspended in PP, 1 and 2, about tl and h and her, so as to contain oxide grains of belts with the following distribution of zeen in fractions, wt.%: 0.01-0.02 μm 0.02-0.03 μm 0.03-0.04 μm 0.04-0.05 μm 0.05-0.06 μm 0.06-0.08 μm 0 , 08-1.0 microns 0.1-1 microns 1-10 microns 10-20 microns 20-40 microns microns 0.5 0.5 0.4 0.2 0.5 0.6 0.5 17.0 42.0 20.0 15.0 3.0, Table 1