Self-heating rubber elastic particles, preparation method and application thereof, and bonding mortar

Abstract

The present invention relates to the technical field of building materials, and discloses a self-heating rubber elastic particle, a preparation method and application thereof, and a bonding mortar. The self-heating rubber elastic particle comprises a self-heating material and a rubber film wrapping the self-heating material; wherein the material of the rubber film is vinyl acetate-ethylene copolymer. The self-heating rubber elastic particle is obtained by making a rubber film from a material emulsion for preparing the rubber film, and wrapping the self-heating material to form closed particles. The self-heating rubber elastic particle provided by the present invention can generate continuous heat under the action of water and the heat lasts for a long time, so that the bonding mortar constructed under negative temperature in winter can be normally hydrated and hardened at medium and high temperatures.

Description

Technical Field

[0001] The invention relates to the technical field of building materials, and in particular to self-heating rubber elastic particles, a preparation method and application thereof, and bonding mortar. Background Art

[0002] Energy conservation and emission reduction have further strengthened the requirements for building energy conservation, and external wall insulation projects have become a very important part of construction projects. In the construction of external wall insulation projects, due to the construction period or other reasons, it is necessary to construct in negative temperatures in winter. However, for most northern regions, low temperatures will cause the mortar to freeze after adding water, making it impossible to construct. Even if it is constructed, it will fall off quickly and fail to meet the construction requirements. If construction is forced to be carried out in a negative temperature environment in winter, after a freeze-thaw cycle, frost heave damage will occur, and the mortar products will have low strength, cracking, alkali whitening, etc. In severe cases, they will fall off from the base. Therefore, northern regions generally do not construct in a negative temperature environment in winter.

[0003] The practice for construction in winter under negative temperatures is generally to add different types and quantities of antifreeze components to concrete, add hot water when mixing, and add plastic film covering, straw mat covering, baking and other maintenance measures to avoid freezing damage. In terms of external wall insulation projects, winter construction is generally not recommended. Even if antifreeze components are added, the frost resistance is relatively poor due to the thin thickness and small volume during construction.

[0004] Many patent documents also have related research. For example, Chinese invention patent CN201410352989.2 discloses an antifreeze bonding mortar, which can be used in the extreme winter negative temperature environment of -20℃ to -30℃ through the combination of multiple component raw materials and antifreeze agent and has good mechanical properties; Chinese invention patent CN201810318303.6 discloses a two-component negative temperature fast repair mortar and its preparation and use method, which can achieve the purpose of rapid construction and antifreeze in winter negative temperature by mixing two-component A powder and B antifreeze liquid; Chinese invention patent CN201710120414.1 discloses a high-strength antifreeze two-component mortar additive and its preparation method, which obtains the antifreeze type mortar additive in winter negative temperature environment by reasonable proportioning of each component raw material of antifreeze agent and plastic stabilizer, and improves the comprehensive performance of traditional mortar in winter negative temperature environment.

[0005] The prior art usually adopts a two-component method, which causes many inconveniences in the actual construction process. In addition, the prior art basically adopts a method of adding an antifreeze component to the mortar.

[0006] The invention aims to provide a bonding mortar which can be used at negative temperature in winter without adding antifreeze components. Summary of the invention

[0007] The purpose of the present invention is to overcome the problems existing in the prior art and to provide a self-heating rubber elastic particle and a preparation method and application thereof, and a bonding mortar.

[0008] In order to achieve the above-mentioned object, the present invention provides a self-heating rubber elastic particle in a first aspect, wherein the particle comprises a self-heating material and a rubber film wrapping the self-heating material;

[0009] Wherein, the material of the adhesive film is vinyl acetate-ethylene copolymer.

[0010] The second aspect of the present invention provides a method for preparing the self-heating rubber elastic particles described in the first aspect, the method comprising: preparing a rubber film from a material emulsion for preparing a rubber film, and wrapping the self-heating material to form closed particles to obtain the self-heating rubber elastic particles.

[0011] The third aspect of the present invention provides the use of the self-heating rubber elastic particles described in the first aspect in the preparation of bonding mortar.

[0012] A fourth aspect of the present invention provides a bonding mortar comprising the self-heating rubber elastic particles described in the first aspect.

[0013] Through the above technical solution, the beneficial technical effects achieved by the present invention are as follows:

[0014] (1) The self-heating rubber elastic particles provided by the present invention can generate continuous heat under the action of water and the heat lasts for a long time, so that the bonding mortar constructed under negative temperatures in winter can be normally hydrated and hardened at medium and high temperatures.

[0015] (2) The bonding mortar made of the self-heating rubber elastic particles provided by the present invention can be used and constructed in a negative temperature environment in winter without the use of antifreeze, and its strength is not affected and no freeze-thaw damage will occur.

[0016] (3) After the bonding mortar provided by the present invention is mixed with water and stirred, when it is constructed under negative temperatures in winter, the slurry temperature can reach 5-40°C after compensating for the loss under negative temperatures in winter, which fully meets the construction temperature requirements for the hydration and hardening of the bonding mortar; at the same time, by adding self-heating rubber elastic particles, the mortar can further release heat for a long time, and the heat duration can reach 10-15 hours, so that the bonding mortar can completely set and gradually improve its own strength without causing frost heave damage. DETAILED DESCRIPTION

[0017] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0018] A first aspect of the present invention provides a self-heating rubber elastic particle, the particle comprising a self-heating material and a rubber film wrapping the self-heating material;

[0019] Wherein, the material of the adhesive film is vinyl acetate-ethylene copolymer.

[0020] The self-heating elastic adhesive particles provided by the present invention can be applied to bonding mortar. When constructing external wall insulation adhesive panels under negative temperatures in winter, the product construction and maintenance problems under negative temperatures in winter are not solved by antifreeze agents, hot water, and antifreeze measures such as covering with plastic films. Instead, the heat continuously provided by the self-heating viscoelastic particles is used to compensate for the temperature of the material itself and maintain the slurry temperature within a range of not less than 5°C. The construction is simple, more economical, and the project quality and safety are more guaranteed.

[0021] In some embodiments of the present invention, the solid content of the vinyl acetate-ethylene copolymer is not less than 50%.

[0022] In some embodiments of the present invention, the thickness of the adhesive film is 0.1-2 mm, preferably 0.3-1.5 mm. In the present invention, if the thickness of the adhesive film is too small, it is easy to be damaged, resulting in too fast heat release when it comes into contact with water, and it is unable to provide sufficient high-temperature curing for the mortar; if the thickness of the adhesive film is too large, it will not melt when it comes into contact with water, resulting in the self-heating particles being unable to provide sufficient curing temperature in the initial stage of slurry mixing, resulting in frost heave damage.

[0023] In some embodiments of the present invention, the self-heating material includes the following components in parts by weight: 15-35 parts of aluminum powder, 20-22 parts of calcium oxide, 17-23 parts of iron powder, 3-12 parts of sodium chloride, 5-15 parts of diatomaceous earth, 5-20 parts of sodium bicarbonate and 5-20 parts of activated carbon powder.

[0024] In some embodiments of the present invention, the average particle size of the particles is 1-10 mm, preferably 2-5 mm.

[0025] The second aspect of the present invention provides a method for preparing the self-heating rubber elastic particles described in the first aspect, the method comprising: preparing a rubber film from a material emulsion for preparing a rubber film, and wrapping the self-heating material to form closed particles to obtain the self-heating rubber elastic particles.

[0026] The third aspect of the present invention provides the use of the self-heating rubber elastic particles described in the first aspect in the preparation of bonding mortar.

[0027] The fourth aspect of the present invention provides a bonding mortar comprising the self-heating rubber elastic particles described in the first aspect. The bonding mortar is suitable for construction under negative temperature conditions in winter, especially when thin coating is applied, the heat lost instantly is replenished in time and continuously released to maintain normal cement hydration and hardening, meeting the needs of safe construction under negative temperature in winter, and no anti-freeze protection measures such as covering with plastic film, straw curtains, etc. are required under negative temperature in winter.

[0028] In some embodiments of the present invention, the bonding mortar includes the following raw materials in parts by weight: 35-55 parts of silicate cement, 45-65 parts of washed river sand, 3-5 parts of fly ash, 2-3 parts of heavy calcium powder, 2-5 parts of redispersible latex powder, 0.13-0.25 parts of cellulose ether HPMC, 0.2-0.4 parts of wood fiber, 0.2-0.4 parts of water repellent, 0.02-0.05 parts of starch ether, 2-6 parts of quicklime powder and 5-15 parts of self-heating rubber elastic particles.

[0029] In the present invention, the raw materials in the bonding mortar can be preferably selected as follows:

[0030] The silicate cement is P.O42.5 cement.

[0031] The average particle size of the washed river sand is 40-70 meshes.

[0032] The fly ash is Class 1 ash.

[0033] The average particle size of the heavy calcium powder is 200 meshes.

[0034] The viscosity of the cellulose ether HPMC is 75000-100000 mPa·s (20° C.).

[0035] The redispersible latex powder is a vinyl acetate-ethylene copolymer with an ash content of 10±2% and a glass transition point of -15±5°C.

[0036] The water repellent is silane-based water repellent powder.

[0037] The starch ether is hydroxypropyl starch ether.

[0038] The average particle size of the quicklime powder is 100-325 meshes.

[0039] Before use, stir the above bonding mortar with water, and the rubber elastic particles therein are gradually dissolved by water. The rubber elastic particles with a film thickness of 0.3mm will release self-heating materials after 120 minutes of dissolution. The calcium oxide in it releases heat rapidly when added with water, and the iron powder and aluminum powder in it can release heat by reacting with oxygen, or form a "galvanic cell" effect with activated carbon, water, sodium chloride, and sodium bicarbonate, and release heat through redox reactions to achieve continuous heating. The heat release lasts for 2-3 hours. All self-heating rubber elastic particles of different particle sizes are completely released, and the heat can last for 10-15 hours, so that the bonding mortar is completely finalized and its own strength is gradually improved.

[0040] The bonding mortar described in the present invention can solve the problems of freezing and poor hydration activity caused by negative temperatures in winter. The slurry temperature ranges from 20 to 80°C after adding water. When construction is carried out under negative temperatures in winter, after compensating for the losses under negative temperatures in winter, the slurry temperature can also reach 5 to 40°C, which fully meets the construction temperature requirements for hydration and hardening of the bonding mortar.

[0041] The present invention does not need to add antifreeze agents of different antifreeze grades, and normal construction can be achieved under negative temperatures in winter, so the construction is simpler and more economical; the bonding mortar of the present invention can achieve continuous heating after adding water, and there is no need to add antifreeze measures such as plastic film, straw curtains, baking, etc. under negative temperatures in winter, so the construction is simplified, the cost is lower, and it is easier to manage; the present invention uses quicklime and self-heating rubber bullet particles at the same time, and the quicklime and water release heat, the iron powder and aluminum powder and oxygen reduction reaction release heat, and the iron powder and aluminum powder and activated carbon, salt, and water form a primary battery to release heat, and the three aspects of continuous heat release are used to compensate for the heat loss under negative temperatures in winter and the heat required for the normal operation of the product.

[0042] The present invention will be described in detail below through examples.

[0043] In the following examples and comparative examples, if no specific conditions are specified, the experiments were carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used, if no manufacturer is specified, are all conventional products that can be obtained through commercial channels.

[0044] Sources:

[0045] Vinyl acetate-ethylene copolymer: product number is P101486-250g;

[0046] HPMC: Product number is H108825-500g.

[0047] Preparation Example 1

[0048] This example is used to illustrate the preparation of self-heating rubber elastic particles.

[0049] (1) preparing a self-heating material, wherein the self-heating material comprises the following components in parts by weight: 15 parts of aluminum powder, 22 parts of calcium oxide, 17 parts of iron powder, 12 parts of sodium chloride, 15 parts of diatomaceous earth, 5 parts of sodium bicarbonate and 20 parts of activated carbon powder, and mixing them uniformly;

[0050] (2) preparing a vinyl acetate-ethylene copolymer emulsion;

[0051] (3) The emulsion obtained in step (2) is made into a film, and the self-heating material obtained in step (1) is wrapped to form closed particles, thereby obtaining the self-heating rubber elastic particles; the average particle size of the self-heating rubber elastic particles is 2 mm, and the thickness of the film is 0.3 mm.

[0052] Preparation Example 2

[0053] This example is used to illustrate the preparation of self-heating rubber elastic particles.

[0054] (1) preparing a self-heating material, wherein the self-heating material comprises the following components in parts by weight: 35 parts of aluminum powder, 20 parts of calcium oxide, 23 parts of iron powder, 3 parts of sodium chloride, 5 parts of diatomaceous earth, 20 parts of sodium bicarbonate and 5 parts of activated carbon powder, and mixing them uniformly;

[0055] (2) preparing a vinyl acetate-ethylene copolymer emulsion;

[0056] (3) The emulsion obtained in step (2) is made into a film, and the self-heating material obtained in step (1) is wrapped to form closed particles, thereby obtaining the self-heating rubber elastic particles; the average particle size of the self-heating rubber elastic particles is 5 mm, and the thickness of the film is 1.5 mm.

[0057] Preparation Example 3

[0058] This example is used to illustrate the preparation of self-heating rubber elastic particles.

[0059] (1) preparing a self-heating material, wherein the self-heating material comprises the following components in parts by weight: 30 parts of aluminum powder, 21 parts of calcium oxide, 20 parts of iron powder, 8 parts of sodium chloride, 10 parts of diatomaceous earth, 15 parts of sodium bicarbonate and 12 parts of activated carbon powder, and mixing them uniformly;

[0060] (2) preparing a vinyl acetate-ethylene copolymer emulsion;

[0061] (3) The emulsion obtained in step (2) is made into a film, and the self-heating material obtained in step (1) is wrapped to form closed particles, thereby obtaining the self-heating rubber elastic particles; the average particle size of the self-heating rubber elastic particles is 4 mm, and the thickness of the film is 1 mm.

[0062] Example 1

[0063] This example is used to illustrate the preparation of bonding mortar.

[0064] The following raw materials in parts by weight are mixed evenly to obtain bonding mortar 1#.

[0065] The formula is as follows: 35 parts of silicate cement, 65 parts of washed river sand, 3 parts of fly ash, 2 parts of heavy calcium powder, 2 parts of redispersible latex powder, 0.25 parts of HPMC, 0.4 parts of wood fiber, 0.4 parts of water repellent, 0.05 parts of starch ether, 6 parts of quicklime powder, and 15 parts of self-heating rubber elastic particles.

[0066] The self-heating rubber elastic particles are prepared in Preparation Example 1.

[0067] Example 2

[0068] This example is used to illustrate the preparation of bonding mortar.

[0069] The following raw materials in parts by weight are mixed evenly to obtain bonding mortar 2#.

[0070] The formula is as follows: 45 parts of silicate cement, 55 parts of washed river sand, 4 parts of fly ash, 2 parts of heavy calcium powder, 3 parts of redispersible latex powder, 0.2 parts of HPMC, 0.3 parts of wood fiber, 0.3 parts of water repellent, 0.04 parts of starch ether, 4 parts of quicklime powder, and 10 parts of self-heating rubber elastic particles.

[0071] The self-heating rubber elastic particles are prepared in Preparation Example 2.

[0072] Example 3

[0073] This example is used to illustrate the preparation of bonding mortar.

[0074] The following raw materials in parts by weight are mixed evenly to obtain bonding mortar 3#.

[0075] The formula is as follows: 55 parts of silicate cement, 45 parts of washed river sand, 5 parts of fly ash, 3 parts of heavy calcium powder, 2 parts of redispersible latex powder, 0.16 parts of HPMC, 0.2 parts of wood fiber, 0.2 parts of water repellent, 0.03 parts of starch ether, 2 parts of quicklime powder, and 5 parts of self-heating rubber elastic particles.

[0076] The self-heating rubber elastic particles are prepared in Preparation Example 3.

[0077] Example 4

[0078] This example is used to illustrate the preparation of bonding mortar.

[0079] The following raw materials in parts by weight are mixed evenly to obtain bonding mortar 4#.

[0080] The formula is as follows: 65 parts of silicate cement, 35 parts of washed river sand, 6 parts of fly ash, 3 parts of heavy calcium powder, 5 parts of redispersible latex powder, 0.13 parts of HPMC, 0.1 parts of wood fiber, 0.1 parts of water repellent, 0.02 parts of starch ether, 1 part of quicklime powder, and 1 part of self-heating rubber elastic particles.

[0081] The self-heating rubber elastic particles are prepared in Preparation Example 3.

[0082] Test Case

[0083] The pull-out strength of the bonding mortars prepared in Examples 1-4 at different negative temperatures was tested respectively.

[0084] The specific determination method is:

[0085] The test and data analysis were carried out according to the tensile bond strength test method in Chapter 6.4 of GB / T29906-2013 "Molded polystyrene board thin plaster exterior wall insulation system materials". Forming, curing and testing were carried out at the corresponding -5℃, -10℃ and -15℃ respectively.

[0086] The test results are shown in Table 1-3.

[0087] Table 1 -5℃ tensile strength of each example

[0088] Age Bonding mortar 1# Bonding mortar 2# Bonding mortar 3# Bonding mortar 4# 3d 0.08MPa 0.06MPa 0.05MPa 0.06MPa 7d 0.09MPa 0.07MPa 0.06MP 0.08MPa 14d 0.15MPa 0.14MPa 0.12MP 0.07MPa 28d 0.18MPa 0.16MPa 0.15MPa 0.09MPa

[0089] Table 2 -10℃ tensile strength of each example

[0090] Age Bonding mortar 1# Bonding mortar 2# Bonding mortar 3# Bonding mortar 4# 3d 0.07MPa 0.06MPa 0.04MPa 0.05MPa 7d 0.08MPa 0.06MPa 0.05MP 0.07MPa 14d 0.14MPa 0.13MPa 0.11MP 0.07MPa 28d 0.17MPa 0.15MPa 0.12MPa 0.08MPa

[0091] Table 3 -15℃ tensile strength of each example

[0092] Age Bonding mortar 4# Bonding mortar 4# Bonding mortar 4# Bonding mortar 4# 3d 0.05MPa 0.05MPa 0.04MPa 0.05MPa 7d 0.07MPa 0.06MPa 0.04MP 0.06MPa 14d 0.12MPa 0.11MPa 0.10MP 0.06MPa 28d 0.15MPa 0.13MPa 0.11MPa 0.07MPa

[0093] It can be seen from the results in Tables 1-3 that the bonding mortar prepared using the self-heating rubber elastic particles of the present invention can maintain high tensile strength for a long time at -5°C, -10°C, and -15°C.

[0094] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A self-heating rubber elastic particle, characterized in that: The particles include a self-heating material and a film wrapping the self-heating material; Wherein, the material of the adhesive film is vinyl acetate-ethylene copolymer.

2. The self-heating rubber elastic particles according to claim 1, wherein: The solid content of the vinyl acetate-ethylene copolymer is not less than 50%.

3. The self-heating rubber elastic particles according to claim 1 or 2, wherein: The thickness of the adhesive film is 0.1-2 mm.

4. The self-heating rubber elastic particles according to claim 3, wherein: The thickness of the adhesive film is 0.3-1.5 mm.

5. The self-heating rubber elastic particles according to any one of claims 1 to 4, wherein: The self-heating material comprises the following components in parts by weight: 15-35 parts of aluminum powder, 20-22 parts of calcium oxide, 17-23 parts of iron powder, 3-12 parts of sodium chloride, 5-15 parts of diatomaceous earth, 5-20 parts of sodium bicarbonate and 5-20 parts of activated carbon powder.

6. The self-heating rubber elastic particles according to any one of claims 1 to 5, wherein: The average particle size of the particles is 1-10 mm, preferably 2-5 mm.

7. A method for preparing the self-heating rubber elastic particles according to any one of claims 1 to 6, characterized in that: The method comprises: preparing a film from a material emulsion for preparing the film, and wrapping the self-heating material to form closed particles to obtain the self-heating rubber elastic particles.

8. Use of the self-heating rubber elastic particles according to any one of claims 1 to 6 in preparing bonding mortar.

9. A bonding mortar comprising the self-heating rubber elastic particles according to any one of claims 1 to 6.

10. The bonding mortar according to claim 9, wherein: The bonding mortar comprises the following raw materials in parts by weight: 35-55 parts of silicate cement, 45-65 parts of washed river sand, 3-5 parts of fly ash, 2-3 parts of heavy calcium powder, 2-5 parts of redispersible latex powder, 0.13-0.25 parts of cellulose ether HPMC, 0.2-0.4 parts of wood fiber, 0.2-0.4 parts of water repellent, 0.02-0.05 parts of starch ether, 2-6 parts of quicklime powder and 5-15 parts of self-heating rubber elastic particles.