Red mud-based geopolymer inorganic reflective coating and preparation method thereof

Abstract

The invention relates to the technical field of inorganic coating manufacturing, and discloses a red mud-based geopolymer inorganic reflective coating and a preparation method thereof.The red mud-based geopolymer inorganic reflective coating is prepared from Bayer process red mud, a sodium silicate solution, solid sodium hydroxide, inorganic emulsion, titanium dioxide, talcum powder, a defoaming agent and a flatting agent. The invention also discloses a preparation method of the glass bead. The Bayer process red mud and the alkali activator are used as main film forming substances, and the generated geopolymer cementing material can effectively improve the appearance of a paint film and improve the mechanical property. By adding glass beads with different mesh numbers, the reflective effect of the coating is improved. According to the semi-blind equalization method for the DVB-S2 satellite system, based on the characteristics that a frame header and a pilot frequency in a frame structure of the DVB-S2 satellite system are known and fixed in position, the updating direction of a tap coefficient of an equalizer is guided by using a minimum mean square algorithm of a known partial sequence. In the first half iteration time of blind equalization, a sliding window variable step size multi-mode blind equalization algorithm capable of rapidly reducing errors is used to calculate an equalizer tap coefficient, and inter-symbol interference is reduced. In the last half iteration time of the blind equalization, a decision guidance algorithm with higher accuracy is used, and a smaller steady-state error is obtained while the steady state of the equalizer is ensured.

Description

Technical Field

[0001] The present application belongs to the field of coating technology, and specifically relates to a red mud-based polymer inorganic reflective coating and a preparation method thereof. Background Art

[0002] Highway tunnels are characterized by strong closure, large changes in light and darkness, and strict speed control, which have great limitations in ventilation, lighting, sight distance, disaster relief, etc. If a traffic accident occurs in a tunnel, it is very likely to lead to a secondary accident, bringing great difficulties to emergency management and rescue work.

[0003] In order to ensure the driving safety of highway tunnels and improve driving comfort, taking reasonable measures to illuminate the tunnels is the current development focus.

[0004] Red mud is an industrial solid waste. Random stacking or landfilling will cause environmental pollution. Using red mud and alkali activators as geopolymer materials can effectively realize the recycling of solid waste resources. Using the cementitious material generated by the reaction as the main film-forming substance can effectively enhance the fire retardant and mechanical properties of the coating.

[0005] At present, most of the coatings used for tunnel inner wall painting are gray and blue inorganic coatings, which have weak diffuse reflection ability, and the light and dark changes before and after the vehicle enters the tunnel are large, and the lighting effect in the tunnel is weak, which is not conducive to driving safety. Inorganic coatings with reflective effects can effectively enhance the reflectivity of tunnel coatings, improve tunnel lighting effects, and ensure driving safety. Summary of the invention

[0006] Aiming at the defects of current inorganic coatings for tunnels, the present invention enhances the reflective effect and use effect of the coating under the concept of environmental protection, and proposes a red mud-based polymer inorganic reflective coating and a preparation method thereof.

[0007] Preferably, the red mud-based polymer inorganic reflective coating is used for tunnel interior decoration and mine cave brightening coating.

[0008] The beneficial effects of the present invention are: The present invention uses red mud and alkaline activator as the main film-forming substances, adjusts the ratio of red mud and alkaline activator by compounding sodium silicate solution and solid sodium hydroxide, and utilizes the three-dimensional mesh gelling material produced by the reaction of the two to improve the mechanical properties of the coating. Adding styrene acrylic emulsion to the above coating can improve the film-forming state of the coating and effectively reduce the cracking phenomenon of the paint film. Adding mesh size to the above coating can fill glass microbeads with each other, supplemented with titanium dioxide and color paste, to improve the reflective properties of the coating. The red mud-based polymer inorganic reflective coating proposed by the present invention has good adhesion to the base layer, good mechanical properties of the paint film, high pencil hardness, and high reflection coefficient. In addition, the organic matter components in the coating are effectively reduced, and the fireproof performance is excellent. It can effectively improve the lighting effect of the tunnel. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 It is a schematic diagram of the reflective principle of reflective coatings in related technologies.

[0010] Figure 2 It is a schematic diagram of the reflective coating structure in the related art. DETAILED DESCRIPTION

[0011] To explain the technical content of the present invention in detail, the following is explained in conjunction with the embodiments. The test methods used in the examples are conventional methods unless otherwise specified; the materials, reagents, etc. used are all commercially available unless otherwise specified, and the described embodiments are only part of the present invention, not all embodiments.

[0012] As an embodiment of the present invention, a red mud-based polymer inorganic reflective coating is provided, comprising the following materials in parts by weight: 40-50 parts of Bayer red mud, 30-40 parts of sodium silicate solution, 3-6 parts of solid sodium hydroxide, 10-20 parts of inorganic emulsion, 10-20 parts of titanium dioxide, 5-10 parts of talc, 0-0.5 parts of defoaming agent, 0-0.5 parts of leveling agent, 0-0.5 parts of dispersant, 1-3 parts of anti-settling agent, 5-10 parts of color paste, 30-50 parts of 240 mesh glass microspheres, and 10-15 parts of 300 mesh glass microspheres.

[0013] As an embodiment of the present invention, the modulus of the modified water glass solution is 1.4, and the water-binder ratio of the slurry is 0.52, wherein when the water-binder ratio is calculated, the water content in the commercially available water glass solution is used as the water in the water-binder ratio. The alkali activator is prepared by mixing the water glass solution and solid NaOH in a certain proportion.

[0014] As an embodiment of the present invention, the total mass fraction of red mud and alkali activator in the red mud-based polymer inorganic reflective coating is 60-80%. The present invention optimizes the content of red mud and alkali activator and reasonably controls the amount of three-dimensional gelling material produced, thereby effectively enhancing the mechanical properties and apparent state of the reflective coating.

[0015] As an embodiment of the present invention, the mass of the inorganic emulsion is preferably 15-20 parts, so as to improve the anti-cracking performance of the red mud-based polymer inorganic reflective coating and enhance the film-forming effect.

[0016] As an embodiment of the present invention, the mass of the titanium dioxide is preferably 10-15 parts, so as to improve the whiteness of the coating and enhance the reflective effect of the paint film.

[0017] As an embodiment of the present invention, the mass of the 240-mesh glass beads is preferably 40-50 parts, and the mass of the 300-mesh glass beads is preferably 10-15 parts. Glass beads of different particle sizes are filled with each other. When mixing, the glass beads are added slowly to avoid collision and wear between them.

[0018] As an embodiment of the present invention, after the two kinds of glass microbeads of mesh sizes are completely poured in, color paste is added for color adjustment, and then stirred for 10 minutes to obtain a flat red mud-based polymer inorganic reflective coating.

[0019] Table 1 Performance test of red mud-based polymer inorganic reflective coating

Claims

1. A red mud-based polymer inorganic reflective coating, characterized in that: The raw materials of the coating include, by mass, 40-50 parts of Bayer red mud, 30-40 parts of sodium silicate solution, 3-6 parts of solid sodium hydroxide, 10-20 parts of inorganic emulsion, 10-20 parts of titanium dioxide, 5-10 parts of talc, 0-0.5 parts of defoaming agent, 0-0.5 parts of leveling agent, 0-0.5 parts of dispersant, 1-3 parts of anti-settling agent, 5-10 parts of color paste, 30-50 parts of 240-mesh glass microbeads, and 10-15 parts of 300-mesh glass microbeads.

2. The red mud-based polymer inorganic reflective coating according to claim 1, characterized in that: The Bayer process red mud is a waste material generated during the production of electrolytic aluminum, and its main components are SiO2, Fe2O3, Al2O3, Na2O, and CaO.

3. The red mud-based polymer inorganic reflective coating according to claim 1, characterized in that: The sodium silicate solution is Na2O·2.8SiO2, wherein the mass fraction of Na2O is 11% and the mass fraction of SiO2 is 33%.

4. The red mud-based polymer inorganic reflective coating according to claim 1, characterized in that: The mass of the sodium silicate solution and the Bayer red mud in the red mud-based polymerized inorganic reflective coating accounts for 60-80% of the total mass.

5. The red mud-based polymer inorganic reflective coating according to claim 1, characterized in that: The defoaming agent is an organic silicon defoaming agent, the dispersant is a silicate dispersant LBCB-1, and the inorganic emulsion is a styrene acrylic emulsion.

6. The method for preparing the red mud-based polymer inorganic reflective coating according to any one of claims 1 to 5, characterized in that: The method comprises the following preparation steps: Step 1: Mix solid sodium hydroxide and sodium silicate solution and add water to prepare an alkaline activator; Step 2: After the alkaline activator prepared in step 1 cools to room temperature, Bayer red mud is added to obtain a base material; Step 3: Stir the base material in step 2 for 10 minutes, add titanium dioxide, talcum powder, dispersant, and leveling agent, stir evenly, and grind to a particle size of 300-800 mesh; Step 4: Finally, add 240-mesh and 300-mesh glass microbeads, anti-settling agent, and color paste, and stir thoroughly to obtain the red mud-based polymer inorganic reflective coating.

7. The red mud-based polymer inorganic reflective coating according to claim 7, characterized in that: The stirring temperature in steps 4, 5 and 6 is 20-35°C.

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