Inorganic material foaming foam stabilizer suitable for high-altitude air pressure environment and preparation method of inorganic material foaming foam stabilizer

Abstract

The invention belongs to the field of building materials. The invention provides an inorganic material foaming foam stabilizer suitable for a high-altitude air pressure environment and a preparation method thereof, the foam stabilizer comprises a foam stabilizing copolymer, cellulose ether, polyacrylamide, bentonite and deionized water, and the foam stabilizing copolymer is formed by copolymerization of dimethyl silicone oil, dimethyl disiloxane and a polydimethylsiloxane cross-linked polymer. The inorganic material foaming foam stabilizer is used for foaming inorganic materials, contributes to improving the strength of a bubble wall, increasing the viscosity of a bubble film and enabling foams to be uniform and tough, remarkably improves the foam stabilizing performance of a product foaming bubble body under high-altitude and low-air-pressure conditions, can be used in a normal-pressure environment and can also meet the foam stabilizing requirement under the high-altitude and low-air-pressure environment.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of building materials, and particularly relates to a foaming stabilizer for inorganic foaming materials suitable for high-altitude pressure environment and a preparation method thereof. BACKGROUND

[0002] The foaming stabilizer is a kind of surfactant capable of prolonging and stabilizing the foam to keep long-term performance. Its main function is to reduce the surface tension of the slurry liquid phase, thereby stabilizing the gas bubbles and ensuring the overall formation of fine and uniform porous structure of the foaming material, so as to improve the performance of the foaming material. That is, the foaming stabilizer can improve the stability of the gas bubbles, prolong the half-life period of the foam, and ensure the stable structure of the foaming material during the curing process. The foaming stabilizer is widely used in the fields of concrete, magnesite, gypsum, urea-formaldehyde resin, etc.

[0003] In the foamed concrete, the use of the foaming stabilizer can significantly improve the physical properties of the concrete, increase the strength, thermal insulation performance and durability. However, in the high-altitude area, the low-altitude environment will affect the stability of the gas bubbles due to the influence of geographical location and altitude. In the foaming process, large bubbles are easily broken, the spacing coefficient of the gas bubbles in the foaming material increases, the pore structure deteriorates obviously, the large bubbles become larger and larger until they break, the average pore diameter of the gas bubble system increases, and the instability speed of the gas bubble system is accelerated, which will affect the structural stability of the foaming product. This result has guiding significance for the instability mechanism of the gas bubbles in the low-altitude environment at high altitudes and the development of the corresponding foaming technology.

[0004] At present, the commonly used foaming stabilizers in China mainly include macromolecular substances (such as polyacrylamide, starch and cellulose, etc.), modified polyether emulsion and animal protein. The macromolecular substances realize the stabilization by increasing the viscosity of the foaming liquid, but the effect is not obvious and the foaming multiple is reduced; the modified polyether emulsion has obvious stabilization effect, but its own stability is greatly affected by the external temperature, especially when the temperature is too high (> 50℃), the demulsification phenomenon will occur; the animal protein has good stabilization effect and has been recognized at home and abroad, but its cost is high and the shelf life is short, which limits its wide application.

[0005] However, the above-mentioned foaming stabilizers are mainly used in normal pressure environment and do not consider the foaming demand in the low-altitude environment at high altitudes.

[0006] Therefore, the present application aims to develop a new foaming stabilizer with low sensitivity and high stability suitable for use in the foaming material in the low-altitude environment at high altitudes, to effectively improve the performance of the foaming material and to meet the market demand. SUMMARY

[0007] To solve the problems in the prior art, the present application provides an inorganic material foaming stabilizing agent suitable for high-altitude air pressure environment and a preparation method thereof, which significantly improves the stability of inorganic foaming material bubbles, significantly improves the bubble wall strength, increases the bubble film viscosity, makes the foam uniform and tough, and meets the stability requirements of foaming materials under high-altitude low-pressure conditions.

[0008] The present application aims to provide an inorganic material foaming stabilizing agent suitable for high-altitude air pressure environment, which comprises a stabilizing copolymer, a cellulose ether, a polyacrylamide, a bentonite and deionized water. The stabilizing copolymer is formed by copolymerization of dimethyl silicone oil, dimethyl disiloxane and polydimethylsiloxane crosslinked polymer.

[0009] The components in the inorganic material foaming stabilizing agent of the present application are stable in performance, can effectively improve the toughness and elasticity of the foam under high-altitude conditions, and form a protective film outside the bubble to play a protective role. The cellulose ether has water retention, thickening and retarding effects, the polyacrylamide is thickening and can improve the viscosity and stability, and they all belong to tackifying substances, which can thicken and increase the viscosity of the solution and reduce the flowability of the foam. The bentonite can absorb and retain water, thereby enhancing the stability of the bubble and preventing the bubble from breaking. The bentonite can reduce the contact area between bubbles and the pressure between bubbles, so as to make the bubble structure more stable. Through the synergistic effect of the components, the stabilizing agent of the present application is used for inorganic material foaming, the bubble wall strength is significantly improved, the bubble film viscosity is increased, the foam is uniform and tough, and the stability requirements of product foaming under high-altitude low-pressure conditions are met.

[0010] Further, the mass fraction of the components of the stabilizing copolymer is as follows: Dimethyl silicone oil 5-20 parts Dimethyl disiloxane 10-30 parts Polydimethylsiloxane crosslinked polymer 20-70 parts The molecular weight of the polydimethylsiloxane crosslinked polymer is 6000-10000.

[0011] Further, the mass percentage of the components of the inorganic material foaming stabilizing agent is as follows: Stabilizing copolymer 10-35% Cellulose ether 1-5% Polyacrylamide 1-8% Bentonite 2-10% Deionized water 20-65% Preferably, the viscosity of the cellulose ether is 100-1000 mPa·s.

[0012] The polyacrylamide has a molecular weight of 0.9-1.3 million.

[0013] The application also aims to provide a preparation method of the inorganic material foaming stabilizing agent suitable for high-altitude pressure environment, comprising the following steps, (1) Preparation of the stabilizing copolymer: the dimethyl silicone oil, dimethyldisiloxane and polydimethylsiloxane cross-linked polymer are weighed according to the above-mentioned ratio, and are uniformly mixed by stirring and dispersing to obtain the stabilizing copolymer. (2) The stabilizing copolymer, cellulose ether, polyacrylamide, bentonite and deionized water are weighed according to the above-mentioned ratio, the cellulose ether and bentonite are added into the deionized water while being dispersed and stirred, and after all the components are added, the stirring and dispersing are continuously carried out until a transparent gel-like solution is prepared. (3) The stabilizing copolymer obtained in step 1 and the polyacrylamide are uniformly mixed, and then the transparent gel-like solution prepared in step 2 is added, and after high-speed stirring and homogenization, the stabilizing agent is prepared.

[0014] Compared with the prior art, the application has the beneficial effects that: The inorganic material foaming stabilizing agent can be used for inorganic material foaming, can help to improve the strength of the bubble wall, increase the bubble film viscosity, make the foam uniform and tough, make the bubble foaming uniform, and make the bubble diameter size 0.2-0.5 mm without collapse, and the foam stabilizing effect is obviously enhanced, the foam stabilizing performance of the product foaming bubble under high-altitude low-pressure condition is significantly enhanced, and the stabilizing agent can be used not only in normal pressure environment, but also can meet the stabilizing demand in high-altitude low-pressure environment. DETAILED DESCRIPTION

[0015] The technical solutions of the application will be clearly and completely described below in combination with the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments. Based on the embodiments in the application, all the other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the application.

[0016] Embodiment 1 1. Preparation of the stabilizing copolymer The dimethyl silicone oil, dimethyldisiloxane and polydimethylsiloxane cross-linked polymer are weighed according to the mass ratio, and are uniformly mixed by high-speed stirring and dispersing to obtain the stabilizing copolymer. The polydimethylsiloxane cross-linked polymer has a molecular weight of 6000-10000, and the DC9040 product produced by Dow Corning Company is selected.

[0017] 2. Preparation of the inorganic material foaming stabilizing agent Weigh out the following components by mass percentage: 5% cellulose ether, 5% bentonite, 5% polyacrylamide, 20% of the foam-stabilized copolymer prepared in step 1, and 65% deionized water, wherein the viscosity of the cellulose ether is 400 mPa·s and the molecular weight of the polyacrylamide is 1 million.

[0018] Cellulose ether and bentonite are added to deionized water, and the mixture is slowly added while being dispersed and stirred. After all the ingredients have been added and soaked, the mixture is stirred at high speed until it is dispersed into a transparent gel-like solution.

[0019] The foam stabilizer is prepared by mixing the foam stabilizer copolymer synthesized in step 1 with polyacrylamide, adding the prepared transparent gel solution, and then stirring at high speed to homogenize and emulsify.

[0020] In the preparation of the foam-stabilizing copolymer, the copolymer synthesized from three raw materials exhibits stable performance and effectively improves the toughness and elasticity of the foam under high-altitude conditions, forming a protective film on the outside of the foam. Cellulose ether has water-retaining, thickening, and retarding effects, while polyacrylamide, as a thickener, can improve viscosity and stability. Both belong to the thickening class of substances, which can thicken and increase the viscosity of the solution, reducing the fluidity of the foam. Bentonite can adsorb and retain moisture, thereby enhancing the stability of the foam and preventing it from breaking. Bentonite can also reduce the contact area between bubbles, lower the pressure between bubbles, and make the foam structure more stable.

[0021] Application Example 1: Preparation of Gypsum Foamed Cementitious Materials Weigh out 50 parts by weight of gypsum powder, 1 part of gypsum foaming agent (whose components and dosages are: 47 parts water, 2 parts polyethylene oxide, 15 parts triethanolamine, 1 part sodium molybdate, 5 parts nanocellulose ether, 10 parts potassium aluminum sulfate dodecahydrate, 10 parts hydroxyethylidene diphosphate, 10 parts sodium pyrophosphate, which are mixed together), 36 parts water, 0.2 parts of the inorganic material foaming and stabilizing agent prepared in Example 1, and 3.2 parts of gypsum foaming agent (specifically hydrogen peroxide).

[0022] Add the gypsum foaming agent and the foam stabilizer to the weighed water and stir until well mixed. Then add gypsum powder and disperse it to ensure that the gypsum powder and solution are fully mixed. Finally, add the gypsum foaming agent, disperse for about 1 minute, pour into the mold or fill the product, and cure to obtain the gypsum foamed gelling material.

[0023] Comparative Example 1 Unlike Application Example 1, Comparative Example 1 did not include an inorganic foaming and stabilizing agent.

[0024] Weigh out 50 parts gypsum powder, 1 part gypsum foaming agent, 36 parts water, and 3.2 parts gypsum foaming agent according to the specified weight proportions. Add the gypsum foaming agent to the weighed water and stir to mix evenly. Then add the gypsum powder and disperse it to ensure that the gypsum powder and solution are fully mixed. Finally, add the gypsum foaming agent and disperse it to obtain the gypsum foamed cementitious material.

[0025] Performance testing The gypsum foaming gelling materials of Application Example 1 and Comparative Example 1 were stirred evenly and then placed into test chambers respectively. Based on the air pressure of the control at an altitude of 5000 meters being approximately 70.665 kPa and the air pressure of the control at an altitude of 3000 meters being approximately 83.998 kPa, the low-pressure test chamber was set with low air pressure values ​​of 66 kPa and 82 kPa respectively to simulate the environmental air pressure at high altitudes. The pressure deviation was (±1.8) kPa and the temperature deviation was (±0.5)℃.

[0026] The test results are shown in the table below:

[0027] Under simulated air pressure, it was observed that the foam of the foaming material in Application Example 1 was uniformly foamed with a foam diameter of 0.2-0.5 mm and no collapse, and the foam stabilization effect was significantly enhanced; it was observed that the foaming material in Comparative Example 1 collapsed after about 10 minutes.

[0028] Therefore, the inorganic foaming stabilizer of the present invention, used in inorganic foaming materials, helps to improve the strength of the bubble wall, increase the viscosity of the bubble film, make the foam uniform and tough, significantly enhance the foam stability of products under high altitude and low air pressure conditions, and meet the foam stability requirements under high altitude and low air pressure environments.

[0029] The above embodiments are for illustrative purposes only and are not intended to limit the invention. Those skilled in the art can make various changes or modifications without departing from the spirit and scope of the invention. Therefore, all equivalent technical solutions should also fall within the scope of the invention and should be defined by the claims.

Claims

1. An inorganic foaming and stabilizing agent suitable for high-altitude atmospheric pressure environments, characterized in that, Its components include foam stabilizer copolymer, cellulose ether, polyacrylamide, bentonite and deionized water, wherein the foam stabilizer copolymer is formed by copolymerization of dimethyl silicone oil, dimethyldisiloxane and polydimethylsiloxane crosslinked polymer.

2. The inorganic foaming and stabilizing agent according to claim 1, characterized in that, The foam-stabilizing copolymer has the following components in parts by mass: 5-20 parts of dimethyl silicone oil 10-30 parts of dimethyldisiloxane 20-70 parts of polydimethylsiloxane crosslinked polymer.

3. The inorganic foaming and stabilizing agent according to claim 2, characterized in that, The molecular weight of the polydimethylsiloxane crosslinked polymer is 6000-10000.

4. The inorganic foaming and stabilizing agent according to any one of claims 1-3, characterized in that, Its component mass percentage is, Foam stabilizer copolymer 10-35% Cellulose ether 1-5% Polyacrylamide 1-8% Bentonite 2-10% Deionized water 20-65%.

5. The inorganic foaming and stabilizing agent according to claim 4, characterized in that, The cellulose ether has a viscosity of 100-1000 mPa·s, and the polyacrylamide has a molecular weight of 900,000-1,300,000.

6. A method for preparing an inorganic foaming and stabilizing agent suitable for high-altitude atmospheric pressure environments as described in claim 1, characterized in that, Includes the following steps, (1) Preparation of foam stabilizer copolymer: Weigh dimethyl silicone oil, dimethyldisiloxane and polydimethylsiloxane crosslinked polymer according to the ratio, stir and disperse to mix evenly to obtain foam stabilizer copolymer; (2) Weigh out the foam stabilizer copolymer, cellulose ether, polyacrylamide, bentonite and deionized water according to the ratio. Add the cellulose ether and bentonite to the deionized water while dispersing and stirring. After all the ingredients are added, continue stirring and dispersing to obtain a transparent gel solution. (3) Mix the foam stabilizer copolymer obtained in step 1 and polyacrylamide evenly, then add the transparent gel solution obtained in step 2, stir and emulsify to obtain the inorganic material foam stabilizer.

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