Preparation method of high-temperature-resistant inorganic adhesive

Abstract

The invention belongs to the technical field of adhesives, and discloses a preparation method of a high-temperature-resistant inorganic adhesive. The preparation method comprises the following steps: uniformly mixing and stirring a base material and deionized water; adding the filler and the reinforcer in batches, and performing high-speed shearing dispersion; adding an auxiliary agent, stirring, and performing ultrasonic treatment; adjusting the viscosity; performing vacuum defoaming; and sealing and standing at room temperature to obtain the high-temperature-resistant inorganic adhesive. The inorganic adhesive prepared by the invention has stable long-acting high temperature resistance and good interface performance.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of adhesives, and particularly relates to a preparation method of a high-temperature-resistant inorganic adhesive. BACKGROUND

[0002] At present, inorganic adhesives need to have high strength and low density characteristics. The inorganic adhesive with sodium / potassium water glass as a matrix has high brittleness. In addition, some inorganic adhesives have poor comprehensive performance, such as high-temperature stability. With the increase of application scenarios, higher requirements are put forward for the heat resistance of adhesives in high-temperature environments. The existing products are prone to performance decline or failure problems under high temperature. In addition, the compatibility of the adhesives used in the bonding of heterogeneous materials such as aluminum alloys and carbon fibers is also insufficient. The interfacial bonding strength between the adhesives and the substrates is insufficient, which easily leads to delamination.

[0003] Therefore, there is an urgent need for an inorganic adhesive with good comprehensive performance to meet the above requirements. SUMMARY

[0004] The application aims to provide a preparation method of a high-temperature-resistant inorganic adhesive, and to prepare an inorganic adhesive with stable and long-acting high-temperature resistance.

[0005] A preparation method of a high-temperature-resistant inorganic adhesive, the preparation method comprising the following steps:

[0006] (1) mixing and stirring a base material and deionized water until uniform;

[0007] (2) adding fillers and reinforcing bodies in batches, and performing high-speed shearing dispersion;

[0008] (3) adding an additive, stirring, and performing ultrasonic treatment;

[0009] (4) adjusting the viscosity;

[0010] (5) vacuum degassing;

[0011] (6) sealing and standing at room temperature to obtain the high-temperature-resistant inorganic adhesive;

[0012] The high-temperature-resistant inorganic adhesive comprises the following components:

[0013] 40-50wt% of a base material

[0014] 25-35wt% of fillers

[0015] 10-15wt% of reinforcing bodies

[0016] 10-15wt% of an additive

[0017] 5-10wt% of deionized water.

[0018] Furthermore, the base material is a combination of sodium silicate and aluminum dihydrogen phosphate in a mass ratio of 3 to 5:1, with a purity of ≥99% and a particle size of 1-10 μm. Utilizing the high-temperature resistance of phosphate and the film-forming properties of silicate, a synergistic effect is achieved (temperature resistance up to 1500℃), and the high purity and particle size can be adjusted to influence high-temperature stability.

[0019] Furthermore, the filler is a combination of nano-alumina and rice husk ash in a mass ratio of 1:3 to 6, with a particle size of 300 to 500 nm; the rice husk ash contains amorphous SiO2 ≥ 90%. Replacing commercial silicon micropowder with rice husk ash reduces costs by 30% and is environmentally friendly.

[0020] Furthermore, the reinforcement is a combination of SiC and zirconium oxide powder in a mass ratio of 3-5:2, with a particle size of 50-100 nm. Its high thermal conductivity and thermal stability allow the adhesive to maintain its strength at high temperatures (>1500℃). The nanoparticles fill the micropores and simultaneously form a thermally conductive network, reducing localized thermal stress.

[0021] Furthermore, the auxiliary agent is a combination of Y(NO3)3 and B4C in a mass ratio of 2 to 4:1.

[0022] Furthermore, step (2) involves adding the filler and reinforcement in 2 to 4 portions, and dispersing them at a high speed of 1000-1500 rpm until no agglomeration occurs. Adding them in portions avoids stratification and improves the stability of the system.

[0023] Furthermore, in step (3), ultrasonic treatment is performed at 20-30 kHz for 10-15 minutes.

[0024] Furthermore, in step (4), the viscosity is controlled to be between 500-2000 cP at 25°C.

[0025] Furthermore, step (5) involves vacuum degassing at -0.095 MPa for 10-15 minutes.

[0026] Compared with the prior art, the advantages of the present invention are:

[0027] This invention uses sodium silicate and aluminum dihydrogen phosphate as base materials, and limits the purity and particle size of the materials to ensure stable combination and high-temperature stability. In addition, it incorporates a variety of functional components to effectively improve the overall performance.

[0028] Y(NO3)3 in the additive provides Y 3+ It can be converted into Y2O3 at high temperatures, promoting sintering densification and forming a eutectic phase with components such as Al2O3 / SiO2 (e.g., yttrium aluminum garnet Y3Al5O3). 12This process lowers the sintering temperature (by 200-300℃) and reduces porosity; Y₂O₃ pins grain boundaries, preventing filler particle coarsening at high temperatures and maintaining microstructural stability (especially above 1200℃), thus inhibiting abnormal grain growth and enhancing filler-matrix bonding. 3+ By adsorbing onto the surface of fillers (such as Al2O3), it reduces interfacial energy and improves the wettability between the silicate / phosphate matrix and the filler; it alleviates thermal stress, and the formed Y2O3 nanoparticles can buffer the mismatch of the coefficient of thermal expansion (CTE) and reduce the tendency to crack; it provides antioxidant protection by forming a protective film: in a high-temperature oxidizing environment, Y2O3 reacts with SiO2 to form a yttrium silicate glass layer, which blocks oxygen diffusion;

[0029] In addition, SiC and B4C can be used as a heat-resistant framework, suitable for applications with temperatures above 1500℃, offering high hardness (HV≥30GPa) and low density (2.52g / cm³). 3 This makes it an ideal choice for lightweight, high-strength fillers; at high temperatures, B4C oxidizes to form a B2O3 glass phase (melting point 450℃), which can flow and seal microcracks, while simultaneously forming more stable yttrium borates (such as YBO3) in synergy with Y2O3; B4C can also preferentially react with oxygen in the environment, protecting the matrix material from oxidation. Detailed Implementation

[0030] The following provides specific embodiments of a method for preparing a high-temperature resistant inorganic adhesive according to the present invention. It should be noted that the following examples are only for illustrating the present invention in more detail, and not for narrowing the scope of protection of the present invention. Improvements and adjustments made by those skilled in the art after reading this invention without departing from the concept of the present invention are all within the scope of protection claimed by the present invention.

[0031] A method for preparing a high-temperature resistant inorganic adhesive includes the following steps:

[0032] (1) The base material and deionized water are mixed in a reactor and stirred at 300-500 rpm at 18-23°C until homogeneous;

[0033] (2) Add the filler and reinforcement in 2 to 4 portions, and disperse them by high-speed shearing at 1000-1500 rpm until no agglomeration occurs;

[0034] (3) Add the additives, continue stirring for 20 min, and then perform ultrasonic treatment at 20-30 kHz for 10-15 min.

[0035] (4) Adjust the viscosity by adding or subtracting deionized water, and use a Brookfield viscometer to test the viscosity. Control the viscosity at 25°C to 500-2000 cP.

[0036] (5) Degas under vacuum at -0.095MPa for 10-15 minutes to eliminate bubbles;

[0037] (6) Allow the system to stand at room temperature for 24-48 hours to stabilize, and you will get a high-temperature resistant inorganic adhesive.

[0038] The components of the high-temperature resistant inorganic adhesive include the following:

[0039] Base material 40-50 wt%

[0040] 25-35 wt% of filler

[0041] 10-15 wt% of reinforcement

[0042] 10-15 wt% of additives

[0043] 5-10 wt% deionized water.

[0044] The base material is a combination of sodium silicate (modulus 2.5-3.2) and aluminum dihydrogen phosphate in a mass ratio of 3-5:1, with a purity ≥99% and a particle size of 1-10μm.

[0045] The filler is a combination of nano-alumina and rice husk ash in a mass ratio of 1:3 to 6, with a particle size of 300 to 500 nm; the rice husk ash contains ≥90% amorphous SiO2.

[0046] The reinforcement is a combination of SiC and zirconium oxide powder in a mass ratio of 3 to 5:2, with a particle size of 50-100 nm.

[0047] The additives are a combination of Y(NO3)3 and B4C in a mass ratio of 2 to 4:1.

[0048] Example 1

[0049] The components of the high-temperature resistant inorganic adhesive include the following:

[0050] 40wt% base material

[0051] 25wt% of filler

[0052] 15wt% of reinforcement

[0053] 15wt% of additives

[0054] 5 wt% deionized water.

[0055] A method for preparing a high-temperature resistant inorganic adhesive includes the following steps:

[0056] (1) The base material and deionized water are mixed in a reactor and stirred at 300 rpm at 20°C until homogeneous;

[0057] (2) Add the filler and reinforcement in three batches, and disperse them by high-speed shearing at 1200 rpm until no agglomeration occurs;

[0058] (3) Add the additives, continue stirring for 20 min, and sonicate at 25 kHz for 12 min;

[0059] (4) Adjust the viscosity by adding or subtracting deionized water, and use a Brookfield viscometer to test the viscosity. Control the viscosity at 25°C to 1000 cP.

[0060] (5) Degas under vacuum at -0.095MPa for 12 minutes to eliminate bubbles;

[0061] (6) Allow the system to stand at room temperature for 24 hours to stabilize, and then obtain the high-temperature resistant inorganic adhesive.

[0062] The base material is a combination of sodium silicate (modulus 2.8) and aluminum dihydrogen phosphate in a 3:1 mass ratio, with a purity ≥99% and a particle size of 5μm. The filler is a combination of nano-alumina and rice husk ash in a 1:3 mass ratio, with a particle size of 400nm; the rice husk ash contains ≥90% amorphous SiO2. The reinforcement is a combination of SiC and zirconium oxide powder in a 3:2 mass ratio, with a particle size of 70nm. The additive is a combination of Y(NO3)3 and B4C in a 2:1 mass ratio.

[0063] Example 2

[0064] The components of the high-temperature resistant inorganic adhesive include the following:

[0065] 40wt% base material

[0066] 30wt% of filler

[0067] 10wt% of reinforcement

[0068] 15wt% of additives

[0069] 5 wt% deionized water.

[0070] A method for preparing a high-temperature resistant inorganic adhesive includes the following steps:

[0071] (1) The base material and deionized water are mixed in a reactor and stirred at 300 rpm at 20°C until homogeneous;

[0072] (2) Add the filler and reinforcement in three batches, and disperse them by high-speed shearing at 1200 rpm until no agglomeration occurs;

[0073] (3) Add the additives, continue stirring for 20 min, and sonicate at 25 kHz for 12 min;

[0074] (4) Adjust the viscosity by adding or subtracting deionized water, and use a Brookfield viscometer to test the viscosity. Control the viscosity at 25°C to 1000 cP.

[0075] (5) Degas under vacuum at -0.095MPa for 12 minutes to eliminate bubbles;

[0076] (6) Allow the system to stand at room temperature for 24 hours to stabilize, and then obtain the high-temperature resistant inorganic adhesive.

[0077] The base material is a combination of sodium silicate (modulus 2.8) and aluminum dihydrogen phosphate in a mass ratio of 4:1, with a purity ≥99% and a particle size of 5μm. The filler is a combination of nano-alumina and rice husk ash in a mass ratio of 1:4, with a particle size of 400nm; the rice husk ash contains ≥90% amorphous SiO2. The reinforcement is a combination of SiC and zirconium oxide powder in a mass ratio of 4:2, with a particle size of 60nm. The additive is a combination of Y(NO3)3 and B4C in a mass ratio of 3:1.

[0078] Example 3

[0079] The components of the high-temperature resistant inorganic adhesive include the following:

[0080] 50wt% base material

[0081] 25wt% of filler

[0082] 10wt% of reinforcement

[0083] 10wt% of additives

[0084] 5 wt% deionized water.

[0085] A method for preparing a high-temperature resistant inorganic adhesive includes the following steps:

[0086] (1) The base material and deionized water are mixed in a reactor and stirred at 300 rpm at 20°C until homogeneous;

[0087] (2) Add the filler and reinforcement in three batches, and disperse them by high-speed shearing at 1200 rpm until no agglomeration occurs;

[0088] (3) Add the additives, continue stirring for 20 min, and sonicate at 25 kHz for 12 min;

[0089] (4) Adjust the viscosity by adding or subtracting deionized water, and use a Brookfield viscometer to test the viscosity. Control the viscosity at 25°C to 1000 cP.

[0090] (5) Degas under vacuum at -0.095MPa for 12 minutes to eliminate bubbles;

[0091] (6) Allow the system to stand at room temperature for 24 hours to stabilize, and then obtain the high-temperature resistant inorganic adhesive.

[0092] The base material is a combination of sodium silicate (modulus 2.8) and aluminum dihydrogen phosphate in a mass ratio of 5:1, with a purity ≥99% and a particle size of 5μm. The filler is a combination of nano-alumina and rice husk ash in a mass ratio of 1:6, with a particle size of 500nm; the rice husk ash contains ≥90% amorphous SiO2. The reinforcement is a combination of SiC and zirconium oxide powder in a mass ratio of 5:2, with a particle size of 60nm. The additive is a combination of Y(NO3)3 and B4C in a mass ratio of 4:1.

[0093] Comparative Example 1: Basically the same as Example 3, except that it lacks aluminum dihydrogen phosphate.

[0094] Comparative Example 2: Basically the same as Example 3, except that it lacks the adjuvant.

[0095] Comparative Example 3: Basically the same as Example 3, except that SiC is missing.

[0096] Thermal shock cycling was tested in alternating cycles of high temperature (1500℃) and high humidity (95% RH) (24h per cycle). 50 cracking tests were conducted. The tests revealed that Examples 1-3 did not crack after use, while Comparative Examples 1-3 showed varying degrees of cracking, with Comparative Example 2 showing the most significant cracking.

[0097] Note: The above embodiments are only used to illustrate the present invention and are not intended to limit the technical solutions described in the present invention. Therefore, although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the present invention. All technical solutions and improvements that do not depart from the spirit and scope of the present invention should be covered within the scope of the claims of the present invention.

Claims

1. A method for preparing a high-temperature resistant inorganic adhesive, characterized in that, The preparation method includes the following steps: (1) Take the base material and mix it with deionized water until it is uniform; (2) Add fillers and reinforcing materials in stages and disperse them by high-speed shearing; (3) Add additives, stir, and sonicate. (4) Adjust the viscosity; (5) Vacuum degassing; (6) After being sealed and left to stand at room temperature, a high-temperature resistant inorganic adhesive is obtained; The high-temperature resistant inorganic adhesive components include the following: Base material 40-50 wt% 25-35 wt% of filler 10-15 wt% of reinforcement 10-15 wt% of additives 5-10 wt% deionized water.

2. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, The base material is a combination of sodium silicate and aluminum dihydrogen phosphate in a mass ratio of 3 to 5:1, with a purity of ≥99% and a particle size of 1-10 μm.

3. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, The filler is a combination of nano-alumina and rice husk ash in a mass ratio of 1:3 to 6, with a particle size of 300 to 500 nm; the rice husk ash contains ≥90% amorphous SiO2.

4. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, The reinforcing agent is a combination of SiC and zirconium oxide powder in a mass ratio of 3 to 5:2, with a particle size of 50-100 nm.

5. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, The auxiliary agent is a combination of Y(NO3)3 and B4C in a mass ratio of 2 to 4:

1.

6. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, Step (2) involves adding filler and reinforcement in 2 to 4 batches, and dispersing them at a high speed of 1000-1500 rpm until no agglomeration occurs.

7. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, In step (3), ultrasonic treatment is performed at 20-30 kHz for 10-15 minutes.

8. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, The viscosity requirement in step (4) is to be controlled at 500-2000 cP at 25℃.

9. The method for preparing the high-temperature resistant inorganic adhesive according to claim 1, characterized in that, Step (5) involves vacuum degassing at -0.095 MPa for 10-15 minutes.