CN110803938A - Aerogel foam concrete and preparation method and application thereof - Google Patents

Abstract

The invention belongs to the field of building materials, and particularly relates to aerogel foam concrete and a preparation method and application thereof. According to the invention, the aerogel slurry is added into the concrete, so that the heat insulation, heat preservation and sound insulation properties of the foam concrete can be enhanced, the dry density of the foam concrete can be reduced on the premise of not reducing the compactness, and the foam concrete with low density, stronger formability and good compressive strength can be obtained under the condition of low porosity.

Description

Aerogel foam concrete and preparation method and application thereof

Technical Field

The invention belongs to the field of building materials, and particularly relates to aerogel foam concrete and a preparation method and application thereof.

Background

According to the report of Freedonia research company, the total value of the heat-insulating material in China is about 1200 million yuan at present, and the market scale of the heat-insulating material can reach 3000 million yuan in 2020. Wherein the application ratio in the industrial field reaches 1/3, and the application ratio in the building field reaches 2/3. The global annual growth rate of the heat-insulating material is 6.3 percent. More than 90 percent of houses with nearly 20 hundred million square meters are still high-energy-consumption buildings newly built in China every year. Therefore, the problem of building energy conservation is highly emphasized, the building energy consumption is greatly reduced, and the sustainable development of social construction and national economy is realized.

Foam concrete is commonly called foam cement, lightweight concrete and the like. The foam concrete is characterized in that closed foam holes are formed in the concrete, and the concrete is endowed with light weight and heat insulation performance. The foam concrete is applied to building floors and walls, can effectively enhance the thermal insulation performance of buildings and reduce the self weight of the buildings, and has the characteristics of non-combustibility, difficult shedding, durability and the like. The grades of foamed concrete products are classified according to dry density and compressive strength in national standards. The smaller the dry density, the better the thermal insulation performance of the foam concrete, and the compressive strength reflects the firmness of the foam concrete.

From the analysis of the preparation principle of the foam concrete, the functions of light weight, sound insulation, heat preservation, fluidity and the like which are not possessed by the common cement are provided by utilizing a large amount of air holes introduced by the foaming agent, which is the basis of the preparation of the foam concrete, but from the aspects of structure and mechanical properties, the structural compactness is greatly reduced, so that the strength of the foam concrete is reduced. How to realize the functions of light weight, sound insulation, heat preservation and the like, and the strength of the concrete is not lower than the expected target is a difficulty in concrete scientific research and production.

SiO₂Aerogel is a structure-controllable nano-porous light material, and is the lightest solid substance known at present. The application value in the fields of heat preservation, heat insulation, sound insulation and the like is well recognized. The aerogel is introduced into the foam concrete to prepare the aerogel foam concrete, so that the heat insulation performance, the sound insulation performance and the strength of the foam concrete can be effectively enhanced on the premise of not reducing the compactness of the material, the density of the foam concrete is reduced, and the aerogel foam concrete has the characteristics of fire resistance, difficulty in falling, durability and the like.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides aerogel foam concrete and a preparation method and application thereof.

The technical scheme provided by the invention is as follows:

the aerogel foam concrete comprises the following components in parts by weight:

wherein the volume ratio of bubbles in the aerogel foam concrete is 45-55 vt%.

The volume ratio of the bubbles is: the volume ratio of air bubbles in the aerogel foam concrete to the aerogel foam concrete.

Based on the technical scheme, the aerogel slurry is added, so that the heat insulation, heat preservation and sound insulation performance of the foam concrete can be enhanced, the dry density of the foam concrete can be reduced on the premise of not reducing the compactness, and the foam concrete with low density, strong formability and good compressive strength can be obtained under the condition of low porosity.

Specifically, the cement is selected from one or more of portland cement, ordinary portland cement, portland slag cement, pozzolanic portland cement, portland fly ash cement and the like.

The hydraulic cementing material is made up by grinding Portland cement clinker, 5% -20% of mixed material and proper quantity of gypsum, and is the ordinary Portland cement.

Specifically, the foaming agent is an inorganic foaming agent or an organic foaming agent.

Based on the technical scheme, the system is mainly an inorganic system, so that the fireproof flame-retardant material has certain fireproof performance and flame retardance.

Specifically, the foaming agent is any one or a mixture of more of a rosin foaming agent, a synthetic surfactant foaming agent, a vegetable protein foaming agent, an animal protein foaming agent, sodium peroxycarbonate, hydrogen peroxide, an ammonium bicarbonate foaming agent, an azodicarbonamide foaming agent and an aluminum powder foaming agent.

Specifically, the thickening agent is selected from one or more of hydroxypropyl methyl cellulose, hydroxyethyl methyl cellulose, poly cellulose, lignocellulose, cellulose ether, hydroxyethyl cellulose or carboxymethyl cellulose.

Specifically, the aerogel in the aerogel slurry is hydrophobic aerogel; the solvent in the aerogel slurry is water.

Based on the technical scheme, the hydrophobic aerogel is added, so that the water absorption rate of the foam concrete is reduced, and the use of a water repellent is avoided

Specifically, the hydrophobic aerogel is selected from any one or more of silicon dioxide aerogel, aluminum oxide aerogel, titanium dioxide aerogel or carbon aerogel.

Specifically, the inorganic reinforcing fibers are selected from one or more of glass fibers, ceramic fibers, basalt fibers, alumina fibers and carbon fibers.

Based on the technical scheme, the system is mainly an inorganic system, so that the fireproof flame-retardant material has certain fireproof performance and flame retardance.

The invention also provides a preparation method of the aerogel foam concrete, which comprises the following steps:

1) uniformly dry-mixing the cement and the inorganic reinforced fiber according to the formula amount, adding 50-70% of water according to the formula amount, uniformly mixing, adding the aerogel slurry according to the formula amount, and uniformly mixing to prepare cement fiber aerogel slurry;

2) uniformly mixing the rest water with the formula amount and the foaming agent to generate foam;

3) adding the foam prepared in the step 2) into the cement fiber aerogel slurry prepared in the step 1), and stirring and mixing uniformly to obtain mixed slurry;

4) pouring the mixed slurry prepared in the step 3) into a mould, and sequentially carrying out mould reversing, mould removing and finished product maintenance to obtain the aerogel foam concrete.

The technical scheme is convenient to implement, not only can produce various products in a factory, but also can be constructed on site and directly cast into a roof, a ground and a wall in situ.

The invention also provides an application of the aerogel foam concrete as an aerogel foam concrete building block.

The application of the aerogel foam concrete provided by the invention has good heat insulation and heat preservation performance and sound insulation performance, lower dry density, stronger formability and good compressive strength, and has certain fire resistance and fire resistance.

Detailed Description

The principles and features of this invention are described below in conjunction with examples which are set forth to illustrate, but are not to be construed to limit the scope of the invention.

Example 1

Preparation of aerogel foam concrete

1) Uniformly mixing the cement and the inorganic reinforced fiber in the formula amount in a dry mode, then adding part of water in the formula amount in the dry mode, uniformly mixing, then adding the aerogel slurry in the formula amount in the dry mode, and uniformly mixing to obtain cement fiber aerogel slurry;

2) uniformly mixing the rest water with the formula amount and the foaming agent to generate foam;

3) adding the foam prepared in the step 2) into the cement fiber aerogel slurry prepared in the step 1), and stirring and mixing uniformly to obtain mixed slurry.

4) Pouring the mixed slurry prepared in the step 3) into a mould, and sequentially performing mould reversing, mould removing and finished product maintenance to obtain the aerogel foam concrete 1.

Wherein: 200 parts of Portland cement, 30 parts of glass fiber, 50 parts of aerogel slurry, 18% of aerogel slurry by mass, silica aerogel serving as aerogel, water serving as a solvent of the aerogel slurry, 150 parts of water, 0.05 part of hydroxypropyl methyl cellulose and 15 parts of rosin foaming agent. The bubble volume ratio of the obtained aerogel foam concrete was 45 vt%.

Example 2

Preparation of aerogel foam concrete

1) Uniformly mixing the cement and the inorganic reinforced fiber in the formula amount in a dry mode, then adding part of water in the formula amount in the dry mode, uniformly mixing, then adding the aerogel slurry in the formula amount in the dry mode, and uniformly mixing to obtain cement fiber aerogel slurry;

2) uniformly mixing the rest water with the formula amount and the foaming agent to generate foam;

3) adding the foam prepared in the step 2) into the cement fiber aerogel slurry prepared in the step 1), and stirring and mixing uniformly to obtain mixed slurry.

4) Pouring the mixed slurry prepared in the step 3) into a mould, and sequentially performing mould reversing, mould removing and finished product maintenance to obtain the aerogel foam concrete 2.

Wherein: 250 parts of ordinary portland cement, 40 parts of ceramic fiber and 55 parts of aerogel slurry, wherein the mass fraction of the aerogel slurry is 20 wt%, the aerogel is aluminum oxide aerogel, and the solvent of the aerogel slurry is water. 170 parts of water, 0.1 part of hydroxyethyl methyl cellulose, 30 parts of foaming agent and synthetic surfactant foaming agent.

The resulting aerogel foam concrete had a bubble volume ratio of 50 vt%.

Example 3

Preparation of aerogel foam concrete

1) Uniformly mixing the cement and the inorganic reinforced fiber in the formula amount in a dry mode, then adding part of water in the formula amount in the dry mode, uniformly mixing, then adding the aerogel slurry in the formula amount in the dry mode, and uniformly mixing to obtain cement fiber aerogel slurry;

2) uniformly mixing the rest water with the formula amount and the foaming agent to generate foam;

3) adding the foam prepared in the step 2) into the cement fiber aerogel slurry prepared in the step 1), and stirring and mixing uniformly to obtain mixed slurry.

4) Pouring the mixed slurry prepared in the step 3) into a mould, and sequentially performing mould reversing, mould removing and finished product maintenance to obtain the aerogel foam concrete 3.

Wherein: 300 parts of fly ash Portland cement, 50 parts of alumina fiber and 60 parts of aerogel slurry, wherein the mass fraction of the aerogel slurry is 22 wt%, the aerogel is titanium dioxide aerogel, and the solvent of the aerogel slurry is water. 200 parts of water and 0.2 part of hydroxyethyl cellulose; 45 parts of foaming agent, and the foaming agent is hydrogen peroxide.

The resulting aerogel foam concrete had a bubble volume ratio of 53 vt%.

Comparative example 1

The procedure is as in example 1, except that no aerogel slurry is added to give a foamed concrete 1.

Comparative example 2

The procedure is as in example 2, except that no aerogel slurry is added to give a foamed concrete 2.

Comparative example 3

The procedure is as in example 3, except that no aerogel slurry is added to give a foamed concrete 3.

Comparative example 4

The embodiment is the same as example 1 except that the aerogel slurry is added in an amount of 10 wt%. To obtain the foam concrete 4.

Test data:

respectively carrying out performance tests on the aerogel foam concrete 1, the aerogel foam concrete 2, the aerogel foam concrete 3, the foam concrete 1, the foam concrete 2 and the foam concrete 3, wherein the test contents comprise:

heat insulation performance: and testing the heat conductivity coefficient according to a heat flow meter method for measuring the steady-state thermal resistance and related characteristics of the heat-insulating material in GB/T10295 and 2008.

Dry density: the test was performed according to JG/T266-2011;

compressive strength: the test was performed according to JG/T266-2011.

Limit of fire resistance: the test was carried out according to GB/T50016.

The results are statistically as follows:

the data show that the thermal insulation performance of the foam concrete can be improved by adding the aerogel slurry, and the compressive strength of the foam concrete can be increased; the aerogel slurry concentration decreases, resulting in an increase in the thermal conductivity and a decrease in the strength of the foamed concrete.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims (10)

1. The aerogel foam concrete is characterized by comprising the following components in parts by weight:

wherein the volume ratio of bubbles in the aerogel foam concrete is 45-55 vt%.

2. The aerogel foam concrete according to claim 1, wherein: the cement is selected from any one or more of ordinary portland cement, slag portland cement, pozzolanic portland cement, or fly ash portland cement.

3. The aerogel foam concrete according to claim 1, wherein: the foaming agent is an inorganic foaming agent or an organic foaming agent.

4. The aerogel foam concrete according to claim 3, wherein: the foaming agent is any one or a mixture of more of a rosin foaming agent, a synthetic surfactant foaming agent, a vegetable protein foaming agent, an animal protein foaming agent, sodium peroxycarbonate, hydrogen peroxide, an ammonium bicarbonate foaming agent, an azodicarbonamide foaming agent and an aluminum powder foaming agent.

5. The aerogel foam concrete according to claim 1, wherein: the thickening agent is selected from one or more of hydroxypropyl methylcellulose, hydroxyethyl methylcellulose, polymeric cellulose, lignocellulose, cellulose ether, hydroxyethyl cellulose or carboxymethyl cellulose.

6. The aerogel foam concrete according to claim 1, wherein: the aerogel in the aerogel slurry is hydrophobic aerogel; the solvent in the aerogel slurry is water.

7. The aerogel foam concrete according to claim 6, wherein: the hydrophobic aerogel is selected from any one or more of silicon dioxide aerogel, aluminum oxide aerogel, titanium dioxide aerogel or carbon aerogel.

8. The aerogel foam concrete according to claim 1, wherein: the inorganic reinforcing fiber is selected from one or more of glass fiber, ceramic fiber, basalt fiber, alumina fiber and carbon fiber.

9. A method of producing an aerogel foam concrete according to any one of claims 1 to 8, comprising the steps of:

1) uniformly dry-mixing the cement and the inorganic reinforced fiber according to the formula amount, adding 50-70% of water according to the formula amount, uniformly mixing, adding the aerogel slurry according to the formula amount, and uniformly mixing to prepare cement fiber aerogel slurry;

2) uniformly mixing the rest water with the formula amount and the foaming agent to generate foam;

3) adding the foam prepared in the step 2) into the cement fiber aerogel slurry prepared in the step 1), and stirring and mixing uniformly to obtain mixed slurry;

4) pouring the mixed slurry prepared in the step 3) into a mould, and sequentially carrying out mould reversing, mould removing and finished product maintenance to obtain the aerogel foam concrete.

10. Use of an aerogel foam concrete according to any one of claims 1 to 9, characterized in that: as an aerogel foam concrete block.