CN115820133A

CN115820133A - Silicic acid-based material with light-transmitting heat-insulating protective layer and manufacturing method of protective layer

Info

Publication number: CN115820133A
Application number: CN202211665934.8A
Authority: CN
Inventors: 张天
Original assignee: Silicon Products Beijing New Material Technology Co ltd
Current assignee: Silicon Products Beijing New Material Technology Co ltd
Priority date: 2022-12-23
Filing date: 2022-12-23
Publication date: 2023-03-21

Abstract

The invention relates to a method for producing a silicic acid-based material with a light-transmitting, heat-insulating protective layer which is produced by pouring without drying and has good intrinsic strength and optimum adhesion to glass, which has very good optical transparency, and which can be used with good effect if stabilized by means of polyols, in particular ethylene glycol or glycerol, preferably in combination with polymethylsiloxane or polydimethylsiloxane (hereinafter referred to as siloxane), and a protective layer whose base material contains an antifoam, an internal primer and the necessary additives, for example ammonia, in order to improve the appearance and the viscosity of the dispersion or of the protective layer before curing, and to extend the pouring time, i.e. after pouring onto the glass or between two glass pieces, the air can be vented more quickly or the air bubbles can be made smaller so that they are smaller or disappear during the curing process, i.e. are not visible visually.

Description

Silicic acid-based material with light-transmitting heat-insulating protective layer and manufacturing method of protective layer

Technical Field

The invention relates to the technical field of materials, in particular to a silicic acid-based material with a light-transmitting heat-insulating protective layer and a manufacturing method thereof.

Background

Safety glass refers to products which appear in succession at the beginning of the 20 th century and comprises tempered glass, laminated glass, bulletproof glass, fireproof glass and the like. The fireproof glass is divided into single-piece fireproof glass and composite fireproof glass, wherein the composite fireproof glass is formed by bonding two or more pieces of float glass or toughened glass together through an adhesive with fireproof performance and has a fireproof function.

The composite fireproof glass has both fireproof integrity and fireproof heat insulation, and under the condition of flame impact, the fireproof layer can be foamed and expanded to form a honeycomb ceramic protective layer to absorb a large amount of heat, and meanwhile, crystallized water molecules are released to protect the glass behind the fireproof glue layer from being burst, so that high-temperature flame and smoke are effectively isolated from escaping.

Fire-resistant glass of the insulating type is present in europe in the 70 s of the 20 th century. The "saint goban" company and the "pilkington" germany company, france in the 1970 s, respectively, have studied fire-resistant glasses of the thermal insulation type. Although the two companies adopt the silicic acid-based material as the main raw material and both the raw materials can meet the requirements of high-grade heat insulation and fire prevention, the manufacturing processes of the two companies are far away. In the initial stage of the invention, the raw materials can not reach the perfect degree, and microbubbles and yellowing occur, but the product tends to be perfect continuously in the process of continuous effort.

High-grade heat-insulating fireproof glass is widely applied to industrial products such as buildings, ships and the like in the mature process. Because the heat-insulation type fireproof glass can resist the impact of high-temperature flame in a fire scene after a fire occurs, and keeps the integrity and heat insulation of the fire-insulation type fireproof glass, the great loss of the fire to the personal safety and the property safety in a certain space range can be greatly reduced, and more precious time is provided for fire rescue.

In the 2010 s, some companies in China obtained raw materials similar to the silicic acid preparation of saint gobain by importing, but the initiative and the speaking right of the raw materials are held in European hands, and the price is not friendly.

The method for preparing the silicic acid preparation is obtained by research analysis, imitation and other techniques and means by individual manufacturers and research institutions in a long time. However, in a very early stage, under the condition that the original European chemical formula and principle are not clear, a plurality of chemical raw materials which are mutually interfered are added into the prepared raw materials, and the product does not rush to the horse-riding project through long test, so that the phenomena of air bubbles, glue running, degumming and atomization often occur after the product is used for half a year, and the problems cannot be solved. Even by the 2020 s, these companies and research institutes have not found a better way to solve these problems.

Disclosure of Invention

The invention provides a light-transmitting and anti-aging heat-insulating protective raw material and a protective layer made of the raw material, wherein the protective layer is manufactured in a pouring manner without drying, and has good inherent strength and optimal adhesion to glass. The protective layer has very good optical transparency.

The invention aims to provide a silicic acid-based material with a light-transmitting heat-insulating protective layer, which specifically comprises the following components in percentage;

35-52% of silicon dioxide; 30-50% of water; 0.5 to 0.7 percent of potassium hydroxide; 0-13% of alkyl siloxane; 0-6% of ammonia water solution and the balance of polyhydric alcohol.

Further, the following components are included;

47.0-48.5% of silicon dioxide; 33.8 to 30.9 percent of water; 0.6 plus or minus 0.1 percent of potassium hydroxide; 0-10% of alkyl siloxane; 0-2.5% of ammonia water solution, and the balance of polyol, wherein the polyol comprises at least 5% by weight.

Further, the following components are included;

47.0% of silicon dioxide; 32.8 percent of water; 0.6 percent of potassium hydroxide; 0.5-3% of alkyl siloxane; 0-0.5% of ammonia water solution, and the balance of polyhydric alcohol, wherein the polyhydric alcohol accounts for at least 5% by weight.

Further, the concrete comprises the following components in percentage by weight;

48.2 percent of silicon dioxide; 30.9 percent of water; 0.5 percent of potassium hydroxide; 0.5-3% of alkyl siloxane; 0-0.5% of ammonia water solution, and the balance of polyhydric alcohol, wherein the polyhydric alcohol accounts for at least 5% by weight.

Further, the polyol is glycerol or ethylene glycol, the polyol being present in an amount of 10-20%.

A method for producing a silicic acid-based material dispersion having a light-transmitting, heat-insulating protective layer,

(a) Stabilizing the silica dispersion with glycerol and/or ethylene glycol and potassium hydroxide;

(i) Precipitated silica

(ii) Fumed and/or precipitated silica and silica sols

(b) Potassium hydroxide;

are mixed with each other;

in the silicon dioxide dispersion, the addition amount of an ammonia water solution is 0.5%;

i) Providing an appropriate amount of water, adding at least a portion of the potassium hydroxide and at least a portion of the polyol

ii) continuous addition of silica;

dispersing at a temperature above 40 ℃ and cooling to <40 ℃.

A method for preparing silicic acid-based material dispersoid with a light-transmitting heat-insulating protective layer comprises the following steps;

adding water, a portion of the polyol, the siloxane, and a portion of the potassium hydroxide in a mixer;

heating the mixer to about 40 ℃ and starting stirring for about 10 minutes;

the liquid is pumped and circulated by a homogenizer, and is preferably connected to a nano ball mill, the homogenizer is designed to have the function of continuously adding silicon dioxide, particularly, powder is continuously injected into liquid flow through a side channel and is dispersed along the direction of the liquid flow;

during the dispersion circulation, the temperature is lowered to 40 ℃ by means of a cooling device, and the temperature of the mixer is maintained during the dispersion by means of pumping through the homogenizer until the power consumption is constant, generally at about 35A, as the energy input increases;

stirring under vacuum for 2 to 4 hours, cooling the mixer to 20 deg.C, and if necessary, adjusting the pH to about 10.5-10.9 with potassium hydroxide;

the dispersion was filtered using a 50 micron bag filter and filled into containers.

Further, the polyol is added in two portions, one portion before the addition of silica and the other portion after the start of dispersion.

introducing the dispersion into a mixer, opening the mixer, stirring at a rate of about 50rpm, and adding a potassium hydroxide solution while stirring, thereby producing a creamy material of high viscosity;

during the stirring, the temperature is raised, preferably to 45-60 ℃, in particular to about 55 ℃, and if the mixing heat is insufficient, the active heating can be carried out;

when the maximum temperature is reached, typically about 45-60 ℃ after 15 minutes, holding for 15-45 minutes until the viscosity is reduced, typically about 50mpa.s, and then cooling to 40-45 ℃;

the mixer is then evacuated, preferably <100mbar, in particular 50 to 90 mbar;

maintaining the temperature in the range of about 42-45 deg.C under the vacuum, boiling the mixture, and agitating the internal bubbles to the surface of the mixture and breaking them;

the viscosity increases to about 150-250mpa.s and the stirring speed decreases during degassing, typically about 5 revolutions per minute;

the boiling temperature under vacuum is long enough, usually 15-45 minutes, to boil the mixture in the container, and the air in the material is expelled in the form of bubbles;

the mixer is cooled to 20-25 c with cooling water as quickly as possible. Due to the rapid cooling, the material processing time is expected to be 3 hours, about 2-2.5 hours at 55 ℃;

to ensure that there are no bubbles, it is preferable to continue stirring at a rate of 5 rpm at 20-25 ℃ for about 1-1.5 hours, and then close the stirrer and vacuum, discharge the mixed material, which can be used to fill fire-resistant glass.

The dispersion produces a bubble-free transparent protective layer after curing and has excellent properties in fire tests.

Similarly, silica sols can be used, but depending on the initial concentration, concentration by removal of excess water may be required to be used.

adding the silica sol into the polyalcohol and the siloxane, uniformly stirring, heating to 45-60 ℃ under stirring if higher-concentration silica is required, starting vacuum, and boiling under a vacuum environment to remove water;

subsequently, a potassium hydroxide solution was added to the silica sol-containing mixture, and the resultant creamy state was stirred. Raising the temperature to about 45-50 ℃ and, if desired, heating to a temperature of 50-60 ℃ and after about 15-30 minutes reducing the viscosity to about 20-50mPa.s;

cooling to 40-45 deg.C after about 15-45 minutes, and vacuum-starting at 40-45 deg.C to ensure boiling of the materials in the mixer;

the mixture is then rapidly cooled to 20-25 ℃ to increase the duration of the infusion operation, which provides an infusion operation time of 6 hours, and the vacuum is maintained at a temperature of 20-25 ℃ for about 60 minutes to ensure that no air bubbles are present;

the viscosity rises again, typically to about 50-100mpa.s, at the end of mixing, the stirring and vacuum are turned off and the contents of the mixer are discharged.

The mixtures produced in the above-described manner are suitable for filling fire-resistant glass, the initial viscosity of 50-100mPa.s increasing slowly with time, which is why the pouring operation time is limited to less than 6 hours.

The use of siloxanes having defoaming action and primer action, without affecting the optical properties, whether prepared from dispersions or silica sols, together with ammonia can improve the processability and quality of the protective layer.

The above dispersion and silica sol may also be used in combination, depending on the solid content and particle size in the silica sol, which may control the characteristics of the protective layer. Pure silica sols have a low viscosity which is very suitable for processing and also permits a prolonged treatment time, but the refractory time is too short and can be optimized by the addition of precipitated silica and fumed silica.

The preparation infusion time can vary within wide limits depending on the ratio of silica dispersion to silica sol. For the silica dispersion compositions and the alkali-stabilized silica sols described above, it was found that the time of the pouring operation was also prolonged with increasing silica sol content.

Another advantage of the mixture of precipitated silica dispersion and silica sol is that the degassing is faster than with pure precipitated silica dispersion under lower vacuum conditions. In particular, degassing of the dispersion before mixing with the potassium hydroxide solution can be omitted, the degassing process being facilitated even more by the addition of novel defoamers, in particular polydimethylsiloxanes.

The characteristics are as follows: silica sol curing is largely dependent on particle size, and therefore, silica sol having a large surface area cures faster than silica sol having a small surface area when electrolyte is added.

In order to obtain the desired processing quality and final properties, it is advantageous to use silica sol mixtures having different surface areas, in particular products made from stable raw materials, since large surface area silica sols may be less concentrated than small surface area silica sols.

The silica sol can be purchased as a finished product as a raw material, is stable under acid or alkaline conditions in order to achieve the required stability, and is more or less highly concentrated depending on the particle size. In the context of the present application, alkali-stabilized silica sols are of particular importance, in particular silica sols stabilized with potassium hydroxide or ammonia. Since highly concentrated dispersions or silica sols are essential for the invention, the silica sols purchased must usually be concentrated. As mentioned above, this can be done by first adding a polyol, such as glycerol or ethylene glycol, for further stabilization, and then concentrating the silica sol by evaporating the water.

The two dispersions containing precipitated silica and silica sol are mixed in a dispersing apparatus at a temperature below 60 ℃ with high shear and stirring.

As described above, the method for producing a thermal insulation protective layer using the dispersion or the silica sol is characterized in that the dispersion or the silica sol is mixed with a potassium hydroxide solution and cured, and the curing is preferably performed without dehydration. In this case, a dispersion with potassium hydroxide added is poured into the cavity and then cured to form a solid protective layer, preferably while maintaining the water content at elevated temperatures. The molar ratio of silica to alkali metal oxide in the protective layer is preferably greater than 4.

In the context of the present invention, precipitated silicas or silica sols can be used with good results if stabilization is effected by means of polyols, in particular ethylene glycol or glycerol, but, since increased reactivity is found, it is advantageous to use them in combination with polymethylsiloxanes or polydimethylsiloxanes (referred to below as siloxanes).

The use of precipitated silica rather than fumed silica prior to the present invention was considered impossible due to the different material properties. Experiments have shown that the properties of these materials, in particular the proportion of Si-OH groups on the particle surface and the inhomogeneous particle size distribution, do not adversely affect the protective layer. In contrast, the first fire test showed that the fire performance was improved.

The advantage of using precipitated silica is that it is very inexpensive, but the production of homogeneous dispersions causes problems.

Various attempts have been made to obtain stable dispersions in which the silica particles are stabilized by polyol and potassium hydroxide before the addition means for preparing a suitable dispersion have been found.

The content of amorphous precipitated silica suitable for producing protective layers is more than 99 percent, and the specific surface area is about 20 to 100 square meters per gram. The silica content is 35 to 42% of the dispersion and a specific surface area of 80 to 100m2/g can be used, for more concentrated dispersions a specific surface area of 20 to 80m2/g can be used. The average primary particle size is typically 10 to 70 nm, especially 20 to 40 nm, and all particles are below the visible spectrum after curing, in which case larger average primary particle sizes can be used, the secondary particle size of the silica only having an effect on the curing speed (small particle sizes will accelerate curing), but not on the dispersion and the protective layer itself.

Defoamers, internal primers and necessary additives (e.g. ammonia) can be added to the base material of the protective layer to improve the appearance and viscosity of the dispersion or protective layer before curing, and also to prolong the time of the pouring process. The defoaming agent acts as a degassing during manufacture, i.e. after pouring onto the glass or between two pieces of glass, it can vent faster or make the bubbles smaller so that they are smaller or disappear during curing, i.e. are not visible visually. The primer has the function of reducing the adhesive force of the protective layer, so that the glass on the fire surface is promoted to be broken when a fire disaster happens, and then the glass falls off from the protective layer in a large area, and the protective layer is prevented from being torn by the broken glass.

It has been found in experiments that certain silicon-containing compounds act as defoamers and primers in the protective layer without affecting the final properties of the protective layer.

In particular, these compounds are polymethylsiloxanes or polydimethylsiloxanes having short alkyl groups, which can be used both as defoamers and as internal primers, alone or as a mixture. Suitable polydimethylsiloxanes are also known as dimethylsiloxanes or polysilanes.

The invention comprises ammonium salts of polysiloxanes, optionally together with free ammonia.

The anti-foaming effect of such compounds is common, for example, in the medical field. However, their suitability as defoamers in compositions for producing protective layers and also as primers is not known.

Without considering any theoretical hypothesis, the effect as an internal primer is based at least in part on the affinity of the glass surface for the siloxane, since the siloxane diffuses concentrated on the glass surface and, due to the action of the siloxane groups, reduces the concentration of surface groups to which the protective layer adheres, promoting detachment in the event of fire. In addition, the defoaming properties of the protective layer in the glass facilitate the escape of gas, thus facilitating the large-area shedding of broken glass over the protective layer.

The silica dispersion may be added to a protective layer composition of a defoamer or primer, which may be cured with potassium hydroxide. In these compositions, the siloxanes outgas better and thus increase the production speed or shorten the processing time.

The cured protective layer also has better fire-blocking properties than a similar protective layer without the siloxane.

The molar ratio of silica to alkali metal oxide of the protective layer in the cured state is greater than 4:1, which can characterize the polysilicate or the mixture of nano-sized polysilicates embedded therein, the silica particles being invisible to the naked eye. The moisture content of the solidified layer is finally in the range of 35% to 60%, the silica content is 30-55%, and the maximum content of alkali metal oxides of sodium oxide, potassium oxide, lithium oxide and mixtures thereof should be within 16%.

For the stabilization of the gas phase or of the precipitated silica or silica sol, suitable polyols, such as ethylene glycol, propylene glycol or glycerol, can be used.

This stabilized silica can be cured by the addition of a base. For example, sodium hydroxide, potassium hydroxide, and the like, with potassium hydroxide being preferred over sodium hydroxide.

The siloxane may be added to the silicate-or silica-containing component or the hardener component, or to the caustic potash of the hardener component. Hardeners are those compounds or compositions which, after addition, lead to curing of the protective layer. Since the dispersion is incapable of being degassed when using silica particles, it is advantageous to add the siloxane to the silica dispersion. For dispersions without the addition of silicone, which is also possible, but at least presently undesirable, since the precipitated silicic acid and silica sol mixture of the silica dispersion is generally not required during mixing of the dispersion with the hardener component, if silicone is used, it can be added as a third component, or the dispersion or potassium hydroxide can be added, while mixing the two components.

The amount of silicone added is about 0.1-10% based on the mass of the cured protective layer, preferably 0.5-2.5% for obtaining transparent glass, and up to 10% for translucent or only partially opaque glass.

Compared with the prior art, the invention has the beneficial effects that:

the method according to the invention allows the direct manufacture of composite bodies, the basic elements of which are, for example, glass, the glass sheets being at a distance from one another. In particular, in order to obtain a higher thermal insulation value, the thermal protection layer is formed from a plurality of groups, in which case it is necessary to arrange a multi-pane carrier body, each protection layer being arranged between two panes of glass and finally forming a composite. In this case, two sheets of glass are connected to each other at a certain distance, and a desired gap value is set. This bonding can be accomplished by butyl and silicone compounds, polysulfites, hot melt or fast curing rubber polymers, leaving the necessary open holes where the protective layer is poured. Subsequently, the cavity between the glasses was filled with the mixed resist compound and the pour opening was closed.

It is preferred to degas the protective layer prior to pouring, which ensures that the cured protective layer is free of bubbles, which could interfere with the optical quality of the insulating protective layer. However, it was experimentally confirmed that even if some fine bubbles appeared at the initial stage after curing, the fine bubbles were not disappeared by the action of siloxane after one week.

In order to improve the quality of the protective layer, the siloxane is added to the silicon dioxide-or silicate-containing composition or hardener before mixing, which means that the work of pretreating the glass with a primer can be dispensed with. However, it is within the scope of the invention to use an external primer in addition to or in place of the internal primer (e.g., if the defoamer has no or poor primer effect, or no defoamer is added). Such an (outer) primer layer is referred to as auxiliary layer in the context of the present invention.

Other materials having the desired optical properties may also be used as support for the thermal protective layer of the invention, in particular glass, provided they meet the technical and physical requirements, for example, heat resistance. In general, the resistance of the thermal barrier and protective layer is increased by high water content and silicone.

Detailed Description

The following description of the present invention is provided to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention and to make the above objects, features and advantages of the present invention more comprehensible.

The endpoints of the ranges and any values disclosed herein are not limited to the precise range or value, and such ranges or values should be understood to encompass values close to those ranges or values. For ranges of values, between the endpoints of each of the ranges and the individual values, and between the individual values may be combined with each other to yield one or more new ranges of values, which ranges of values should be considered as specifically disclosed herein.

The first embodiment is as follows:

the concrete components are as follows:

48.2% silica;

19.6% glycerol;

31.6% water;

0.6% potassium hydroxide;

preparation 1 (about 20 l):

standard mode was established by stirring water and glycerol in potassium hydroxide solution, precipitated silica stirring, homogenisation for 3 minutes, using a 50 micron filter bag.

The manufacturing parameters are as follows: temperature during mixing and dispersing: 25 ℃, time of dispersion in the circulation system: 60 minutes, time interval between dispersion and degassing: 5 minutes, jacket temperature at degassing: 40 ℃, degassing time: 20 minutes, pressure at degassing: 50 mbar, degassing followed by cooling: 10 ℃,50 micron filter

Preparation method 2 (about 20 l): water and first glycerin were stirred in potassium hydroxide solution, precipitated silica was stirred, second glycerin was homogenized for 3 minutes, and a standard model was established using a 5 micron filter bag. The second embodiment is as follows:

preparation of a Dispersion of precipitated silica

Production equipment:

a 200 liter mixer made of stainless steel with a multi-layered jacket was used, which required a support vacuum structure so that it did not collapse under vacuum. Multiple jackets are used to circulate heating/cooling water, approximately 50-60 liters of medium water capacity for rapid warming and cooling. The stirring unit consists of a variable frequency anchor type stirring paddle, the variable frequency speed is 1-85 r/min, and the stirrer is driven by a 2.2 kilowatt speed reduction motor.

The mixer is equipped with viewing windows and illumination to observe the changes and state of the mixing.

The heating device consisted of a water heater with a flow rate of 40 liters/minute.

The cooling device consists of a continuous cooler and a 125 liter cold water reservoir to achieve rapid cooling of the mixer medium.

The vacuum pump, working on the venturi system principle, can achieve a vacuum value of about 70 mbar.

An in-line homogenizer or ball mill with a powder feed port.

The concrete components are as follows:

30.9% deionized water;

19.6% glycerol;

48.2% silica powder;

0.5% potassium hydroxide;

0.8% polydimethylsiloxane;

the specific operation is as follows:

water, glycerin, silicone, and potassium hydroxide were placed in a mixer, which was heated to 40 ℃, stirred at 50rpm, and stirred for about 10 minutes. Then, liquid phase circulation is performed with stirring by a dispersing device, silica is added, this step is accomplished by a homogenizer or nanosphere mill, the powder is continuously sucked from the side channel and enters into the liquid flow with the dispersing agent for grinding and dispersion, after all the powder enters, further dispersing and grinding are performed in the circulation until the minimum particle size is achieved. During dispersion, the power consumption of the disperser increases and the temperature rises. The temperature was maintained at about 40 ℃ by cooling and the power consumption was constant at about 35A, which was taken as a measure of uniform dispersion. The mass was then stirred at 40 ℃ under vacuum for 2 hours, after which the reactor was cooled to 20 ℃ and, if necessary, adjusted to a pH of about 10.5 to 10.9 with potassium hydroxide. Finally the dispersion was filled into plastic containers through a 50 micron filter.

The third concrete embodiment:

protective layer of dispersion prepared according to example two

Mixing the above dispersion with potassium hydroxide to form a dispersion protective layer of the composition:

36.99% deionized water;

14.39% glycerol;

34.52% silica powder;

13.71% potassium hydroxide;

0.58% polydimethylsiloxane;

apparatus (see example 2):

stirring, vacuum, cooling/heating jackets;

a heating unit;

a cooling unit;

vacuum pump, <100mbar;

the materials used were:

the dispersion prepared according to example 2 had a potassium hydroxide solution composition:

50% potassium hydroxide;

50% of water;

the specific process flow is as follows:

the 73.45% dispersion was initially added, the stirrer was turned on and 26.55% potassium hydroxide solution was added. The mixture is allowed to react with stirring, the temperature is increased to form a high viscosity creamy state, after about 15 minutes the maximum temperature of 45-50 ℃ is reached, and then the viscosity is reduced to about 50mPa.s within 15-45 minutes. The mixer is cooled to 40-45 ℃, the vacuum is turned on, the boiling temperature in the specific vacuum range of about 40-45 ℃ is maintained, the mixture is boiled and the bubbles are agitated to the surface and burst. After stirring for about 30-45 minutes, the mixer was rapidly cooled to increase the priming time. The vacuum is maintained for 60-90 minutes to ensure that there are no air bubbles, after which the mixture is used to fill the fire-resistant glass.

And (3) fire prevention test:

by using the protective layer, the fireproof glass with the size of 1200mm multiplied by 2400mm is manufactured, and the structure is 5mm toughened glass, 6mm protective layer and 5mm toughened glass. A 39 minute refractory time was achieved, thereby achieving an a0.30 rating.

The fourth concrete embodiment:

another method for producing novel protective layer by precipitating silicon dioxide

Production equipment:

same as in example 2 or 3

The concrete components are as follows:

32.3% deionized water <10 μ S conductivity;

19.6% glycerol (anhydrous);

47.% silica;

0.6% potassium hydroxide;

0.5% polydimethylsiloxane;

the specific process flow is as follows:

the 73.45% silica dispersion was initially added, the stirrer was turned on, and then 26.55% potassium hydroxide solution was added. The silica and potassium hydroxide react under agitation to form a high viscosity cream and after about 15 minutes, a maximum temperature of about 50-60 c should be reached, and if this temperature does not meet the mixing requirements, it may be further heated. At this time the viscosity decreased to about 50mpa.s, after about 15 to 45 minutes, the whole was cooled to 40 to 45 ℃ after reaching the maximum temperature.

The vacuum was then turned on, stirring, and the temperature was 40-45 ℃, the mixture was boiled for 15-45 minutes to allow the air in the material to be evacuated by the vacuum, and it was observed that the bubbles were stirred to the surface and burst.

After about 15-45 minutes, the reactor was cooled to 20-25 ℃ as quickly as possible to obtain a 3 hour perfusion run time. The vacuum is maintained at a temperature of 20-25 c for about 60-90 minutes with stirring to ensure that there are no air bubbles. The agitator was turned off, then the vacuum was turned off and the material was discharged from the mixer.

The mixture thus obtained is very suitable for filling with fire-resistant glass.

And (3) fire prevention test:

by using the protective layer, the fireproof glass with the size of 1200mm multiplied by 2400mm and the structure of 5mm toughened glass, 6mm protective layer and 5mm toughened glass are manufactured. The fireproofing time was 37 minutes, thus achieving a rating of a 0.30.

The fifth concrete embodiment:

a novel fireproof layer prepared by a method of adding ammonia into precipitated silicon dioxide;

production equipment:

same as example 2

The concrete components are as follows:

silica dispersion composition:

47% silicon dioxide;

19.6% glycerol;

0.5% polydimethylsiloxane;

0.6% potassium hydroxide;

32.3% deionized water;

potassium hydroxide solution composition:

50% potassium hydroxide;

50% of water;

composition of ammonia solution:

32% ammonia;

68% of water;

the specific process flow is as follows:

73% of the silica dispersion and 0.5% of the ammonia solution were introduced into the mixer and the stirrer was switched on. Then 26.5% potassium hydroxide is added and the mixture is reacted with stirring to a high viscosity cream. After about 15 minutes, a maximum temperature of about 45-50 ℃ was reached, heating was continued to bring the mixture to 50-60 ℃ and the viscosity was reduced to about 50mPa.s. This pressureless mixing and heating process takes approximately 15-45 minutes, then it is cooled to 40-45 ℃, then the vacuum is turned on, the temperature is maintained at 42-45 ℃, the mixture is stirred for 15-30 minutes, the mixture is boiled and bubbles are stirred to the surface and burst, and the viscosity slowly rises again. After that, it was rapidly cooled to 20-25 ℃ to obtain a perfusion operation time of 3 hours. The mixture is suitable for filling fire-resistant glass.

As a result:

it was observed that with the addition of ammonia solution under vacuum, less bubbles appeared on the surface of the mixture and the boiling was less vigorous (the boiling was more vigorous without the addition of ammonia), which shortens the process time and increases the cost efficiency, while improving the optical properties.

And (3) fire prevention test:

by using the protective layer, the fireproof glass with the size of 1200mm multiplied by 2400mm and the structure of 5mm toughened glass, 6mm protective layer and 5mm toughened glass are manufactured. The fire protection time was 38 minutes, thus achieving a rating of a 0.30.

The sixth specific embodiment:

preparing a protective layer by using silica sol;

production equipment:

a 500ml round bottom flask equipped with a magnetic stirrer as reaction vessel.

Heating and cooling;

a glass circulator attached to the round-bottom flask and equipped with a 500ml flask as a collection vessel vacuum pump attached to the reaction flask;

the concrete components are as follows:

silica sol composition:

50% (solids content) silica;

50% deionized water;

potassium hydroxide solution composition:

50% potassium hydroxide;

50% deionized water;

siloxane:

polydimethylsiloxane;

a polyol;

glycerol;

the specific process flow is as follows:

first 100% silica sol (50% silica content) was added to which 0.5% siloxane and 19.6% glycerol were added. The magnetic stirrer was turned on and stirred for 5 minutes to obtain a homogeneous liquid, the water bath was heated to about 45-50 ℃ with stirring, and the vacuum was turned on. The mixture was then freed of 17.1% of water by vacuum boiling, condensed water was obtained by a reflux condenser and collected in a flask to determine the amount of dehydration. The vacuum was turned off and the reaction vessel was depressurized, the reflux condenser was removed and the reaction flask was cooled to 20-25 ℃ with stirring.

A73.45% mixture of silica sol, defoamer, glycerol was placed in a flask, 26.55% potassium hydroxide solution was added and stirring was started. The mixture containing silica sol and potassium hydroxide reacts under agitation to form high viscosity cream which reaches a maximum temperature of about 45-50 c after about 15 minutes. The mixture is heated continuously to 50-60 ℃ and after about 15-30 minutes the viscosity drops to about 50mpa.s, which takes about 15-45 minutes without vacuum mixing and heating. Subsequently, it is cooled to 40-45 ℃ with stirring, the vacuum is turned on, the temperature of 40-45 ℃ is maintained under vacuum for 15-30 minutes, the mixture in the reactor is boiled and the air in the material is evacuated by means of air bubbles. The mixture in the reaction flask was then rapidly cooled in a water bath to 20-25 ℃ to slow down the reaction with the alkali metal silicate, resulting in a 3 hour pour time. The vacuum was held for 60 minutes to ensure that there were no air bubbles. The viscosity again rose to about 150-250mpa.s, the stirring was turned off, the vacuum was turned off, and the reaction flask was drained.

The mixtures prepared in this way are suitable for filling fire-resistant glass.

These results were confirmed in a 20 liter mixer and 500mm by 500mm sample glass was made for fire resistance testing.

And (3) fire prevention test:

the sample size is 500mm multiplied by 500mm, and the structure is 5mm toughened glass, 6mm protective layer and 5mm toughened glass. These samples, had reached a fire resistance time of 40 minutes. This corresponds to a classification level of a 0.30.

The seventh specific embodiment:

preparation of silica dispersions of precipitated silica, water, glycerol, potassium hydroxide, silica sol and polysiloxane.

Production equipment:

see examples 2 and 3

Specific example seven (a):

preparing a dispersion containing precipitated silica;

the concrete components are as follows:

32.3% deionized water;

19.6% glycerol;

47.0% silica powder;

0.6% potassium hydroxide;

0.5% polydimethylsiloxane.

The specific process flow is as follows:

water, glycerin, antifoam and potassium hydroxide were added and stirred for 10 minutes. Thereafter, the addition of silica is started by an in-line homogenizer or a nanoball mill, and is continuously added while circulating. The power consumption of the disperser increased to about 35A, with a consequent increase in temperature due to the increase in energy input. Thus, the mixer temperature was maintained at about 40 ℃ by cooling, and the material was circulated through the disperser until the power consumption was constant. Followed by stirring under vacuum at 40 ℃ for 2 hours, and then the mixer was cooled to 20 ℃.

The product was stored in a container through a 50 micron filter.

Specific example seven (B):

preparing silica sol mixed with glycerol;

the concrete components are as follows:

100% silica sol;

19.6% glycerol;

0.5% siloxane;

the specific process flow is as follows:

the silica sol, glycerol and siloxane were placed in a mixer, heated to 60-70 ℃ and stirred for 15 minutes. Subsequently, the vacuum was turned on, the distiller was adjusted to no reflux ratio and 17.1% of the water was evaporated off compared to the sol template. The vacuum was turned off, the mixer was depressurized and cooled to 20 ℃.

The product was stored in a container with a 50 micron filter or placed directly in a mixer for processing (see example seven (C)).

Specific example seven (C):

a composition containing 47.0% silica (precipitated silica and silica sol), 19.6% glycerol dispersion was prepared.

The concrete components are as follows:

a 50% modified silica sol according to example 7B;

a 50% silica dispersion according to example 7A;

specific example seven (C):

the modified silica sol prepared according to example 7B and the silica dispersion prepared according to example 7A were poured into a mixer and circulated through the dispersion apparatus for 1 hour with stirring, the temperature being maintained at about 40 ℃.

Stored in a container through a 50 micron bag filter.

Specific example seven (D):

fire resistant glass was prepared according to the mixture of example 7C;

the materials used were:

potassium hydroxide;

the process is as follows:

other mixtures with different ratios of precipitated silica dispersion to silica sol were prepared as described in example 7C, and after addition of potassium hydroxide, protective or fire-resistant glass (a 0.30\1200 × 2400mm \5mm toughened glass 6mm protective layer) was prepared.

Curing was carried out at 80 ℃ for 8 hours without additional water.

Although preferred examples of the present invention are described in the present application, it should be clearly understood that the present invention is not limited thereto and may be otherwise embodied within the scope of the following claims.

It will be evident to those skilled in the art that the invention is not limited to the details of the foregoing illustrative embodiments, and that the present invention may be embodied in other specific forms without departing from the spirit or essential attributes thereof. The present embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

Furthermore, it should be understood that although the present description refers to embodiments, not every embodiment may contain only a single embodiment, and such description is for clarity only, and those skilled in the art should integrate the description, and the embodiments may be combined as appropriate to form other embodiments understood by those skilled in the art.

Claims

1. A silicic acid-based material having a light-transmissive heat-insulating protective layer, characterized in that; the concrete comprises the following components in percentage by weight;

2. The silicate-based material having a light-transmissive heat-insulating protective layer according to claim 1, wherein; the concrete comprises the following components in percentage by weight;

47.0-48.5% of silicon dioxide; 33.8 to 30.9 percent of water; 0.6 plus or minus 0.1 percent of potassium hydroxide; 0-10% of alkyl siloxane; 0-2.5% of ammonia water solution, and the balance of polyhydric alcohol, wherein the polyhydric alcohol accounts for at least 5% by weight.

3. The silicate-based material having a light-transmissive heat-insulating protective layer according to claim 1, wherein; the concrete comprises the following components in percentage by weight;

4. The silicate-based material having a light-transmissive heat-insulating protective layer according to claim 1, wherein; the concrete comprises the following components in percentage by weight;

5. The silicic acid-based material having a light-transmitting heat insulating protective layer according to any one of claims 1 to 4, wherein; the polyol is glycerol or ethylene glycol, the polyol being present in an amount of 10-20%.

6. The method for producing a protective layer of a silicic acid-based material having a light-transmitting heat insulating protective layer according to any one of claims 1 to 4, wherein;

(i) Precipitated silica

(ii) Fumed and/or precipitated silica and silica sols

(b) Potassium hydroxide;

are mixed with each other;

ii) continuous addition of silica;

dispersing at a temperature above 40 ℃ and cooling to <40 ℃.

7. The method of producing a protective layer of a silicic acid-based material having a light-transmissive heat insulating protective layer according to any one of claim 6, wherein; the preparation method comprises the following steps;

heating the mixer to about 40 ℃ and starting stirring for about 10 minutes;

during the dispersion circulation, the temperature is lowered to 40 ℃ by means of a cooling device, and the temperature of the mixer is maintained during the dispersion by pumping through the homogenizer until the power consumption is constant, generally at about 35A, as the energy input increases;

8. The method of producing a protective layer of a silicate-based material having a light-transmissive heat-insulating protective layer as claimed in any one of claim 7, wherein; the polyol is added in two portions, one portion before the addition of the silica and the other portion after the start of the dispersion.

9. The method for producing a protective layer of a silicic acid-based material having a light-transmitting heat insulating protective layer according to any one of claims 1 to 6, wherein; the preparation method comprises the following steps;

during the stirring, the temperature is raised, preferably to 45-60 ℃, in particular to about 55 ℃, and if the mixing heat is insufficient, active heating can be carried out;

the mixer is then evacuated, preferably <100mbar, in particular 50 to 90 mbar;

maintaining the temperature at about 42-45 deg.C in the above vacuum range to boil the mixture, and stirring and breaking the internal bubbles to the surface of the mixture;

the mixer was cooled to 20-25 ℃ with cooling water as quickly as possible. Due to the rapid cooling, the material processing time is expected to be 3 hours, about 2-2.5 hours at 55 ℃;

10. The method for producing a protective layer of a silicic acid-based material having a light-transmitting heat insulating protective layer according to any one of claims 1 to 6, wherein; the preparation method comprises the following steps;

the viscosity rises again, typically to about 50-100mpa.s, and at the end of mixing, the stirring and vacuum are turned off and the contents of the mixer are discharged.