Self-insulation building block and preparation method thereof

Abstract

The application belongs to the field of building materials, and particularly relates to a self-thermal-insulation block and a preparation method thereof. The method comprises the following steps: 1) preparing a base material, sintering the base material into a coarse blank and sand material; 2) preparing a silicon modified material, mixing the silicon modified material and the sand material into a closed material and a fine material at a mass ratio of 1:(2.8-3.2) and 1:(1.3-1.7) respectively; 3) coating the closed material prepared in the step 2) on opposite two surfaces of the coarse blank prepared in the step 1), and sintering at high temperature to form a closed layer to obtain a coarse block, coating the fine material prepared in the step 2) on four surfaces of the coarse block, and sintering at low temperature to form a functional surface layer to obtain the self-thermal-insulation block. The self-thermal-insulation block has good thermal insulation effect, and the mechanical properties of the self-thermal-insulation block are improved, the actual thermal insulation performance of the wall formed by the self-thermal-insulation block is improved, the actual heat shock resistance of the block is ensured, and the service life of the self-thermal-insulation block is prolonged.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of building materials, and particularly relates to a self-insulation block and a preparation method thereof. BACKGROUND

[0002] The self-insulation block is a prefabricated material mainly used for wall construction, has the advantages of light weight and high sound absorption efficiency, and is classified into self-insulation blocks of concrete, cement mortar, aerated concrete, fly ash silicate, coal gangue, artificial ceramsite, and slag waste according to materials, and can be made into walls, insulation blocks, and floors, and has high efficiency in construction and is convenient to build.

[0003] The blocks produced by using new wall materials sintered from river and lake sludge, fly ash, slag, coal gangue and other materials or the blocks made from waste materials have been fully utilized in China. For example, CN104529309A discloses a non-load-bearing self-insulation block and a preparation method thereof, the self-insulation block comprises the following raw materials in parts by weight: 30-40 parts of fly ash, 10-15 parts of stone chips, 10-15 parts of cement, 15-20 parts of aerated concrete construction waste, and 8-10 parts of YT inorganic active insulation material, realizes waste recycling, saves resources, is beneficial to reducing the self-weight of the self-insulation block, and the main component is the aerated concrete block crushed construction waste which replaces part of the coarse aggregate stone chips, thereby reducing the self-weight and reducing the self-weight by about 15 kg per cubic meter compared with similar products.

[0004] However, the current self-insulation block has sufficient insulation performance itself, but the insulation performance after being actually built into a wall is limited. According to test detection, especially at the cement filling part between the wall joints and the brick joints, since the thermal conductivity of the cement is generally greater than that of the self-insulation block, the insulation performance is particularly insufficient. Most of the current self-insulation blocks are filled with organic fillers as heat-absorbing and energy-storing materials to improve the defects of the insufficient strength of the porous structure of the traditional self-insulation block, and it is believed that the actual heat storage and insulation capacity of the organic filler is better than that of the traditional porous structure. However, the actual service life of the organic filler self-insulation block is much shorter than that of the porous structure self-insulation block. Because in the working process, the actual self-insulation block is in a process of continuous heating and cooling, and since the organic filler self-insulation block is a full solid material, there is a difference in the expansion coefficient between the base material and the organic filler during the heating and cooling process. Although the organic filler generally has a certain elastic deformation capacity to adapt to the extrusion of the base material to maintain its filling in the early stage, with the extension of the use time, cracks and fissures are easily generated, and the cracks and fissures extend from the surface of the block to the deep inside, thus actual “acquired” open cracks are generated, which greatly reduces the insulation performance of the self-insulation block. SUMMARY

[0005] In order to solve the problems of the relatively limited mechanical property of the traditional porous self-insulation block, the short service life of the organic filling type self-insulation block, and the significant decrease of the thermal insulation property after the cold and hot alternation, the application provides a self-insulation block and a preparation method of the self-insulation block.

[0006] The application aims at:

[0007] I. improving the mechanical property of the self-insulation block;

[0008] II. improving the thermal insulation property of the wall body after the self-insulation block is used to build the wall body;

[0009] III. effectively improving the service life of the self-insulation block.

[0010] In order to achieve the above-mentioned purpose, the application adopts the following technical scheme.

[0011] A preparation method of a self-insulation block,

[0012] The method comprises:

[0013] 1) preparing a base material, sintering the base material into a coarse blank and sand material;

[0014] 2) preparing a silicon modified material, mixing the silicon modified material and the sand material into a closed material and a refining material with the mass ratio of 1:(2.8-3.2) and 1:(1.3-1.7) respectively;

[0015] 3) coating the closed material prepared in the step 2) on the opposite two surfaces of the coarse blank prepared in the step 1), sintering at high temperature to form a closed layer to obtain a coarse block, coating the refining material prepared in the step 2) on the four surfaces of the coarse block without the closed layer, sintering at low temperature to form a functional surface layer to obtain a self-insulation block.

[0016] As a preferred,

[0017] The base material in the step 1) is composed of 6-12wt% foaming agent, 22-28wt% clay, 4-8wt% mineral wool, 30-50wt% stone slag and the rest water;

[0018] The sintering in the step 1) is sintered at 950-1100℃ for 3-5h.

[0019] As a preferred,

[0020] The foaming agent is composed of 25-35wt% calcium sulfate, 5-15wt% sodium oxide and the rest barium carbonate;

[0021] The mineral wool is slag wool and / or rock wool and / or glass wool and / or aluminum silicate refractory fiber;

[0022] The stone slag is perlite and / or shale and / or pyroclastic rock and / or coal gangue.

[0023] As preferred,

[0024] The silicon-modified material of step 2) comprises 20-28 wt% of silicate, 25-32 wt% of organosilicon, 0.3-0.8 wt% of coagulant, 0.5-1 wt% of antioxidant, and the balance of water.

[0025] As preferred,

[0026] The organosilicon is dimethylsilanediol;

[0027] The coagulant is sodium formate;

[0028] The antioxidant is 3,4,5,7-tetrahydroxyflavone.

[0029] As preferred,

[0030] The coating amount of the sealing material in step 3) is 150-200 g / m 2 .

[0031] The coating amount of the refined material prepared in step 2) in step 3) is 180-220 g / m 2 .

[0032] As preferred,

[0033] The high-temperature sintering in step 3) is controlled at 600-800 ℃ for 60-120 min.

[0034] As preferred,

[0035] The low-pressure sintering is performed under the condition of ambient pressure ≤ 0.3 atm.

[0036] As preferred,

[0037] The low-temperature sintering in step 3) is controlled at 200-300 ℃ for 45-75 min.

[0038] A self-insulation building block.

[0039] In the present application, unlike the traditional self-insulation building block, the present application does not directly prepare a high-closed-porosity closed-porosity brick body as the target in the preparation process of the early-stage rough block, but cooperates with an inorganic foaming agent to prepare a high-open-porosity rough block in the early stage. Compared with directly preparing a closed-porosity brick, preparing an open-porosity brick first is more conducive to forming a higher porosity and more ordered pore structure in the brick body, which is a basic guarantee for subsequent improvement of the thermal insulation performance and mechanical properties of the brick body.

[0040] On this basis, the application carries out closed treatment on the plaster layer of the brick. Because the main requirement of the self-insulation block is the insulation performance, which is the conduction between the two sides of the wall, the closed plaster layer can realize the insulation of the gas exchange between the two sides, so as to form the cavity type heat insulation effect. At the same time, the preparation of the closed layer can form a solid structure and absolute closure, so that the mechanical properties and insulation performance of the brick are significantly improved. Compared with the traditional pore type self-insulation block, the application improves the limit closed porosity of the plaster layer of the self-insulation block from about 95% to 100%, and forms the solid support on the two sides, so that the overall structural strength of the self-insulation block is guaranteed.

[0041] As for the preparation of the closed layer of the application, it is not directly and simply coated with a layer of closed material, but the coarse blank is used for joint preparation, the coarse blank is crushed and ground through an 80 mesh sieve, the sand material above 80 mesh is obtained, and the sand material and the silicon modified material are matched to realize the preparation of the closed layer, so as to ensure the combination effectiveness of the closed layer and the base coarse blank, that is, to improve the bonding strength of the closed layer and the coarse blank carrier, so as to avoid the falling caused by the simple use of the remaining closed material for closing.

[0042] Meanwhile, the sealing layer of the present application is not simply formed by adhesive bonding, but is processed by specific silicon modified material. In common self-insulation blocks, especially porous self-insulation blocks, when applied, it is easy to combine with cement to produce a substance that is easy to absorb water and expand, thereby producing internal expansion self-stress and cracking phenomenon. After the silicon modified material of the present application is mixed and processed with sand material, the sand material can be modified to a certain extent. First of all, the basic role is that silicate can greatly improve the generation speed of crystalline substance as nucleation point, realize efficient solidification of surface cement, and at the same time, unlike common silicate doped in base material, it has the characteristic of surface enrichment, so that its effect of promoting cement solidification is more optimal, and on the other hand, the rapid solidification of cement can also avoid the surface efflorescence of self-insulation blocks, and enhance its surface strength and hardness. On the other hand, the organosilicon dimethylsilanediol used in the present application can effectively wet the sand material, fill the sand material inside, and form cross-linking with the sand material and silicate to generate a hydrophobic layer. The formation of the hydrophobic layer can ensure that water vapor is quickly discharged during the sintering process of the sealing layer to ensure that it is highly dense and the surface is completely closed. During the sintering process of the refined material, due to the low temperature sintering characteristics of the refined material, the hydrophobic layer can be effectively maintained to realize the rapid diffusion and penetration of cement into the self-insulation block. In addition to improving the water permeability of the finishing layer, the cement can also penetrate into the self-insulation block to improve the strength of the overall wall. Sodium formate as a coagulant can promote the formation of the hydrophobic layer, and due to the strong diffusion of carboxylate ions, when the cement penetrates and diffuses into the self-insulation block, it can migrate into the cement to promote the hydration reaction to form C-Si-H chain with silicate and organosilicon, and generate microcrystalline aggregates. The formation of microcrystalline aggregates can promote and guide the secondary distribution of cement after penetration and make it converge into fibers, ensuring that the self-insulation block can still maintain a high porosity while forming effective penetration bonding, reducing the thickness of cement between adjacent self-insulation blocks, and increasing the actual thermal insulation area.

[0043] With the cooperation of the above-mentioned silicon modified material, the sealing layer can ensure that it is highly dense and closed, has good air tightness and water permeability, and has good mechanical properties to produce greater support strength.

[0044] On the other hand, the present application uses different usage ratios to prepare the sand material and the silicon modified material into refined materials, which, compared with the closed materials, do not achieve complete closure due to filling and other factors, but form capillary structures with open pores, which can further promote the penetration of cement. The difference between the two is caused by the different relative usage of the silicon modified material and the different sintering temperatures. In the case of smaller relative usage of the silicon modified material, the silicon modified material will actually form a surface wetting coating of the sand material under the action of dimethylsilanediol, rather than complete filling, and after low-temperature sintering, due to the relatively low sintering temperature, the solidification expansion filling of the material can be avoided.

[0045] Thus, under the above structure, different surface structures can be formed on the six surfaces of the self-insulation block to improve the actual use effect of the block.

[0046] The beneficial effects of the present application are:

[0047] The present application ensures that the self-insulation block has good thermal insulation effect, improves the mechanical properties of the self-insulation block and the actual thermal insulation performance of the wall formed after the block is laid, and guarantees the actual heat shock resistance of the block, prolonging the service life of the self-insulation block. BRIEF DESCRIPTION OF DRAWINGS

[0048] Figure 1 The infrared temperature measurement photograph of the thermal insulation test of the wall formed by the self-insulation block prepared in Example 1 of the present application;

[0049] Figure 2 The infrared temperature measurement photograph of the thermal insulation test of the wall formed by the self-insulation block prepared in Example 1 of the present application;

[0050] Figure 3 The infrared temperature measurement photograph of the thermal insulation test of the wall formed by the self-insulation block prepared in Example 1 of the present application; DETAILED DESCRIPTION

[0051] The present application will be further described and illustrated in detail below in combination with specific embodiments and the accompanying drawings. Those skilled in the art will be able to implement the present application based on these descriptions. In addition, the embodiments of the present application involved in the following description are generally only a part of the embodiments of the present application, not all the embodiments. Therefore, based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor should be within the scope of protection of the present application.

[0052] In the description of the present invention, it should be understood that the terms "thickness," "upper," "lower," "horizontal," "top," "bottom," "inner," "outer," "circumferential," and the like, indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of the present invention and simplify the description. They do not indicate or imply that the devices or elements referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In the description of the present invention, "plurality" means at least two, such as two or three, and unless otherwise expressly specified, "several" means one or more.

[0053] In the present invention, unless otherwise specified or limited, the terms "installed," "connected," "connect," "fixed," etc. should be understood in a broad sense. For example, they can refer to fixed connection, detachable connection, or integration; mechanical connection, electrical connection, or communication; direct connection or indirect connection through an intermediate medium; internal communication between two elements or interaction between two elements, unless otherwise specified. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0054] Unless otherwise specified, the raw materials used in the examples of the present invention are all commercially available or available to those skilled in the art; unless otherwise specified, the methods used in the examples of the present invention are all methods known to those skilled in the art.

[0055] Example 1

[0056] A self-insulating building block is prepared by the following method:

[0057] 1) preparing a base material, wherein the base material is composed of 9 wt% of a foaming agent, 25 wt% of industrial clay, 5 wt% of rock wool, 45 wt% of coal gangue, and the balance is water, wherein the foaming agent is composed of 30 wt% of calcium sulfate, 10 wt% of sodium oxide, and 60 wt% of barium carbonate. The base material is sintered at 1050° C. for 3.5 hours to obtain a rough blank having a size of 10.5 cm×10.5 cm×10.5 cm. The rough blanks with poor appearance, such as missing corners and poor surface flatness, are selected, crushed and ground, and then passed through an 80-mesh sieve to obtain sand material;

[0058] 2) preparing a silicon modified material, which consists of 25 wt% sodium silicate, 28 wt% dimethylsilanediol, 0.5 wt% sodium formate, 1 wt% 3,4,5,7-tetrahydroxyflavone, and the balance water. The silicon modified material and sand material are mixed at a mass ratio of 1:3 and 1:1.5, respectively, to form a sealing material and a refining material;

[0059] 3) The sealing material prepared in step 2) is coated on the opposite two sides of the rough block prepared in step 1), and the coating amount is 180 g / m 2 After high-temperature sintering at 750 ℃ for 90 min, a sealing layer is formed to obtain a rough block (i.e. a sealing layer is formed on the finishing layer), and the refining material prepared in step 2) is coated on the four sides of the rough block without the sealing layer, and the coating amount is 200 g / m 2 After sintering at 280 ℃ for 60 min under a low pressure of 0.3 atm, a functional surface layer is formed to obtain a self-insulation block.

[0060] The self-insulation block is subjected to performance detection and characterization.

[0061] The characterization includes:

[0062] Wall performance test:

[0063] The self-insulation block prepared is used as a test sample, and a heat insulation performance test is carried out in an air-tight and heat-insulating test cabin. The self-insulation block is used to build a heat insulation wall, and the test cabin is divided into two equal spaces. The finishing layer (sealing layer) of the self-insulation block of the heat insulation wall is parallel to the wall surface, and the heat insulation wall and the inner wall of the test cabin are connected by industrial cement to ensure the air tightness of the whole. The cement coating thickness at each place is controlled to be 1.5 cm, and the partition area is 1.6 m x 2.0 m. The air in one space is continuously heated and warmed, and the temperature is controlled at 60 ℃ ± 1 ℃. The temperature of the detection area on the other side is detected after 6 h to test the actual heat insulation performance. In addition, an infrared temperature measurement camera is arranged in the detection area, and the infrared temperature measurement photograph of the heat insulation wall is taken after 3 h of the test;

[0064] Meanwhile, in the heat insulation performance test, the actual area of the brick surface on both sides of the heat insulation wall is measured and calculated when the heat insulation wall is built. The calculation method is: brick surface occupancy rate = (actual area of brick surface / 3.2 m 2 ) x 100%;

[0065] Performance detection of the self-insulation block:

[0066] It includes the conventional compressive strength detection and the sealing layer closed pore rate detection.

[0067] The detection and characterization results are shown in the following table:

[0068] Detection zone temperature Brick face occupancy Strength grade Closed layer closed cell ratio 23.7℃ 97.6％ MU10 ≥99.9％

[0069] Meanwhile, the infrared temperature measurement photograph is shown in Figure 1 . Figure 1It can be seen that there is no obvious heat radiation from the surface of the self-insulation block, which proves that the actual insulation effect of the self-insulation block is extremely excellent, and the heat radiation at the brick joint is also obviously controlled. In addition, from the brick surface occupancy rate, it can be seen that the cement has a more obvious penetration phenomenon into the self-insulation block, so that the actual occupancy rate of the brick surface is higher, and the actual block usage is also more than the conventional usage.

[0070] Comparative Example 1

[0071] The same detection and characterization as in Example 1 were performed on the commercially available void-type self-insulation block with the same size specification.

[0072] The characterization includes:

[0073] Wall performance test:

[0074] The self-insulation block was used as a test sample, and the thermal insulation performance test was carried out in an airtight and heat-insulating test cabin. The self-insulation block was used to build a thermal insulation wall, which divided the test cabin into two equal spaces. The self-insulation block of the thermal insulation wall was parallel to the wall surface, and the thermal insulation wall and the inner wall of the test cabin were connected with industrial cement to ensure the air tightness of the whole. The cement coating thickness at each place was controlled to be 1.5 cm, and the partition area was 1.6 m x 2.0 m. The air in one space was continuously heated to control the temperature at 60℃±1℃. The temperature of the detection area on the other side was detected after 6h to test the actual thermal insulation performance. In addition, an infrared temperature measurement camera was set in the detection area, and the thermal insulation wall was photographed by infrared temperature measurement after 3h of the test;

[0075] In the thermal insulation performance test, the actual occupancy area of the brick surface on both sides of the thermal insulation wall was measured and calculated when the thermal insulation wall was built. The calculation method was: brick surface occupancy rate = (actual occupancy area of brick surface / 3.2m 2 ) x 100%;

[0076] Self-insulation block performance test:

[0077] It includes the conventional compressive strength test and the closed pore rate test of the coating layer.

[0078] The test and characterization results are shown in the following table:

[0079]

[0080] At the same time, the infrared temperature measurement camera is shown in Figure 2 . Figure 2It can be obviously seen that there is slight heat radiation on the brick surface of the thermal insulation wall, which shows that a small amount of gas still interacts and directly passes through the self-insulation block for heat diffusion under the condition of incomplete closed pores. Meanwhile, the heat radiation at the brick joint is obviously stronger than the characterization result of Example 1, which shows that the existing commercially available pore type self-insulation block has obvious gap heat transfer, resulting in relatively limited thermal insulation performance when actually used for building thermal insulation walls. This conclusion can also be verified by the temperature of the detection area. And the brick surface occupancy rate is also much lower than Example 1, which shows that although the existing commercially available pore type self-insulation block has a rich pore structure, the actual cement penetration is poor, and the actual occupancy rate of the brick surface is low. Moreover, the strength grade of the commercially available pore type self-insulation block is obviously lower than the self-insulation block prepared by the present application.

[0081] Comparative Example 2

[0082] A self-insulation block is prepared by the following method:

[0083] 1) preparing a base material, the base material is composed of 9wt% foaming agent, 25wt% industrial clay, 5wt% rock wool, 45wt% coal gangue and the balance of water, wherein the foaming agent is composed of 30wt% calcium sulfate, 10wt% sodium oxide and 60wt% barium carbonate, and the base material is sintered at 1050℃ for 3.5h to obtain a rough blank with a size of 10.5cmx10.5cmx10.5cm, and the rough blank with poor appearance such as edge material shortage and poor surface flatness is selected, crushed and ground after crushing and grinding to pass through an 80 mesh sieve to obtain sand material;

[0084] 2) preparing a silicon modified material, the silicon modified material is composed of 25wt% sodium silicate, 28wt% dimethylsilanediol, 0.5wt% sodium formate, 1wt% 3,4,5,7-tetrahydroxyflavone and the balance of water, and the silicon modified material is mixed with the sand material at a mass ratio of 1:3 to form a closed material;

[0085] 3) coating the closed material prepared in step 2) on the opposite two surfaces of the rough blank prepared in step 1), and the coating amount is 180g / m 2 , and after high temperature sintering at 750℃ for 90min, a closed layer is formed to obtain a self-insulation block.

[0086] The performance of the self-insulation block is detected and characterized.

[0087] The characterization includes:

[0088] Wall performance test:

[0089] The self-insulation block prepared is used as a test sample to perform a heat insulation performance test in an air-tight and heat-insulation test cabin. The test cabin is divided into two equal spaces by a heat-insulation wall made of the self-insulation blocks. The surface of the self-insulation blocks of the heat-insulation wall is parallel to the wall surface, and the heat-insulation wall and the inner wall of the test cabin are connected by industrial cement to ensure the air-tightness of the whole. The thickness of the cement coating is controlled to be 1.5 cm, and the area of the partition is 1.6 m x 2.0 m. The air in one space is continuously heated to control the temperature at 60℃±1℃. The temperature of the other space is room temperature 20℃ at the beginning of the test, and the temperature of the test space is detected after 6 hours to test the actual heat-insulation performance. In addition, an infrared temperature measurement camera is arranged in the test space to take infrared temperature measurement photographs of the heat-insulation wall after 3 hours of the test.

[0090] Meanwhile, during the heat-insulation performance test, the actual area of the brick surface of the heat-insulation wall is measured and calculated when the heat-insulation wall is built. The calculation method is: brick surface occupancy rate=(actual area of brick surface / 3.2 m 2 ) x 100%.

[0091] Performance test of the self-insulation block:

[0092] The performance test includes the conventional compressive strength test and the closed pore rate test of the closed layer.

[0093] The test results are shown in the following table:

[0094] Detection zone temperature Brick face occupancy Strength grade Closed layer closed cell ratio 24.9℃ 93.2％ MU10 ≥99.9％

[0095] Meanwhile, the infrared temperature measurement photographs are shown in Figure 3 . It can be seen from Figure 3 that there is no obvious heat radiation on the brick surface of the self-insulation block, which is close to Example 1 and much better than Comparative Example 1. However, the heat radiation phenomenon at the brick joint is close to Comparative Example 1. From the data of the brick surface occupancy rate, it can be seen that the cement has poor permeability, which leads to obvious heat transfer at the brick joint, and the actual temperature of the test space is higher than that of Example 1. Therefore, the heat transfer at the brick joint is one of the heat transfer phenomena of the heat-insulation wall, and the actual heat-insulation effect of the self-insulation block can be effectively improved by inhibiting the heat transfer at the brick joint.

[0096] Example 2

[0097] A self-insulation block is prepared by the following method:

[0098] 1) Preparation of a base material, the base material is composed of 6wt% foaming agent, 22wt% industrial clay, 4wt% rock wool, 50wt% coal gangue and the balance of water, wherein the foaming agent is composed of 25wt% calcium sulfate, 5wt% sodium oxide and 70wt% barium carbonate, the base material is sintered at 1050°C for 3.5h to obtain a rough blank with a size of 10.5cmx10.5cmx10.5cm, and the rough blank with poor quality such as edge material shortage and poor surface flatness is selected, crushed and ground to pass through an 80 mesh sieve to obtain sand material;

[0099] 2) Preparation of a silicon modified material, the silicon modified material is composed of 20wt% sodium silicate, 25wt% dimethylsilanediol, 0.8wt% sodium formate, 0.8wt% 3,4,5,7-tetrahydroxyflavone and the balance of water, the silicon modified material is mixed with the sand material at a mass ratio of 1:2.8 and 1:1.3 to obtain a sealing material and a refining material;

[0100] 3) The sealing material prepared in step 2) is coated on the opposite two surfaces of the rough blank prepared in step 1), and the coating amount is 200g / m 2 , and after sintering at 750°C for 90min, a sealing layer is formed to obtain a rough block (i.e. a sealing layer is formed on the finishing layer), and the refining material prepared in step 2) is coated on the four surfaces of the rough block which are not the sealing layer, and the coating amount is 220g / m 2 , and after sintering at 300°C under a low pressure of 0.3atm for 45min, a functional surface layer is formed to obtain a self-insulation block.

[0101] The self-insulation block is subjected to performance detection and characterization.

[0102] The characterization includes:

[0103] Wall performance test:

[0104] The self-insulation block prepared is used as a test sample, and a heat insulation performance test is carried out in an air-tight and heat-insulating test cabin. The self-insulation block is used to build a heat insulation wall, and the test cabin is divided into two equal spaces, the finishing layer (sealing layer) of the self-insulation block of the heat insulation wall is parallel to the wall surface, and the heat insulation wall and the inner wall of the test cabin are connected with industrial cement to ensure the air tightness of the whole, the cement coating thickness of each place is controlled at 1.5cm, and the partition area is 1.6m x 2.0m. In one space, the air is continuously heated to control the temperature at 60°C±1°C, and the temperature of the detection area on the other side is detected after 6h to test the actual heat insulation performance. In addition, an infrared temperature measurement camera is arranged in the detection area, and the infrared temperature measurement photograph of the heat insulation wall is taken after 3h of the test;

[0105] At the same time, in the heat insulation performance test, the actual area of the two brick surfaces of the heat insulation wall is measured and calculated when the heat insulation wall is built. The calculation method is: brick surface occupancy rate = (actual area of brick surface / 3.2m 2 ) × 100%;

[0106] Self-insulation block performance detection:

[0107] Including the conventional compressive strength detection and closed layer closed pore rate detection.

[0108] The detection characterization results are shown in the following table:

[0109] Detection zone temperature Brick face occupancy Strength grade Closed layer closed cell ratio 24.0℃ 97.1％ MU10 ≥99.9％

[0110] The infrared temperature measurement phase diagram is similar to the characterization results of Example 1, and will not be shown here. From the characterization results, the self-insulation block of this example also shows good heat insulation performance and mechanical properties close to Example 1.

[0111] Example 3

[0112] A self-insulation block is prepared by the following method:

[0113] 1) Prepare the base material, which is composed of 12wt% foaming agent, 28wt% industrial clay, 8wt% rock wool, 45wt% coal gangue and the balance of water, wherein the foaming agent is composed of 35wt% calcium sulfate, 15wt% sodium oxide and 50wt% barium carbonate. The base material is sintered at 1050℃ for 3.5h to form a rough blank with a size of 10.5cm×10.5cm×10.5cm. Select rough blanks with poor phase, such as edge and corner material shortage, poor surface flatness, crush and grind after selection, and pass through an 80 mesh sieve to obtain sand material;

[0114] 2) Prepare the silicon modified material, which is composed of 28wt% sodium silicate, 32wt% dimethylsilanediol, 0.8wt% sodium formate, 0.5wt% 3,4,5,7-tetrahydroxyflavone and the balance of water. Mix the silicon modified material and the sand material at a mass ratio of 1:3.2 and 1:1.7 to form a sealing material and a refining material;

[0115] 3) Apply the sealing material prepared in step 2) to the opposite two surfaces of the rough blank prepared in step 1), with a coating amount of 150g / m 2 , and after sintering at 750℃ for 90min, a sealing layer is formed to obtain a rough block (i.e. a sealing layer is formed on the finishing layer), and the refining material prepared in step 2) is coated on the four sides of the rough block which is not a sealing layer, with a coating amount of 180g / m 2 , and after sintering at 280℃ under a low pressure of 0.3atm for 60min, a functional surface layer is formed to obtain a self-insulation block.

[0116] The self-insulation block is subjected to performance detection and characterization.

[0117] The characterization includes:

[0118] Wall performance test:

[0119] The self-insulation block is subjected to performance detection and characterization.

[0120] In the heat insulation performance test, the actual area of the brick surface on both sides of the heat insulation wall is measured and calculated when the heat insulation wall is built. The calculation method is: brick surface occupancy rate = (actual area of brick surface / 3.2m 2 )×100%;

[0121] Self-insulation block performance detection:

[0122] It includes routine compressive strength detection and closed layer closed pore rate detection.

[0123] The detection and characterization results are shown in the following table:

[0124] Detection zone temperature Brick face occupancy Strength grade Closed layer closed cell ratio 23.6℃ 97.0％ MU10 ≥99.9％

[0125] The infrared temperature measurement phase diagram is similar to the characterization results of Example 1 and is not shown here. From the characterization results, the self-insulation block of this example also shows good heat insulation performance and mechanical properties close to Example 1.

[0126] Comparative Example 3

[0127] The commercially available organic filling type self-insulation block with the same size specification is subjected to the same detection and characterization as Example 1.

[0128] The characterization includes:

[0129] Wall performance test:

[0130] The self-insulation block is taken as a test sample to conduct the heat insulation performance test in an air-tight and heat-insulation test cabin. The test cabin is divided into two equal spaces by the self-insulation block wall. The self-insulation block of the self-insulation wall is coated with a layer (closed layer) parallel to the wall surface, and the self-insulation wall and the inner wall of the test cabin are connected by industrial cement to ensure the air tightness of the whole. The thickness of the cement coating at each place is controlled to be 1.5 cm, and the partition area is 1.6 m x 2.0 m. The air in one space is continuously heated to control the temperature at 60℃±1℃. The temperature of the detection area on the other side is detected after 6h to test the actual heat insulation performance. In addition, an infrared temperature measurement camera is arranged in the detection area, and the infrared temperature measurement photograph of the self-insulation wall is taken after 3h of the test.

[0131] Meanwhile, in the heat insulation performance test, the actual area of the brick surface on both sides of the self-insulation wall is measured and calculated when the self-insulation wall is built. The calculation method is: brick surface occupancy rate = (actual area of brick surface / 3.2m 2 ) x 100%;

[0132] Performance test of self-insulation block:

[0133] including the conventional compressive strength test and the closed pore rate test of the coating layer.

[0134] The test results are shown in the following table:

[0135] Detection zone temperature Brick face occupancy Strength grade Closed layer closed cell ratio 27.1℃ 92.6％ MU7 100％

[0136] The infrared temperature measurement photograph is similar to the characterization results of Comparative Example 2, and will not be shown here. According to the characterization results, the commercially available organic filled self-insulation block is indeed slightly better than the commercially available pore type self-insulation block in terms of heat insulation performance, and the strength grade is also relatively high.

[0137] However, on this basis, the self-insulation block prepared in Example 1, the self-insulation block of Comparative Example 1 and the self-insulation block of this example are tested for thermal shock resistance.

[0138] The built self-insulation wall is heated to 60℃ for 1h, then cooled to ≤20℃ by water flushing within 2min, and the above-mentioned wall performance test is repeated after 30 times of repeated cooling. The temperature of the detection area is detected.

[0139] The detection result shows that the temperature of the detection area of the heat insulation wall made of the self-heat preservation building blocks of example 1 is 23.9 DEG C after the heat shock test, which is basically the same as that of example 1, the temperature of the detection area of the heat insulation wall made of the self-heat preservation building blocks of comparative example 1 is 29.8 DEG C after the heat shock test, which is slightly higher than that of comparative example 1, and the researchers find that the performance of the self-heat preservation building blocks is decreased due to the surface scouring of water, and the structural stability of the self-heat preservation building blocks is relatively good. The temperature of the detection area of the heat insulation wall made of the self-heat preservation building blocks of comparative example 3 is 30.6 DEG C after the heat shock test, which is far lower than the heat insulation performance before the heat shock, and a small amount of solid matter falls off and micro cracks appear on the wall surface. It is shown that the existing organic filling type self-heat preservation building blocks generally have the problem of relatively poor heat shock resistance and aging resistance, and the problem is effectively solved by the self-heat preservation building blocks.

[0140] Comparative example 4

[0141] A self-heat preservation building block is prepared by the following method:

[0142] 1) A base material is prepared, the base material is composed of 9wt% foaming agent, 25wt% industrial clay, 5wt% rock wool, 45wt% coal gangue and the balance of water, wherein the foaming agent is composed of 30wt% calcium sulfate, 10wt% sodium oxide and 60wt% barium carbonate, the base material is sintered at 1050 DEG C for 3.5h to obtain a coarse blank with a size of 10.5cm*10.5cm*10.5cm, and the coarse blank with poor appearance, such as edge and corner material shortage and poor surface flatness, is selected, crushed and ground, and then sieved through an 80 mesh sieve to obtain sand material;

[0143] 2) A silicon modified material is prepared, the silicon modified material is composed of 25wt% sodium silicate, 28wt% dimethylsilanediol, 0.5wt% sodium formate, 1wt% 3,4,5,7-tetrahydroxyflavone and the balance of water, the silicon modified material and the sand material are mixed in a mass ratio of 1:3 and 1:1.5 respectively to form a sealing material and a refining material;

[0144] 3) The sealing material prepared in step 2) is coated on the opposite two surfaces of the coarse blank prepared in step 1), the coating amount is 180g / m 2 , and after sintering at 750 DEG C for 90min, a sealing layer is formed to obtain a coarse building block (i.e. a sealing layer is formed on the finishing layer), the refining material prepared in step 2) is coated on the four surfaces of the coarse building block which is not the sealing layer, the coating amount is 200g / m 2 , and after sintering at 350 DEG C under the condition of 0.3atm low pressure for 45min, a functional surface layer is formed to obtain a self-heat preservation building block.

[0145] The performance of the self-heat preservation building block is detected and characterized.

[0146] The characterization includes:

[0147] Wall performance test:

[0148] The self-insulation block prepared is used as a test sample to perform a heat insulation performance test in an air-tight and heat-insulation test cabin. The test cabin is divided into two equal spaces by a heat-insulation wall made of the self-insulation blocks. The self-insulation blocks of the heat-insulation wall are coated with a coating layer (closed layer) parallel to the wall surface, and the heat-insulation wall and the inner wall of the test cabin are connected by industrial cement to ensure the air tightness of the whole. The thickness of the cement coating is controlled to be 1.5 cm, and the area of the partition is 1.6 m x 2.0 m. The air in one space is continuously heated to control the temperature at 60℃±1℃, and the temperature of the detection area on the other side is detected after 6 hours to test the actual heat-insulation performance.

[0149] Meanwhile, in the heat-insulation performance test, the actual area of the brick surface of the heat-insulation wall is measured and calculated when the heat-insulation wall is built. The calculation method is: brick surface occupancy rate = (actual area of brick surface / 3.2m 2 ) x 100%.

[0150] Performance detection of the self-insulation block:

[0151] including the conventional compressive strength detection and the closed layer closed pore rate detection.

[0152] The detection characterization results are shown in the following table:

[0153]

[0154]

[0155] From the above characterization results, it can be seen that the use of too high sintering temperature during the sintering of the fine material will increase the shrinkage rate of the cement-coated surface of the block, reduce the porosity, and weaken the permeability of the cement. The heat-insulation performance of the actual wall after being built is decreased.

Claims

1. A method for preparing a self-insulating building block, characterized in that: The method comprises: 1) Prepare the base material and sinter it into rough blank and sand material; 2) Prepare silicon modified material, mix the silicon modified material with sand material at a mass ratio of 1: (2.8-3.2) and 1: (1.3-1.7) to form sealing material and refining material; 3) coating the sealing material prepared in step 2) on two opposite sides of the rough block prepared in step 1), sintering at high temperature to form a sealing layer to obtain a rough building block, coating the refined material prepared in step 2) on four sides of the non-sealing layer of the rough building block, sintering at low temperature to form a functionalized surface layer to obtain a self-insulating building block; Step 2) The silicon modified material comprises 20-28 wt% silicate, 25-32 wt% organosilicon, 0.3-0.8 wt% coagulant, 0.5-1 wt% antioxidant, and the balance is water; Step 3) When the sealing material is applied on two opposite sides of the rough blank, the coating amount is 150-200 g / m 2 ; Step 3) When applying the refined material obtained in step 2), the coating amount is 180-220 g / m 2 ; Step 3) the high temperature sintering is controlled at 600-800°C and low pressure sintering is performed for 60-120 minutes; The low-pressure sintering is carried out under the condition of ambient pressure ≤ 0.3 atm; Step 3) The low-temperature sintering is controlled at 200-300° C. for 45-75 minutes.

2. The method for preparing a self-insulating building block according to claim 1, wherein: Step 1) The base material is composed of 6-12 wt% foaming agent, 22-28 wt% clay, 4-8 wt% mineral wool, 30-50 wt% slag and the balance water; Step 1) The sintering is carried out at 950-1100° C. for 3-5 hours.

3. The method for preparing a self-insulating building block according to claim 2, wherein: The foaming agent is composed of 25-35 wt% calcium sulfate, 5-15 wt% sodium oxide and the balance barium carbonate; The mineral wool is slag wool and / or rock wool and / or glass wool and / or aluminum silicate refractory fiber; The slag is perlite and / or shale and / or pyroclastic rock and / or coal gangue.

4. The method for preparing a self-insulating building block according to claim 1, wherein: The organosilicon is dimethylsilanediol; The coagulant is sodium formate; The antioxidant is 3,4,5,7-tetrahydroxyflavone.

5. A self-insulating building block produced by the method according to any one of claims 1 to 4.

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