Mesoporous heat preservation and insulation felt with hydrophobicity and preparation process of mesoporous heat preservation and insulation felt

Abstract

The invention relates to the technical field of heat preservation felts, in particular to a mesoporous heat preservation and insulation felt with hydrophobicity and a preparation technology of the mesoporous heat preservation and insulation felt. In order to enhance the heat insulation performance of the heat preservation felt, a mesoporous material is mixed with a hydrophobic modified resin material to enhance the heat preservation and insulation felt; fluorosilicone modified silane is prepared, fluorine elements and silicon elements are introduced into the fluorosilicone modified silane, sulfydryl groups introduced in the reaction process are reserved, the fluorosilicone modified silane further participates in subsequent cross-linking of polyurethane emulsion, the cross-linking degree of the resin is increased, and the physical performance of the resin is improved; the fluorine element and the silicon element are introduced in the process, so that the hydrophobicity of the material can be effectively improved, and the heat insulation capability of the heat insulation felt in a humid environment is improved; on the basis, a mesoporous material is further introduced into the hydrophobic polyurethane emulsion, and the defect that the thermal conductivity is improved due to the fact that the polyurethane emulsion modifies the heat preservation felt is overcome by means of the hollow characteristic of the mesoporous material.

Description

Technical Field

[0001] The invention relates to the technical field of thermal insulation felts, in particular to a hydrophobic mesoporous thermal insulation felt and a preparation process thereof. Background Art

[0002] With the rapid development of the country's industry, the problem of energy waste in industrial production has become more serious. Thermal insulation is of great help to the rational use of energy. It can isolate and reduce heat loss, thereby reducing energy consumption.

[0003] Currently, commonly used industrial insulation products are mainly traditional materials such as ceramic fiberboard, rock wool board, and wax stone brick, which have high thermal conductivity and brittle texture. Although aerogel products have extremely high thermal insulation ability, aerogel is easy to break after long-term use and has a short lifespan. Fiber felt products have the characteristics of soft texture and long-term use, but fiber felt products also have the problem of high thermal conductivity and large heat loss. Summary of the invention

[0004] The object of the present invention is to provide a hydrophobic mesoporous thermal insulation felt and a preparation process thereof, so as to solve the problems raised in the prior art.

[0005] To achieve the above object, the present invention provides the following technical solution: a preparation process of a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0006] S1. preparing a hydrophobic polyurethane emulsion;

[0007] The polycarbonate diol is heated to 105-110°C, dried for 1.5-2h, and then fluorosilicone-modified silane is added thereto. After stirring and mixing for 2-4h, stirring is stopped, and after cooling to room temperature, isophorol diisocyanate and dibutyltin dilaurate are added thereto. The temperature is raised to 78-82°C, and stirred for reaction for 0.5-1.5h. Then, 2,2-dimethylolpropionic acid is added thereto. The temperature is raised to 60-62°C, and the reaction is continued for 2-4h. The temperature is then lowered to 30-35°C, triethylamine is added for neutralization, and deionized water is added thereto. The mixture is stirred at a high speed of 1200-2400rpm for 15-30min to obtain a hydrophobic polyurethane emulsion.

[0008] S2. The mesoporous silica was mixed with a hydrophobic polyurethane emulsion, and the mixture was stirred at a high speed of 1200-2400 rpm for 15-30 min to obtain a hydrophobic mesoporous emulsion;

[0009] S3. Immerse the thermal insulation felt body in the hydrophobic mesoporous emulsion, evacuate the air pressure to 500-1000Pa, immerse for 3-5 minutes, increase the pressure to 0.5-0.8MPa, continue immersing for 5-10 minutes, pull out the felt body, place it at 105-120℃, dry it for 4-6 hours, and obtain a hydrophobic mesoporous thermal insulation felt.

[0010] Furthermore, in step S1, the preparation method of the fluorosilicone-modified silane is:

[0011] a. After nitrogen is passed into dimethyl sulfoxide for 0.5-4h, the mixture is cooled to a constant temperature in an ice-water bath, tetramethoxysilane and sodium hydroxide are added thereto, mixed evenly, bis-aminopropyl polydimethylsiloxane is added thereto, the temperature is raised to 85-90°C, the reaction is stirred for 4-12h, and the excess solvent is removed by rotary evaporation to obtain amino-terminated silane;

[0012] b. Disperse the terminal amino silane in DMF, stir and mix evenly, add concentrated sulfuric acid thereto, continue mixing for 3-5 minutes, and then drop the mixture into 1,3-propanedithiol. During the dropwise addition, control the temperature of the reaction system to 4-15°C. After the dropwise addition is completed, heat to 78-85°C, stir and react for 1.5-5 hours, stop heating, and cool to constant temperature in an ice-water bath. Add an equal volume of deionized water to DMF, stir vigorously for 1-3 minutes, and allow to stand for stratification. After removing the aqueous phase, evaporate the remaining mixture in vacuo to constant weight to obtain terminal mercapto silane;

[0013] c. The terminal mercaptosilane was dispersed again in DMF, to which benzoin butyl ether and 2-(perfluorobutyl) ethyl acrylate were added, and the mixture was protected by nitrogen atmosphere. After ultraviolet irradiation for 45-90 minutes, the excess solvent was removed by rotary evaporation to obtain fluorosilicone-modified silane.

[0014] Furthermore, in step a, the mass ratio of tetramethoxysilane, sodium hydroxide and bisaminopropyl polydimethylsiloxane is 1:(0.03-0.05):(6.5-8.5) in parts by weight.

[0015] Furthermore, in step b, the mass ratio of the amino-terminated silane, concentrated sulfuric acid and 1,3-propanedithiol is 1:(0.05-0.08):(0.25-0.31) in parts by weight.

[0016] Furthermore, in step c, the mass ratio of the terminal mercaptosilane, benzoin butyl ether, and 2-(perfluorobutyl)ethyl acrylate is 1:(0.02-0.04):(0.28-0.36) in parts by weight.

[0017] Further, in step S1, the hydrophobic polyurethane emulsion is composed of 42-48 parts of polycarbonate diol, 6-10 parts of fluorosilicone-modified silane, 12-16 parts of isophorol diisocyanate, 0.2-1 parts of dibutyltin dilaurate, 3-3.5 parts of 2,2-dimethylolpropionic acid, 2-2.5 parts of triethylamine and 180-260 parts of deionized water in parts by weight;

[0018] Wherein, the Mn of the polycarbonate diol is 1800-2500.

[0019] Furthermore, in step S2, the mass ratio of the hydrophobic polyurethane emulsion to the mesoporous silica is 1:(0.15-0.4) in parts by weight.

[0020] Furthermore, in step S3, the thermal insulation felt body is any one of glass fiber felt, basalt fiber felt, and aluminum silicate fiber felt with a thickness of 1-9 mm.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] Since thermal insulation felt is a fiber felt insulation material, the essence of its insulation is to use the fiber structure to capture air and hinder the flow of air. Due to the low thermal conductivity of air, the air in the thermal insulation felt is enclosed between the fibers to form an insulation layer, thereby reducing the conduction and convection of heat; however, the structure formed by the fiber felt is not a closed structure, and air can still circulate in it and exchange with the outside gas. Therefore, in humid weather, due to the high humidity of the air, the thermal insulation felt will absorb water and become damp, which will greatly increase the heat transfer effect of the thermal insulation felt and seriously affect the thermal insulation capacity of the thermal insulation felt. Therefore, this application uses a mesoporous material mixed with a hydrophobic modified resin material to enhance the thermal insulation felt;

[0023] The present invention first uses tetramethoxysilane as a raw material, reacts it with bisaminopropyl polydimethylsiloxane containing an amino group in an acidic environment, thereby generating a terminal amino silane of a four-arm structure, and then reacts it with 1,3-propanedithiol containing a mercapto group, and further grafts a mercapto group therein. On this basis, the terminal mercapto silane is mixed with 2-(perfluorobutyl)ethyl acrylate containing a fluorine element, and under the action of a photoinitiator, the mercapto group reacts with a double bond, thereby finally generating a fluorine-silicon-modified silane containing fluorine, silicon and a mercapto group. The introduction of fluorine and silicon elements can greatly improve the hydrophobicity of the resin, thereby improving the performance of the thermal insulation felt in a humid environment, and the retention of the terminal mercapto group can enable the fluorine-silicon-modified silane prepared by the present invention to further participate in the crosslinking of the subsequent polyurethane emulsion, thereby increasing the crosslinking degree of the resin and improving its physical properties.

[0024] On this basis, the present invention further introduces mesoporous materials into the hydrophobic polyurethane emulsion, and utilizes the hollow characteristics of the mesoporous materials to improve the defect of increased thermal conductivity caused by the polyurethane emulsion-modified thermal insulation felt. DETAILED DESCRIPTION

[0025] Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in the field without making any creative work shall fall within the scope of protection of the present invention.

[0026] The polycarbonate diol used in this application has a Mn of 2000; the mesoporous silica used is XFF11 type monodisperse mesoporous silica; the thermal insulation felt used is a glass fiber felt with a thickness of 6 mm;

[0027] Example 1. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0028] S1. preparing a hydrophobic polyurethane emulsion;

[0029] By weight, 45 parts of polycarbonate diol were heated to 105°C, dried for 2 hours, and then 6 parts of fluorosilicone-modified silane were added thereto. After stirring and mixing for 2 hours, stirring was stopped, and after cooling to room temperature, 14.5 parts of isophorol diisocyanate and 0.8 parts of dibutyltin dilaurate were added thereto. The temperature was raised to 78°C, stirred and reacted for 1 hour, and then 3.2 parts of 2,2-dimethylol propionic acid were added thereto. The temperature was raised to 62°C, and the reaction was continued for 4 hours, and then the temperature was lowered to 35°C. After neutralization by adding 2 parts of triethylamine, 230 parts of deionized water were added, and the mixture was stirred at a high speed of 1600 rpm for 25 minutes to obtain a hydrophobic polyurethane emulsion;

[0030] Wherein, the preparation method of fluorinated silicon-modified silane is:

[0031] a. After nitrogen was introduced into dimethyl sulfoxide for 2 hours, it was cooled to a constant temperature in an ice-water bath, 1 part of tetramethoxysilane and 0.04 parts of phosphoric acid were added thereto, mixed evenly, 6.5 parts of bis-aminopropyl polydimethylsiloxane were added thereto, the temperature was raised to 85°C, the reaction was stirred for 8 hours, and the excess solvent was removed by rotary evaporation to obtain amino-terminated silane;

[0032] b. Disperse 1 part of terminal aminosilane in DMF by weight, stir and mix evenly, add 0.05 parts of concentrated sulfuric acid thereto, continue mixing for 5 minutes, and then drop the mixture into 0.25 parts of 1,3-propanedithiol. During the addition, control the temperature of the reaction system to 4-8°C. After the addition is completed, heat to 82°C, stir and react for 4 hours, stop heating, and cool to constant temperature in an ice-water bath. Add an equal volume of deionized water to DMF, stir vigorously for 3 minutes, and let stand for stratification. After removing the aqueous phase, evaporate the remaining mixture in vacuo to constant weight to obtain terminal mercaptosilane;

[0033] c. By weight, 1 part of the terminal mercaptosilane was dispersed again in DMF, to which 0.04 parts of benzoin butyl ether and 0.28 parts of 2-(perfluorobutyl) ethyl acrylate were added, and the reaction was protected by a nitrogen atmosphere and irradiated with ultraviolet light for 80 minutes, and then the excess solvent was removed by rotary evaporation to obtain a fluorosilicone-modified silane;

[0034] S2. In parts by weight, 0.15 parts of mesoporous silica were mixed with 1 part of a hydrophobic polyurethane emulsion, and the mixture was stirred at a high speed of 1600 rpm for 25 min to obtain a hydrophobic mesoporous emulsion;

[0035] S3. Immerse the thermal insulation felt body in the hydrophobic mesoporous emulsion, evacuate the air pressure to 800Pa, immerse for 3 minutes, increase the pressure to 0.75MPa, continue immersing for 8 minutes, pull out the felt body, place it in a 115℃ environment, and dry it for 4-6 hours to obtain a hydrophobic mesoporous thermal insulation felt.

[0036] Example 2. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0037] Compared with Example 1, this example increases the amount of fluorine-silicon-modified silane added in step S1;

[0038] S1. preparing a hydrophobic polyurethane emulsion;

[0039] By weight, 45 parts of polycarbonate diol were heated to 105°C, dried for 2 hours, and then 10 parts of fluorosilicone-modified silane were added thereto. After stirring and mixing for 2 hours, stirring was stopped, and after cooling to room temperature, 14.5 parts of isophorol diisocyanate and 0.8 parts of dibutyltin dilaurate were added thereto. The temperature was raised to 78°C, stirred and reacted for 1 hour, and then 3.2 parts of 2,2-dimethylol propionic acid were added thereto. The temperature was raised to 62°C, and the reaction was continued for 4 hours, and then the temperature was lowered to 35°C. After neutralization by adding 2 parts of triethylamine, 230 parts of deionized water were added, and the mixture was stirred at a high speed of 1600 rpm for 25 minutes to obtain a hydrophobic polyurethane emulsion;

[0040] S2. In parts by weight, 0.15 parts of mesoporous silica were mixed with 1 part of a hydrophobic polyurethane emulsion, and the mixture was stirred at a high speed of 1600 rpm for 25 min to obtain a hydrophobic mesoporous emulsion;

[0041] S3. Immerse the thermal insulation felt body in the hydrophobic mesoporous emulsion, evacuate the air pressure to 800Pa, immerse for 3 minutes, increase the pressure to 0.75MPa, continue immersing for 8 minutes, pull out the felt body, place it in a 115℃ environment, and dry it for 4-6 hours to obtain a hydrophobic mesoporous thermal insulation felt.

[0042] Example 3. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0043] Compared with Example 1, this example increases the amount of bisaminopropyl polydimethylsiloxane added in step a;

[0044] Wherein, the preparation method of fluorinated silicon-modified silane is:

[0045] a. After nitrogen was introduced into dimethyl sulfoxide for 2 hours, the mixture was cooled to a constant temperature in an ice-water bath, 1 part of tetramethoxysilane and 0.04 parts of phosphoric acid were added thereto, and after mixing, 8.5 parts of bis-aminopropyl polydimethylsiloxane were added thereto, the temperature was raised to 85°C, the reaction was stirred for 8 hours, and the excess solvent was removed by rotary evaporation to obtain amino-terminated silane;

[0046] b. Disperse 1 part of terminal aminosilane in DMF by weight, stir and mix evenly, add 0.05 parts of concentrated sulfuric acid thereto, continue mixing for 5 minutes, and then drop the mixture into 0.25 parts of 1,3-propanedithiol. During the addition, control the temperature of the reaction system to 4-8°C. After the addition is completed, heat to 82°C, stir and react for 4 hours, stop heating, and cool to constant temperature in an ice-water bath. Add an equal volume of deionized water to DMF, stir vigorously for 3 minutes, and let stand for stratification. After removing the aqueous phase, evaporate the remaining mixture in vacuo to constant weight to obtain terminal mercaptosilane;

[0047] c. By weight, 1 part of terminal mercaptosilane was dispersed again in DMF, to which 0.04 parts of benzoin butyl ether and 0.28 parts of 2-(perfluorobutyl) ethyl acrylate were added, and the mixture was protected by nitrogen atmosphere and irradiated with ultraviolet light for 80 minutes, and then the excess solvent was removed by rotary evaporation to obtain fluorosilicone-modified silane.

[0048] Example 4. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0049] Compared with Example 3, this example increases the amount of 1,3-propanedithiol added in step b;

[0050] Wherein, the preparation method of fluorinated silicon-modified silane is:

[0051] a. After nitrogen was introduced into dimethyl sulfoxide for 2 hours, the mixture was cooled to a constant temperature in an ice-water bath, 1 part of tetramethoxysilane and 0.04 parts of phosphoric acid were added thereto, and after mixing, 8.5 parts of bis-aminopropyl polydimethylsiloxane were added thereto, the temperature was raised to 85°C, the reaction was stirred for 8 hours, and the excess solvent was removed by rotary evaporation to obtain amino-terminated silane;

[0052] b. Disperse 1 part of terminal aminosilane in DMF by weight, stir and mix evenly, add 0.05 parts of concentrated sulfuric acid thereto, continue mixing for 5 minutes, and then dropwise add the mixture into 0.31 parts of 1,3-propanedithiol. During the dropwise addition, control the temperature of the reaction system to 4-8°C. After the dropwise addition is completed, heat to 82°C, stir and react for 4 hours, stop heating, and cool to constant temperature in an ice-water bath. Add an equal volume of deionized water to DMF, stir vigorously for 3 minutes, and allow to stand for stratification. After removing the aqueous phase, evaporate the remaining mixture in vacuo to constant weight to obtain terminal mercaptosilane;

[0053] c. By weight, 1 part of terminal mercaptosilane was dispersed again in DMF, to which 0.04 parts of benzoin butyl ether and 0.28 parts of 2-(perfluorobutyl) ethyl acrylate were added, and the mixture was protected by nitrogen atmosphere and irradiated with ultraviolet light for 80 minutes, and then the excess solvent was removed by rotary evaporation to obtain fluorosilicone-modified silane.

[0054] Example 5. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0055] Compared with Example 4, this example increases the amount of 2-(perfluorobutyl)ethyl acrylate added in step c;

[0056] Wherein, the preparation method of fluorinated silicon-modified silane is:

[0057] a. After nitrogen was introduced into dimethyl sulfoxide for 2 hours, the mixture was cooled to a constant temperature in an ice-water bath, 1 part of tetramethoxysilane and 0.04 parts of phosphoric acid were added thereto, and after mixing, 8.5 parts of bis-aminopropyl polydimethylsiloxane were added thereto, the temperature was raised to 85°C, the reaction was stirred for 8 hours, and the excess solvent was removed by rotary evaporation to obtain amino-terminated silane;

[0058] b. Disperse 1 part of terminal aminosilane in DMF by weight, stir and mix evenly, add 0.05 parts of concentrated sulfuric acid thereto, continue mixing for 5 minutes, and then dropwise add the mixture into 0.31 parts of 1,3-propanedithiol. During the dropwise addition, control the temperature of the reaction system to 4-8°C. After the dropwise addition is completed, heat to 82°C, stir and react for 4 hours, stop heating, and cool to constant temperature in an ice-water bath. Add an equal volume of deionized water to DMF, stir vigorously for 3 minutes, and allow to stand for stratification. After removing the aqueous phase, evaporate the remaining mixture in vacuo to constant weight to obtain terminal mercaptosilane;

[0059] c. By weight, 1 part of terminal mercaptosilane was dispersed again in DMF, to which 0.04 parts of benzoin butyl ether and 0.36 parts of 2-(perfluorobutyl) ethyl acrylate were added, and the mixture was protected by nitrogen atmosphere and irradiated with ultraviolet light for 80 minutes, and then the excess solvent was removed by rotary evaporation to obtain fluorosilicone-modified silane.

[0060] Example 6. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0061] Compared with Example 1, this example increases the amount of mesoporous silica added in step S2;

[0062] S1. preparing a hydrophobic polyurethane emulsion;

[0063] By weight, 45 parts of polycarbonate diol were heated to 105°C, dried for 2 hours, and then 6 parts of fluorosilicone-modified silane were added thereto. After stirring and mixing for 2 hours, stirring was stopped, and after cooling to room temperature, 14.5 parts of isophorol diisocyanate and 0.8 parts of dibutyltin dilaurate were added thereto. The temperature was raised to 78°C, stirred and reacted for 1 hour, and then 3.2 parts of 2,2-dimethylol propionic acid were added thereto. The temperature was raised to 62°C, and the reaction was continued for 4 hours, and then the temperature was lowered to 35°C. After neutralization by adding 2 parts of triethylamine, 230 parts of deionized water were added, and the mixture was stirred at a high speed of 1600 rpm for 25 minutes to obtain a hydrophobic polyurethane emulsion;

[0064] S2. In parts by weight, 0.35 parts of mesoporous silica were mixed with 1 part of a hydrophobic polyurethane emulsion, and the mixture was stirred at a high speed of 1600 rpm for 25 min to obtain a hydrophobic mesoporous emulsion;

[0065] S3. Immerse the thermal insulation felt body in the hydrophobic mesoporous emulsion, evacuate the air pressure to 800Pa, immerse for 3 minutes, increase the pressure to 0.75MPa, continue immersing for 8 minutes, pull out the felt body, place it in a 115℃ environment, and dry it for 4-6 hours to obtain a hydrophobic mesoporous thermal insulation felt.

[0066] Comparative Example 1. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0067] Compared with Example 1, this example does not add fluorine-silicon-modified silane;

[0068] S1. preparing a hydrophobic polyurethane emulsion;

[0069] By weight, 45 parts of polycarbonate diol were heated to 105° C., dried for 2 hours, cooled to room temperature, 14.5 parts of isophorol diisocyanate and 0.8 parts of dibutyltin dilaurate were added thereto, the temperature was raised to 78° C., stirred for reaction for 1 hour, 3.2 parts of 2,2-dimethylolpropionic acid were added thereto, the temperature was raised to 62° C., the reaction was continued for 4 hours, the temperature was lowered to 35° C., 2 parts of triethylamine were added for neutralization, 230 parts of deionized water were added, and the mixture was stirred at a high speed of 1600 rpm for 25 minutes to obtain a hydrophobic polyurethane emulsion;

[0070] S2. In parts by weight, 0.15 parts of mesoporous silica were mixed with 1 part of a hydrophobic polyurethane emulsion, and the mixture was stirred at a high speed of 1600 rpm for 25 min to obtain a hydrophobic mesoporous emulsion;

[0071] S3. Immerse the thermal insulation felt body in the hydrophobic mesoporous emulsion, evacuate the air pressure to 800Pa, immerse for 3 minutes, increase the pressure to 0.75MPa, continue immersing for 8 minutes, pull out the felt body, place it in a 115℃ environment, and dry it for 4-6 hours to obtain a hydrophobic mesoporous thermal insulation felt.

[0072] Comparative Example 2. A process for preparing a hydrophobic mesoporous thermal insulation felt, comprising the following steps:

[0073] Compared with Example 1, mesoporous silica was not added in step S2 of this comparative example;

[0074] S1. preparing a hydrophobic polyurethane emulsion;

[0075] By weight, 45 parts of polycarbonate diol were heated to 105°C, dried for 2 hours, and then 6 parts of fluorosilicone-modified silane were added thereto. After stirring and mixing for 2 hours, stirring was stopped, and after cooling to room temperature, 14.5 parts of isophorol diisocyanate and 0.8 parts of dibutyltin dilaurate were added thereto. The temperature was raised to 78°C, stirred and reacted for 1 hour, and then 3.2 parts of 2,2-dimethylol propionic acid were added thereto. The temperature was raised to 62°C, and the reaction was continued for 4 hours, and then the temperature was lowered to 35°C. After neutralization by adding 2 parts of triethylamine, 230 parts of deionized water were added, and the mixture was stirred at a high speed of 1600 rpm for 25 minutes to obtain a hydrophobic polyurethane emulsion;

[0076] Wherein, the preparation method of fluorinated silicon-modified silane is:

[0077] a. After nitrogen was introduced into dimethyl sulfoxide for 2 hours, it was cooled to a constant temperature in an ice-water bath, 1 part of tetramethoxysilane and 0.04 parts of phosphoric acid were added thereto, mixed evenly, 6.5 parts of bis-aminopropyl polydimethylsiloxane were added thereto, the temperature was raised to 85°C, the reaction was stirred for 8 hours, and the excess solvent was removed by rotary evaporation to obtain amino-terminated silane;

[0078] b. Disperse 1 part of terminal aminosilane in DMF by weight, stir and mix evenly, add 0.05 parts of concentrated sulfuric acid thereto, continue mixing for 5 minutes, and then drop the mixture into 0.25 parts of 1,3-propanedithiol. During the addition, control the temperature of the reaction system to 4-8°C. After the addition is completed, heat to 82°C, stir and react for 4 hours, stop heating, and cool to constant temperature in an ice-water bath. Add an equal volume of deionized water to DMF, stir vigorously for 3 minutes, and let stand for stratification. After removing the aqueous phase, evaporate the remaining mixture in vacuo to constant weight to obtain terminal mercaptosilane;

[0079] c. By weight, 1 part of the terminal mercaptosilane was dispersed again in DMF, to which 0.04 parts of benzoin butyl ether and 0.28 parts of 2-(perfluorobutyl) ethyl acrylate were added, and the reaction was protected by a nitrogen atmosphere and irradiated with ultraviolet light for 80 minutes, and then the excess solvent was removed by rotary evaporation to obtain a fluorosilicone-modified silane;

[0080] S2. Immerse the thermal insulation felt body in the hydrophobic polyurethane emulsion, evacuate the air pressure to 800Pa, immerse for 3 minutes, increase the pressure to 0.75MPa, continue immersing for 8 minutes, pull out the felt body, place it in a 115℃ environment, and dry it for 4-6 hours to obtain a hydrophobic mesoporous thermal insulation felt.

[0081] Testing: The samples prepared in Examples 1-6 and Comparative Examples 1-2 were tested for thermal conductivity according to GB / T 10295;

[0082] The samples prepared in Examples 1-6 and Comparative Examples 1-2 were tested for hydrophobicity according to GB / T 10299-2011;

[0083] The compressive strength of the samples prepared in Examples 1-6 and Comparative Examples 1-2 was tested according to GB / T 34336-2017. The test results are shown in the following table;

[0084]

[0085] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A process for preparing a hydrophobic mesoporous thermal insulation felt, characterized in that: The following steps are involved: S1. preparing a hydrophobic polyurethane emulsion; The polycarbonate diol is heated to 105-110°C, dried for 1.5-2h, and then fluorosilicone-modified silane is added thereto. After stirring and mixing for 2-4h, stirring is stopped, and after cooling to room temperature, isophorol diisocyanate and dibutyltin dilaurate are added thereto. The temperature is raised to 78-82°C, and stirred for reaction for 0.5-1.5h. Then, 2,2-dimethylolpropionic acid is added thereto. The temperature is raised to 60-62°C, and the reaction is continued for 2-4h. The temperature is then lowered to 30-35°C, triethylamine is added for neutralization, and deionized water is added thereto. The mixture is stirred at a high speed of 1200-2400rpm for 15-30min to obtain a hydrophobic polyurethane emulsion. S2. The mesoporous silica was mixed with a hydrophobic polyurethane emulsion, and the mixture was stirred at a high speed of 1200-2400 rpm for 15-30 min to obtain a hydrophobic mesoporous emulsion; S3. Immerse the thermal insulation felt body in the hydrophobic mesoporous emulsion, evacuate the air pressure to 500-1000Pa, immerse for 3-5 minutes, increase the pressure to 0.5-0.8MPa, continue immersing for 5-10 minutes, pull out the felt body, place it in an environment of 105-120℃, and dry it for 4-6 hours to obtain a hydrophobic mesoporous thermal insulation felt.

2. The process for preparing a hydrophobic mesoporous thermal insulation felt according to claim 1, characterized in that: In step S1, the preparation method of the fluorosilicone-modified silane is: a. After nitrogen is passed into dimethyl sulfoxide for 0.5-4h, the mixture is cooled to a constant temperature in an ice-water bath, tetramethoxysilane and sodium hydroxide are added thereto, mixed evenly, bis-aminopropyl polydimethylsiloxane is added thereto, the temperature is raised to 85-90°C, the reaction is stirred for 4-12h, and the excess solvent is removed by rotary evaporation to obtain amino-terminated silane; b. Disperse the terminal amino silane in DMF, stir and mix evenly, add concentrated sulfuric acid thereto, continue mixing for 3-5 minutes, and then drop the mixture into 1,3-propanedithiol. During the dropwise addition, control the temperature of the reaction system to 4-15°C. After the dropwise addition is completed, heat to 78-85°C, stir and react for 1.5-5 hours, stop heating, and cool to constant temperature in an ice-water bath. Add an equal volume of deionized water to DMF, stir vigorously for 1-3 minutes, and allow to stand for stratification. After removing the aqueous phase, evaporate the remaining mixture in vacuo to constant weight to obtain terminal mercapto silane; c. The terminal mercaptosilane was dispersed again in DMF, to which benzoin butyl ether and 2-(perfluorobutyl) ethyl acrylate were added, and the mixture was protected by nitrogen atmosphere. After ultraviolet irradiation for 45-90 minutes, the excess solvent was removed by rotary evaporation to obtain fluorosilicone-modified silane.

3. The process for preparing a hydrophobic mesoporous thermal insulation felt according to claim 2, characterized in that: In step a, the mass ratio of tetramethoxysilane, sodium hydroxide and bisaminopropyl polydimethylsiloxane is 1:(0.03-0.05):(6.5-8.5) in parts by weight.

4. The process for preparing a hydrophobic mesoporous thermal insulation felt according to claim 2, characterized in that: In step b, the mass ratio of the amino-terminated silane, concentrated sulfuric acid and 1,3-propanedithiol is 1:(0.05-0.08):(0.25-0.31) in parts by weight.

5. The process for preparing a hydrophobic mesoporous thermal insulation felt according to claim 2, characterized in that: In step c, the mass ratio of the terminal mercaptosilane, benzoin butyl ether, and 2-(perfluorobutyl)ethyl acrylate is 1:(0.02-0.04):(0.28-0.36) in parts by weight.

6. The process for preparing a hydrophobic mesoporous thermal insulation felt according to claim 1, characterized in that: In step S1, the hydrophobic polyurethane emulsion is composed of 42-48 parts of polycarbonate diol, 6-10 parts of fluorosilicone-modified silane, 12-16 parts of isophorol diisocyanate, 0.2-1 parts of dibutyltin dilaurate, 3-3.5 parts of 2,2-dimethylolpropionic acid, 2-2.5 parts of triethylamine and 180-260 parts of deionized water in parts by weight; Wherein, the Mn of the polycarbonate diol is 1800-2500.

7. The process for preparing a hydrophobic mesoporous thermal insulation felt according to claim 1, characterized in that: In step S2, the mass ratio of the hydrophobic polyurethane emulsion to the mesoporous silica is 1:(0.15-0.4) in parts by weight.

8. The process for preparing a hydrophobic mesoporous thermal insulation felt according to claim 1, characterized in that: In step S3, the thermal insulation felt body is any one of glass fiber felt, basalt fiber felt, and aluminum silicate fiber felt with a thickness of 1-9 mm.

9. A hydrophobic mesoporous thermal insulation felt prepared by the preparation process according to any one of claims 1 to 8.

Images