RU2381191C2 - Organic mineral modifying agent of gypsum binding agents, building solutions, concretes, and products on their base - Google Patents

Abstract

FIELD: construction industry.

SUBSTANCE: invention refers to construction materials and can be used during manufacture of gypsum binding, building solutions, concretes and products on their base. Modifying agent includes the following, wt %: hydraulic binding agent 42 - 76, active mineral component - microsilica and fine silica-containing component 8 - 48, plasticising agent 2.1 - 11.4, setting time control 0.23 - 3.8, stabilising agent - water-soluble cellulose ester with viscosity of 5000-20000 MPa·s with 0.01 - 1.5. Invention has been developed in depending claims.

EFFECT: increasing strength, crack resistance and durability of modified gypsum binding agent, building solutions and concretes on their base, reducing power consumption.

13 cl, 1 tbl, 10 ex

Description

The invention relates to the field of building materials, namely, additives used in the production and use of gypsum binders, mortars, concrete and products based on them.

Known additive for the modification of gypsum binders containing lime, silica fume and superplasticizer C-3, obtained on the basis of sodium salts of the condensation product of naphthalene sulfonic acid and formaldehyde, in the following ratio of components (wt.% Of the modified binder):

lime (calcium oxide) 8-9;

silica fume 10-12;

superplasticizer S-3 - 0.4-0.6

(RU 2081076, 1987).

The components of the additive are introduced together with a gypsum binder, increasing the processing volume. Moreover, the obtained gypsum binder has insufficient water resistance, frost resistance, insufficient softening coefficient, and has a short setting time.

A known additive for the modification of gypsum binders, including C-3 superplasticizer based on the sodium salts of the condensation product of naphthalene sulfonic acid with formaldehyde, as well as zeolite rock calcined at 800 ° C, and the battle of silicate brick, in the following ratio of the components of the additive, wt.%:

dry powder of superplasticizer S-3 - 1.5-4.0;

zeolite rock calcined at 800 ° C - 12-14;

silicate brick battle - 82-86

(RU No. 2074137, 1997).

The additive is made separately from the gypsum binder, reducing the processing volume by several times, after which it is introduced into the gypsum binder (100 wt.%) In an amount of 5-15% by weight. This additive allows you to increase the strength of gypsum binders and save up to 15% gypsum, however, for the manufacture of the additive requires significant energy consumption for the preliminary firing of zeolite rock at a temperature of 800 ° C for 8 hours and the joint grinding of zeolite rock and battle of silicate brick with dry powder of superplasticizer C- 3 in a ball mill for 1 hour. The resulting gypsum binder in this case has insufficient water resistance and frost resistance, an insufficient softening coefficient, and has a short setting time.

Known adopted for the prototype additive for the modification of gypsum binders (RU No. 2260572 С04В 11/30, 2005), containing, wt.%:

hydraulic binder - 50-90,

active mineral component - 10-45,

plasticizing additive 0.1-2,

setting and hardening time regulator - 0.001-1,

the stabilizer is 0.001-5.

The specific surface area of the additive is 550-7000 m ² / kg. However, with this ratio of components, the durability and crack resistance of the hardened modified binder, mortars and concrete based on it are not always ensured, and obtaining the specified specific surface requires high energy costs.

The objective of the invention is to obtain a modifier that improves the physicomechanical properties of modified gypsum binders, mortars and concrete based on them, including durability, simplifying the technology of using the modifier in the production of modified gypsum binders, mortar and concrete based on them with specified improved consumer properties, as well as its implementation in industry.

The technical result obtained by using the invention is to increase the strength, crack resistance and durability of modified gypsum binders, mortars and concrete based on them, reducing energy consumption for the production of binders and products based on them.

The technical result is obtained due to the fact that the proposed modifier of gypsum binders, mortars, concretes and products based on them includes: a hydraulic binder, an active mineral component, in which it contains microsilica and a finely divided silica-containing component, a plasticizing additive, a setting time regulator and a stabilizer for the following ratio of components, wt.%: hydraulic binder - 42-76; active mineral component - 8-48; plasticizing additive - 2.1-11.4; setting time regulator - 0.23-3.8; the stabilizer is 0.01-1.5. Moreover, as a hydraulic binder, the additive contains Portland cement of any kind, white cement, colored cement, hydraulic lime; as a finely dispersed silica-containing component - quartz sand, fly ash, ash and slag mixtures of thermal power plants, blast-furnace acid granular slags, ceramic dust, ceramic brick and other ceramic products, glass break, tuff or their mixture in any proportion, as a plasticizing additive - superplasticizers , for example, based on the sodium salts of the condensation product of naphthalene sulfonic acid with formaldehyde (superplasticizer C-3 according to TU 5870-006-58042865-05), based on sulfonated melamine-formaldehyde compounds ( MF-AR produced by the Russian Federation, Melment and Izola FM-86 manufactured by the Federal Republic of Germany and others)., Based on water-soluble carboxylate polymers (FOX-8H produced by the Federal Republic of Germany, WPS-600 manufactured by the PRC, etc.), or technical lignosulfonate, or any mixture thereof in any proportion, as a set point regulator - a gypsum set retarder, for example tartaric acid, as a stabilizer - water-soluble cellulose ethers (for example, methyl cellulose, hydroxyethyl cellulose and mixed cellulose ethers of both domestic production and imported brands “BENECEL”, “CULMINAL”, etc.). As gypsum binders, semi-aquatic gypsum, or anhydrite, or a mixture thereof is used. The modifier is introduced into a gypsum or anhydrite binder or a mixture thereof in an amount of 15.0-50.0% of their weight, and the specific surface area of the modifier is 450-1200 m ² / kg.

In practice, the additive for the modification of gypsum binders, mortars and concrete based on them contains the following components, wt.%:

hydraulic binder - 42-76;

active mineral component 8-48, of which the mineral filler is 4.5-8.8;

plasticizing additive - 2.1-11.4;

setting time regulator - 0.23-3.8;

the stabilizer is 0.01-1.5.

The value of the specific surface is selected in the range from 450 m ² / kg to 1200 m ² / kg. As a gypsum binder, semi-aquatic gypsum or anhydrite is used.

If fly ash is used in the active mineral component as a finely dispersed silica-containing component, then its mass ratio to silica fume is 4-8: 1, ground silica sand is used with a silica ratio of 2-3: 1, ground slag is 4-6 : 1, ground glass battle - 2-5: 1, ground battle of ceramic waste - 1-3: 1.

The production of a modifier for gypsum binders, mortars and concrete based on them includes the following operations. The dosed components of the modifier are fed into the mill (rod, vibration, centrifugal shock, disintegrator, etc.) in the following sequence: silica-containing component, hydraulic binder, superplasticizer, silica fume, setting regulator, stabilizer, where they are ground to the required specific surface. The resulting modifier is packaged in containers for shipment to the consumer. The dosage of the additive is carried out in an amount of 15-50% by weight of the gypsum binder.

To illustrate the receipt of a modified gypsum binder, examples of specific performance are given below, moreover, semi-aquatic gypsum of the G-15 grade is used as semi-aquatic gypsum.

Example 1

For experimental verification of the claimed composition of the modifying additive, the following mixture of ingredients was prepared, wt.%:

1) gypsum binder - semi-aquatic gypsum - 70;

2) a modifier with a specific surface area of 750 m ² / kg-30,

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 70.0;

2) active mineral component:

silica fume with a specific surface of 1800 m ² / kg - 8;

silica-containing component - ground quartz sand with a specific surface area of 650 m ² / kg-16;

3) plasticizing additive - superplasticizer C-3 - 4.75;

4) gypsum setting retarder - technical tartaric acid - 0.625;

5) the stabilizer is methyl cellulose grade MT with a viscosity of 5000 MPa · s - 0.625,

The resulting composition has low water demand and high physical and mechanical properties (see table).

Example 2

For experimental verification of the claimed composition of the modifying additive, the following mixture of ingredients was prepared, wt.%:

1) gypsum binder - semi-aquatic gypsum - 80;

2) a modifier with a specific surface area of 750 m ² / kg - 20,

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 63.75;

2) active mineral component:

silica fume with a specific surface of 1800 m ² / kg - 7.5;

silica-containing component - ground quartz sand with a specific surface area of 650 m ² / kg - 22.5;

3) plasticizing additive - superplasticizer S-3 - 5.0;

4) gypsum setting retarder - technical tartaric acid - 0.625;

5) the stabilizer is methyl cellulose grade MT with a viscosity of 5000 MPa · s -0.625.

The resulting composition has low water demand and high physical and mechanical properties (see table).

Example 3

For experimental verification of the claimed composition of the modifier was prepared the following mixture of ingredients, wt.%:

1) gypsum binder - semi-aquatic gypsum - 70;

2) a modifier with a specific surface of 970 m ² / kg - 30;

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 67;

2) active mineral component:

silica fume with a specific surface of 1800 m ² / kg - 5.1;

silica-containing component - fly ash - 23.0;

3) plasticizing additive - superplasticizer C-3 - 4.2;

4) gypsum setting retarder - technical tartaric acid - 0.55;

5) the stabilizer is methyl cellulose grade MT with a viscosity of 5000 MPa · s - 0.15.

The resulting composition has improved physical and mechanical properties (frost resistance, strength, water resistance), in this regard, the scope of use of a binder, including for outdoor structures, is expanding.

Example 4

For experimental verification of the claimed composition of the modifier was prepared the following mixture of ingredients, wt.%:

1) gypsum binder - semi-aquatic gypsum - 60;

2) a modifier with a specific surface of 500 m ² / kg - 40;

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 58;

2) active mineral component:

silica fume with a specific surface of 1800 m ² / kg - 7.8;

silica-containing filler, blast furnace granulated slag with a specific surface of 480 m ² / kg - 29.4;

3) plasticizing additive - superplasticizer C-3 + technical lignosulfonate in a ratio of 1: 1 - 2.46;

4) gypsum hardening inhibitor, technical tartaric acid - 2.1;

5) stabilizer, methyl cellulose grade MT with a viscosity of 5000 MPa · s - 0.24.

The resulting composition has high water resistance and strength.

Example 5

For experimental verification of the claimed composition of the modifying additive, the following mixture of ingredients was prepared, wt.%:

1) gypsum binder - semi-aquatic gypsum - 70;

2) a modifier with a specific surface area of 750 m ² / kg - 30,

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement white - 64;

2) active mineral component:

silica fume with a specific surface of 1,500 m ² / kg - 7.5;

silica-containing component - ground cullet with a specific surface of 950 m ² / kg - 22.5;

3) plasticizing additive - carboxylate-based hyperplasticizer - 5.0;

4) gypsum setting retarder, technical tartaric acid - 0.5;

5) stabilizer - cellulose ether "Culminal" with a viscosity of 10,000 MPa · s - 0.5.

The resulting composition has low water demand and high physical and mechanical properties (see table).

Example 6

For experimental verification of the claimed composition of the modifying additive, the following mixture of ingredients was prepared, wt.%:

1) gypsum binder - semi-aquatic gypsum - 60;

2) a modifier with a specific surface of 750 m ² / kg - 40,

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 69;

2) active mineral component:

silica fume - 8.5;

silica-containing filler - ground battle of ceramic waste (expanded clay dust from electrostatic precipitators) with a specific surface area of 650 m ² / kg - 17;

3) plasticizing additive - superplasticizer, obtained on the basis of sulfonated naphthalene formaldehyde compounds (C-3) - 5.0;

4) gypsum setting retarder, technical tartaric acid - 0.275;

5) stabilizer, cellulose ether METOCEL ("METHOCEL") with a viscosity of 7000 MPa · s - 0.225.

The resulting composition has low water demand and high physical and mechanical properties (see table).

Example 7

For experimental verification of the claimed composition of the modifying additive, the following mixture of ingredients was prepared, wt.%:

1) gypsum binder - semi-aquatic gypsum - 70;

2) a modifier with a specific surface area of 750 m ² / kg - 30,

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 53;

2) active mineral component:

silica fume - 4.5;

silica-containing filler, fly ash - 36;

3) plasticizing additive - superplasticizer, obtained on the basis of sulfonated melamine-formaldehyde compounds (MF-AR) - 4.4;

4) gypsum setting retarder, technical tartaric acid - 0.65;

5) stabilizer, cellulose ether "METHOCEL" with a viscosity of 7000 MPa · s - 1.45.

The resulting composition has low water demand and high physical and mechanical properties (see table).

Example 8

For experimental verification of the claimed composition of the modifier was prepared the following mixture of ingredients, wt.%:

1) gypsum binder - semi-aquatic gypsum - 70;

2) a modifier with a specific surface area of 550 m ² / kg - 30;

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 53;

2) active mineral component:

silica fume - 6;

silica-containing component - blast furnace granulated slag with a specific surface of 420 m ² / kg - 36;

3) a plasticizing additive - a superplasticizer, obtained on the basis of sulfonated naphthalene formaldehyde compounds (C-3) + technical lignosulfonate in a ratio of 1 to 2 - 2.75;

4) gypsum setting retarder - technical tartaric acid - 2;

5) the stabilizer is ethyloxyethyl cellulose (EOEC) with a viscosity of 15000 MPa · s - 0.25.

Despite the fact that the gypsum binder modifier contains only 46% of the hydraulic binder, the resulting composition has high water resistance and strength.

Example 9

For experimental verification of the claimed composition of the modifier was prepared the following mixture of ingredients, wt.%:

1) gypsum binder - semi-aquatic gypsum - 70;

2) a modifier with a specific surface area of 550 m ² / kg - 30;

wherein the modifier of the following composition, wt.%:

1) hydraulic binder, Portland cement - 53;

2) active mineral component:

silica fume - 6;

silica-containing component - blast furnace granulated slag with a specific surface of 420 m ² / kg - 36;

3) plasticizing additive - a plasticizer obtained on the basis of modified lignosulfonates (BPS BV-1) - 2.75;

4) gypsum setting retarder - technical tartaric acid - 2;

5) the stabilizer is ethyloxyethyl cellulose (EOEC) with a viscosity of 15000 MPa · s - 0.25.

Despite the fact that the gypsum binder modifier contains only 46% of the hydraulic binder, the resulting composition has high water resistance and strength.

The composition of the modifier in accordance with the prototype.

1) gypsum binder - semi-aquatic gypsum - 70;

2) an additive for the modification of gypsum with a specific surface of 4000 cm ² / kg - 30;

wherein the addition of the following composition, wt.%:

1) hydraulic binder, Portland cement - 87.9;

2) active mineral component, silica fume - 10;

3) a superplasticizer based on polycarboxylates - 1;

4) a gypsum hardening inhibitor, natural tartaric acid - 0.1;

5) water-soluble cellulose ether - hydroxyethyl cellulose - 1.

For the experimental determination of the parameters of the claimed composition, samples were made in the form of prisms 40 × 40 × 160 mm in size. The test results are shown in the table.

Name of indicator The composition according to the example, wt.% one 2 3 four 5 6 7 8 9 Prototype Water demand (water-solid ratio) at 180 mm spread 0.22 0.21 0.20 0.22 0.19 0.22 0.19 0.20 0.24 0.18 Setting time Start 5 39 38 34 22 eighteen 22 33 41 thirty end 35 53 62 58 54 56 65 60 65 60 Compressive strength at the age of 3 days, MPa 28.0 29.5 27.5 17.0 18.0 21.0 19 twenty 17 19.5 Compression strength at the age of 28 days, MPa during hardening in wet conditions 42.3 44.7 45.8 33.0 48.5 38,0 42 45 37 35 Softening coefficient 0.83 0.92 0.95 0.88 0.93 0.89 0.85 0.89 0.84 0.82 Viability (onset of loss of mobility), min twenty 35 35 33 twenty 22 23 19 33 fifteen Crack resistance *, the amount of deformation of the samples at 3-month hardening in water,% +0.18 +0.21 +0.19 +0.12 +0.13 +0.14 +0.12 +0.13 +0.10 0.45 Note: Crack resistance is sufficient if the strain does not exceed 0.25% for 3 months of curing of samples in water.

Claims (13)

1. A modifier for gypsum binders, mortars, concrete and products based on them, including a hydraulic binder, an active mineral component, a plasticizing agent, setting agent and stabilizer, characterized in that it contains microsilica and a finely divided silica-containing component as an active mineral component, and as a stabilizer - water-soluble cellulose ether with a viscosity of 5000-20000 MPa · s, with the following ratio of components, wt.%:
Hydraulic binder 42-76 Active mineral component 8-48 Plasticizing additive 2.1-11.4 Setting time adjuster 0.23-3.8 Specified stabilizer 0.01-1.5 2. The modifier according to claim 1, characterized in that it is characterized by a specific surface area of 450 to 1200 m ² / kg. 3. The modifier according to claim 1, characterized in that as a finely divided silica-containing component contains fly ash in the ratio of silica fume 4-8: 1. 4. The modifier according to claim 1, characterized in that as a finely divided silica-containing component contains ground silica sand with a ratio of silica fume 2-3: 1. 5. The modifier according to claim 1, characterized in that, as a finely divided silica-containing component, it contains ground slag at a ratio of 4-6: 1 to silica fume. 6. The modifier according to claim 1, characterized in that, as a finely divided silica-containing component, it contains ground glass battle with a ratio of 2-5: 1 to silica fume. 7. The modifier according to claim 1, characterized in that as a finely divided silica-containing component contains ground battle of ceramic waste with a ratio of silica fume 1-3: 1. 8. The modifier according to claim 1, characterized in that it contains as a plasticizing additive a superplasticizer obtained on the basis of sulfonated naphthalene formaldehyde compounds. 9. The modifier according to claim 1, characterized in that it contains as a plasticizing additive a superplasticizer obtained on the basis of sulfonated melamine-formaldehyde compounds. 10. The modifier according to claim 1, characterized in that it contains, as a plasticizing additive, a superplasticizer and a technical lignosulfonate in any ratio. 11. The modifier according to claim 1, characterized in that it contains technical lignosulfonate as a plasticizing additive. 12. The modifier according to claim 1, characterized in that it contains as a plasticizing additive a superplasticizer based on modified lignosulfonates. 13. The modifier according to claim 1, characterized in that the water-soluble cellulose ether contains methyl cellulose.