Fast-curing silicon-based material for cast composite fireproof glass and preparation method thereof

Abstract

The application belongs to the technical field of building fireproof materials, and particularly relates to a fast-curing silicon-based material for composite fireproof glass by the casting method and a preparation method. The method comprises the following steps: 1) obtaining a nano-silicon dioxide dispersion liquid; 2) mixing the nano-silicon dioxide dispersion liquid and a low-concentration potassium silicate solution; and 3) making the silicon dioxide crystallize under stirring to form a high-modulus potassium silicate thin layer on the surface of the silicon dioxide, and obtaining the nano-silicon dioxide dispersion liquid wrapped with a potassium silicate outer layer. The specific particle size silicon dioxide coated with potassium silicate can meet the process of the silicon-based composite fireproof glass without increasing the solution viscosity, can greatly reduce the reaction speed when reacting with potassium hydroxide, and can stabilize the solution viscosity at 3 hours after the reaction; meanwhile, the potassium hydroxide can be easily dissolved in the core layer to react at high temperature, so that the curing time is greatly shortened to less than 5 hours.

Description

Technical Field

[0001] This invention belongs to the field of building fireproof materials technology, specifically relating to a fast-curing silicon-based material for composite fireproof glass using the injection method and its preparation method. Background Technology

[0002] Currently, silicon-based composite fireproof glass is widely used in the global market due to its good weather resistance and fireproof and heat insulation performance. There are two manufacturing processes for silicon-based composite fireproof glass. One process involves making a cavity from glass, pouring in the reacted nano-silicon material, encapsulating it, and heating and curing it. The other process involves coating high-solids-content silicon-based material onto glass and laminating it to form multi-layer composite fireproof glass. Among these processes, the pouring method is widely accepted and implemented by small and medium-sized enterprises because of its simple process and low equipment investment.

[0003] The production of silicon-based composite fireproof glass by the infusion method mainly involves a solution prepared with silicon dioxide as the main material. After reacting with potassium hydroxide under certain process conditions, the air bubbles in the solution are removed, and the solution is poured into a glass cavity and sealed. The cavity material is then baked in an oven at 80 degrees Celsius for 10-18 hours. The cavity material is formed by the solidification of liquid into hydrated potassium silicate crystals with a certain modulus and solid content. These crystals are colorless and transparent solids at 0-80 degrees Celsius. When exposed to fire, they lose water and foam, forming a strong foam that provides heat insulation and fireproofing.

[0004] The production process of silicon-based composite fireproof glass by the infusion method is as follows: liquid preparation reaction for 1-2 hours; infusion for 1-3 hours; curing for 10-18 hours.

[0005] Currently, the materials used to manufacture silicon-based composite fireproof glass on the market are fumed silica powder or silica sol. The original particle size of the silica powder is between 100-200 nanometers, and the specific surface area is between 40-60 m². 2 With an oil absorption value of 0.4-0.6 ml / g, this type of powder is suitable for making silicone-based fire retardant solutions. Another type is silica sol raw material. To meet the requirements of fire retardant liquid production processes, only particles with a diameter of 100 nanometers or larger, and a particle size distribution within ±10, can be selected. Particles exceeding these specifications will extend the curing time by several hours or even longer. Particles below these specifications will result in a rapid viscosity increase during subsequent alkali addition reactions, leaving no time for processing.

[0006] Given the current situation where the production efficiency of infused silicon-based composite fireproof glass is low and energy consumption is high, we have discovered a method for preparing silicon dioxide that can significantly shorten the curing time while meeting the process requirements for silicon-based composite fireproof glass, reducing the original curing time of 10-18 hours to less than 5 hours. Summary of the Invention

[0007] To address the issues of low production efficiency and high energy consumption in the current production of cast-in-place silicon-based composite fireproof glass, this invention provides a fast-curing silicon-based material and its preparation method for cast-in-place composite fireproof glass. Based on a discovered method for preparing silicon dioxide, this invention can significantly shorten the curing time while meeting the process requirements for silicon-based composite fireproof glass, reducing the original curing time of 10-18 hours to less than 5 hours.

[0008] The technical solution provided by this invention is as follows:

[0009] A method for preparing a fast-curing silicon-based material for composite fireproof glass using an infusion method includes the following steps:

[0010] 1) Obtain a dispersion of nano-silica;

[0011] 2) Mix the nano-silica dispersion with a low-concentration potassium silicate solution;

[0012] 3) Silica crystals are grown under stirring, and a thin layer of high-modulus potassium silicate is formed on the surface of silica to obtain a nano-silica dispersion with potassium silicate coating.

[0013] Based on the above technical solution, a high-modulus potassium silicate thin layer is formed on the surface of the obtained silica. When this silica reacts with alkali (potassium hydroxide), it can significantly reduce the reaction rate, and the viscosity of the solution stabilizes to 3 hours after the reaction, which meets the filling time requirement for fireproof glass. At the same time, due to the small original particle size of silica, potassium hydroxide can easily dissolve the core layer reaction quickly during high-temperature curing, thus significantly shortening the curing time to 5 hours.

[0014] Specifically, in step 1): fumed silica is selected, with a primary particle size of 80-120 nanometers, preferably 80 nanometers; and a specific surface area of ​​40-60 m². 2 / g, preferably 50m 2 / g; oil absorption value is 0.4-0.6mL / g, preferably 0.45mL / g. Fumed silica is mixed with deionized water and subjected to ultrasonic treatment to obtain a nano-silica dispersion dispersed into native silica particles, wherein the weight ratio of nano-silica to deionized water is (48-51):100.

[0015] Based on the above technical solution, the nano-silica particles in the nano-silica dispersion have small particle sizes, which makes it easy for potassium hydroxide to quickly dissolve the core layer reaction during high-temperature curing, thus greatly shortening the curing time.

[0016] The power of ultrasonic treatment can be 200-500W, the treatment time can be 30-60 minutes, and the frequency can be 30-50kHz.

[0017] Based on the above technical solution, nano-silica can be effectively dispersed.

[0018] Furthermore, in step 2):

[0019] A potassium silicate solution with a modulus of 1.6-2.4 and a solid content of 20-40% is used; the preferred modulus is 1.8-2.2 and the preferred solid content is 25-35%.

[0020] The weight percentage of potassium silicate solution to the nano-silica dispersion obtained in step 1) is 0-10%, and not 0, preferably 3-6%.

[0021] The mixing temperature is 10-60 degrees Celsius, preferably 20-50 degrees Celsius.

[0022] Based on the above technical solution, low-concentration potassium silicate can form a composite structure with silicon dioxide during the silicon dioxide crystal growth process, and does not affect the original particle size of nano-silica.

[0023] Furthermore, in step 3):

[0024] The stirring speed is 10-100 rpm, preferably 60-80 rpm;

[0025] The reaction time is 1-3 hours, preferably 2.5 hours.

[0026] Specifically, in step 1): sodium silicate is treated with sulfuric acid to obtain a silicic acid solution. The silicic acid solution is then mixed with deionized water and subjected to ultrasonic treatment to obtain a nano-silica dispersion with a primary particle size of 50-80. The weight ratio of nano-silica to water is (48-51):100.

[0027] Specifically, the molar ratio of sulfuric acid to sodium silicate is 1:1.5-1:2.

[0028] Furthermore, in step 2):

[0029] A potassium silicate solution with a modulus of 1.6-2.4 and a solid content of 20-40% is used; the preferred modulus is 1.8-2.2 and the preferred solid content is 25-35%.

[0030] The weight percentage of potassium silicate solution and the nano-silica dispersion obtained in step 1) is 0-10%, preferably 3-6%;

[0031] The mixing temperature is 10-60 degrees Celsius, preferably 20-50 degrees Celsius.

[0032] Furthermore, in step 3):

[0033] The stirring speed is 10-100 rpm, preferably 60-80 rpm;

[0034] The reaction time is 1-3 hours, preferably 2.5 hours.

[0035] Furthermore, an antifoaming agent, pH adjuster, or dispersant may be added during the steps. The amounts of the antifoaming agent, pH adjuster, or dispersant are 0.1-0.5%, 1-3%, and 0.5-2% of the total amount of the nano-silica dispersion, respectively. Preferably, they are added in step 2).

[0036] Defoamers can be nonionic surfactants or alcohol ether compounds, pH adjusters can be organic acids, and dispersants can be polyethylene glycol, polyvinyl alcohol, and their derivatives, all of which can be achieved using existing technologies.

[0037] The present invention also provides a fast-curing silicon-based material for composite fireproof glass prepared by the above preparation method.

[0038] The fast-curing silicon-based material for composite fireproof glass provided by the above technical solution can significantly shorten the curing time while meeting the requirements of silicon-based composite fireproof glass process, reducing the original curing time of 10-18 hours to less than 5 hours.

[0039] This invention also provides a method for preparing silicon-based composite fireproof glass based on the pouring method, comprising the following steps:

[0040] 1) Mix the quick-setting silicon-based material for the injection-type composite fireproof glass with potassium hydroxide;

[0041] 2) Perform a reaction degassing treatment;

[0042] 3) Pour the mixture into the glass cavity, seal it, and allow it to cure.

[0043] in:

[0044] The reaction degassing temperature is 40-55℃, preferably 25-50℃, and more preferably 25-30℃; the reaction degassing time is 1-3 hours, preferably 2 hours.

[0045] The curing temperature is 75-85℃, preferably 60-85℃, and more preferably 70-80℃; the curing time is less than or equal to 5 hours.

[0046] The present invention also provides a silicon-based composite fireproof glass prepared according to the method.

[0047] In addition, other methods can be used to obtain nano-silica to form dispersions, such as sol-gel method, gas phase method, precipitation method, microemulsion method or hydrothermal method.

[0048] The beneficial effects of this invention are as follows:

[0049] 1) This invention, by coating potassium silicate with silica of a specific particle size, can achieve the desired effect without increasing the solution viscosity while meeting the requirements of silicon-based composite fireproof glass manufacturing processes. When reacting with potassium hydroxide, it can significantly reduce the reaction rate, and the solution viscosity stabilizes at 3 hours after the reaction. It has a reaction degassing time of 1-3 hours and an operating time of 1-3 hours. At the same time, it facilitates the rapid dissolution of the core layer reaction by potassium hydroxide during high-temperature curing, which greatly shortens the curing time from the original 10-18 hours to less than 5 hours.

[0050] 2) Silicon-based composite fireproof glass is prepared using fast-curing silicon-based materials through the injection method. It has good fire resistance and transparency, as well as good mechanical strength and weather resistance.

[0051] 3) Silicon-based composite fireproof glass can maintain good structural integrity and optical performance even in high-temperature environments, providing safer and more reliable fire protection for buildings, transportation and other fields;

[0052] 4) The method of the present invention is simple to operate, easy to industrialize, and has significant economic and social benefits. Detailed Implementation

[0053] The principles and features of the present invention are described below. The embodiments given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0054] Unless otherwise specified, the test methods used in the embodiments are conventional methods; unless otherwise specified, the materials and reagents used are commercially available.

[0055] Fumed silica can be made using Evonik X50 brand products.

[0056] Defoamers can be products from BASF or American Gas.

[0057] The dispersant can be a product of Dow Company.

[0058] pH adjusters can be boric acid or citric acid.

[0059] Examples 1 to 3 were prepared using fumed silica.

[0060] Example 1

[0061] The preparation method of fast-curing silicon-based material for composite fireproof glass by pouring includes the following steps:

[0062] 1) Obtain a dispersion of nano-silica;

[0063] 2) Mix the nano-silica dispersion with a low-concentration potassium silicate solution;

[0064] 3) Under stirring, silica crystals are grown, forming a thin layer of high-modulus potassium silicate on the silica surface, resulting in a nano-silica dispersion coated with potassium silicate.

[0065] In step 1): Fumed silica is selected, with a primary particle size distribution of 80-120 nanometers and a specific surface area of ​​50 m². 2 / g, with an oil absorption value of approximately 0.48mL / g, is mixed with deionized water and subjected to ultrasonic treatment to obtain a nano-silica dispersion containing native silica particles, wherein the weight ratio of nano-silica to deionized water is approximately 50:100.

[0066] In step 2), a potassium silicate solution with a modulus of 0.23 and a solid content of 30% is used. The weight percentage of the potassium silicate solution to the nano-silica dispersion obtained in step 1) is 8%. The mixing temperature is 60 degrees Celsius.

[0067] The amounts of defoamer, pH adjuster, and dispersant are 0.05%, 0.5%, and 1% of the total amount of nano-silica dispersion, respectively. Preferably, they are added together in step 2).

[0068] In step 3): the stirring speed is 90 rpm. The reaction time is 1.5 hours.

[0069] Example 2

[0070] Referring to Example 1, the difference is that the mixing temperature in step 2) is adjusted to 25 degrees Celsius, and the reaction time in step 3) is adjusted to 2 hours.

[0071] Example 3

[0072] Referring to Example 1, the difference is that the mixing temperature in step 2) is adjusted to 45 degrees Celsius, and the reaction time in step 3) is adjusted to 3 hours.

[0073] Examples 4 to 6 were prepared using sodium silicate.

[0074] Example 4

[0075] The preparation method of fast-curing silicon-based material for composite fireproof glass by pouring includes the following steps:

[0076] 1) Obtain a dispersion of nano-silica;

[0077] 2) Mix the nano-silica dispersion with a low-concentration potassium silicate solution;

[0078] 3) Under stirring, silica crystals are grown, forming a thin layer of high-modulus potassium silicate on the silica surface, resulting in a nano-silica dispersion coated with potassium silicate.

[0079] In step 1): Sodium silicate is treated with sulfuric acid to obtain a silicic acid solution. The silicic acid solution is then mixed with deionized water and subjected to ultrasonic treatment to obtain a nano-silica dispersion with a primary particle size of 50-80. The weight ratio of nano-silica to water is approximately 50:100.

[0080] In step 2), a potassium silicate solution with a modulus of 2.0 and a solid content of 40% is used. The weight percentage of the potassium silicate solution to the nano-silica dispersion obtained in step 1) is 10%. The mixing temperature is 65 degrees Celsius.

[0081] In step 3): the stirring speed is 60 rpm. The reaction time is 2 hours.

[0082] Example 5

[0083] Referring to Example 4, the difference is that the mixing temperature in step 2) is adjusted to 55 degrees Celsius, and the reaction time in step 3) is adjusted to 1.5 hours.

[0084] Example 6

[0085] Referring to Example 4, the difference is that the mixing temperature in step 2) is adjusted to 60 degrees Celsius, and the reaction time in step 3) is adjusted to 1 hour.

[0086] Comparative Example 1

[0087] Referring to Example 1, the difference is that: purchased virgin fumed silica with a larger particle size of 130-150 was used for preparation.

[0088] Comparative Example 2

[0089] Referring to Example 1, the difference is that: it is prepared using commercially available virgin fumed silica with a smaller particle size of 40-50.

[0090] Example of effect

[0091] The methods for preparing silicon-based composite fireproof glass using the pouring method obtained in the examples and comparative examples all adopt the following steps for comparison:

[0092] 1) Mix the quick-setting silicon-based material for the injection-cast composite fireproof glass with potassium hydroxide;

[0093] 2) Perform a reaction degassing treatment;

[0094] 3) Pour into the glass cavity, seal, and cure.

[0095] In step 1), the weight ratio of the fast-curing silicon-based material to potassium hydroxide for the injection-type composite fireproof glass is 6:1.

[0096] In step 2), the reaction degassing temperature is 40℃; the reaction degassing time is 1 hour.

[0097] In step 3), the curing temperature is 80℃.

[0098] Test content and data:

[0099] Example 1

[0100] The viscosity of the quick-curing silicon-based material for composite fireproof glass made by the injection method, after being mixed with potassium hydroxide, is 34 cps within 3 hours.

[0101] After 5 hours of curing, a hardness test was performed, yielding a Shore A score of 96. This data confirms complete curing.

[0102] The final silicon-based composite fireproof glass was tested:

[0103] The transparency value is 85%.

[0104] Its fire resistance meets the national standard GB15763.3.

[0105] The mechanical strength meets the national standard GB15763.3.

[0106] Example 2

[0107] The viscosity of the quick-curing silicon-based material for the injection-type composite fireproof glass, after being mixed with potassium hydroxide, is 40 cps within 3 hours.

[0108] After 5 hours of curing, a hardness test was conducted, yielding a Shore A value of 95.8. This data confirms complete curing.

[0109] The final silicon-based composite fireproof glass was tested:

[0110] The transparency value is 84.8%.

[0111] The fire resistance performance meets the national standard GB15763.3.

[0112] The mechanical strength meets the national standard GB15763.3.

[0113] Example 3

[0114] The viscosity of the quick-curing silicon-based material for composite fireproof glass made by the injection method, after being mixed with potassium hydroxide, is 28 cps within 3 hours.

[0115] After 5 hours of curing, a hardness test was conducted, yielding a Shore A value of 95.5. This data confirms complete curing.

[0116] The final silicon-based composite fireproof glass was tested:

[0117] The transparency value is 84.5%.

[0118] The fire resistance performance meets the national standard GB15763.3.

[0119] The mechanical strength meets the national standard GB15763.3.

[0120] Example 4

[0121] The viscosity of the quick-curing silicon-based material for composite fireproof glass made by the injection method, after being mixed with potassium hydroxide, is 30 cps within 3 hours.

[0122] After 5 hours of curing, a hardness test was performed, yielding a Shore A score of 96. This data confirms complete curing.

[0123] The final silicon-based composite fireproof glass was tested:

[0124] The transparency value is 84.6.

[0125] The fire resistance performance meets the national standard GB15763.3.

[0126] The mechanical strength meets the national standard GB15763.3.

[0127] Example 5

[0128] The viscosity of the quick-curing silicon-based material for composite fireproof glass made by the injection method, after being mixed with potassium hydroxide, is 28 cps within 3 hours.

[0129] After 5 hours of curing, a hardness test was conducted, yielding a Shore A value of 95.5. This data confirms complete curing.

[0130] The final silicon-based composite fireproof glass was tested:

[0131] The transparency value is 85.3%.

[0132] The fire resistance performance meets the national standard GB15763.3.

[0133] The mechanical strength meets the national standard GB15763.3.

[0134] Example 6

[0135] The viscosity of the quick-curing silicon-based material for composite fireproof glass made by the injection method, after being mixed with potassium hydroxide, is 33.5 cps within 3 hours.

[0136] After 5 hours of curing, a hardness test was conducted, yielding a Shore A value of 95.7. This data confirms complete curing.

[0137] The final silicon-based composite fireproof glass was tested:

[0138] The transparency value is 85.2%.

[0139] The fire resistance performance meets the national standard GB15763.3.

[0140] The mechanical strength meets the national standard GB15763.3.

[0141] Comparative Example 1

[0142] The viscosity of the quick-curing silicon-based material for composite fireproof glass made by the injection method, after being mixed with potassium hydroxide, is 22 CPS within 3 hours.

[0143] Hardness testing was conducted after 5 hours of curing, yielding a Shore A of 36. This data demonstrates that curing cannot be completed within 5 hours.

[0144] The final silicon-based composite fireproof glass was tested:

[0145] The transparency value is 35%.

[0146] Its fire resistance performance does not meet the national standard GB15763.3.

[0147] The mechanical strength does not meet the national standard GB15763.3.

[0148] It can be seen that the final silicon-based composite fireproof glass requires a longer curing time.

[0149] Comparative Example 2

[0150] When the fast-curing silicon-based material for composite fireproof glass produced by the pouring method is mixed with potassium hydroxide, the viscosity value after 3 hours is 268 cps. It can be seen that this viscosity value is insufficient for pouring, or that pouring will generate a large number of impact bubbles that cannot be eliminated.

[0151] Hardness tests were conducted after 5 hours of curing, and the results showed that curing could not be completed within 5 hours.

[0152] As can be seen from the examples and comparative examples, coating potassium silicate with silica of a specific particle size can achieve the desired effect without increasing the solution viscosity, while meeting the requirements of silicon-based composite fireproof glass manufacturing processes. When reacting with potassium hydroxide, the reaction rate can be significantly reduced, and the solution viscosity can be stabilized at 3 hours after the reaction. At the same time, during high-temperature curing, potassium hydroxide can be readily dissolved to react with the core layer, thereby significantly shortening the curing time to less than 5 hours.

[0153] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for preparing a fast-curing silicon-based material for use in a fire- resistant glass composite by infusion, characterized in that, The method comprises the following steps: 1) obtaining a nano-silica dispersion liquid; 2) mixing the nano-silica dispersion liquid and a low-concentration potassium silicate solution; 3) crystallizing the silica under stirring to form a thin layer of high-modulus potassium silicate on the surface of the silica, thereby obtaining a nano-silica dispersion liquid wrapped with an outer layer of potassium silicate.

2. The method for preparing fast-curing silicon-based material for composite fireproof glass by injection casting according to claim 1, characterized in that, In step 1), fumed silica with a primary particle size of 80-120 nm, a specific surface area of 40-60 m 2 / g, an oil absorption value of 0.4-0.6 mL / g was selected, mixed with deionized water and subjected to ultrasonic treatment to obtain a nanosilica dispersion in which the primary silica particles were dispersed, wherein the weight ratio of nanosilica to deionized water was (48-51):

100.

3. The method for preparing fast-curing silicon-based materials for composite fireproof glass by injection casting according to claim 2, characterized in that, In step 2): The potassium silicate solution has a modulus of 1.6-2.4 and a solid content of 20-40%; The weight percentage of the potassium silicate solution to the nano-silica dispersion liquid obtained in step 1) is 0-10%; The mixing temperature is 10-60 degrees.

4. The method for preparing fast-curing silicon-based material for composite fireproof glass by injection casting according to claim 3, characterized in that, In step 3): The stirring speed is 10-100 revolutions per minute; The reaction time is 1-3 hours.

5. The method for preparing fast-curing silicon-based material for composite fireproof glass by injection casting according to claim 1, characterized in that, In step 1): After treating the sodium silicate with sulfuric acid, a silicic acid solution is obtained, which is then mixed with deionized water and subjected to ultrasonic treatment to obtain a nano-silica dispersion liquid with a primary particle size of 50-80, wherein the weight ratio of nano-silica to water is (48-51):

100.

6. The method for preparing the fast-curing silicon-based material for composite fireproof glass by the pouring method according to claim 5, characterized in that, In step 2): The potassium silicate solution has a modulus of 1.6-2.4 and a solid content of 20-40%; The weight percentage of the potassium silicate solution to the nano-silica dispersion liquid obtained in step 1) is 0-10%; The mixing temperature is 10-60 degrees.

7. The method for preparing fast-curing silicon-based material for composite fireproof glass by injection casting according to claim 5, characterized in that, In step 3): The stirring speed is 10-100 revolutions per minute; The reaction time is 1-3 hours.

8. A fast-curing silica-based material for infusion composite fireproof glass prepared by the method according to any one of claims 1 to 7.

9. A method for producing a silicon-based composite fireproof glass based on a perfusion process, characterized in that, The method comprises the following steps: 1) mixing the fast-curing silica-based material for infusion composite fireproof glass according to claim 8 with potassium hydroxide; 2) performing reaction defoaming treatment; 3) infusing into a glass cavity to seal and solidify; Wherein: The reaction defoaming temperature is 40-55℃; the reaction defoaming time is 1-3 hours; The solidification temperature is 75-85℃; the solidification time is less than or equal to 5 hours.

10. A silica-based composite fireproof glass prepared by the method according to claim 9.