CN114318935B - High-hydrophobicity porous fiber heat insulation material and preparation method thereof - Google Patents
High-hydrophobicity porous fiber heat insulation material and preparation method thereof Download PDFInfo
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Abstract
A highly hydrophobic porous fiber heat insulation material and a preparation method thereof relate to the technical field of flexible heat insulation materials. The invention aims to solve the problem that the heat insulation performance of the traditional flexible heat insulation material is deteriorated due to poor hydrophobic performance. The high-hydrophobicity porous fiber heat insulation material consists of, by weight, 30-50 parts of inorganic fibers, 20-50 parts of a hydrophobic modifier, 40-60 parts of silica sol, 10-15 parts of a surfactant, 10-20 parts of a bonding agent, 5-15 parts of an auxiliary agent and 100-300 parts of distilled water, wherein the inorganic fibers are one or more of alumina fibers, silica fibers and mullite fibers, and the hydrophobic modifier is one or more of an organosilicon water repellent, a paraffin water repellent and talcum. The invention can obtain a high-hydrophobicity porous fiber heat insulation material and a preparation method thereof.
Description
Technical Field
The invention relates to the technical field of flexible heat insulation materials, in particular to a high-hydrophobicity porous fiber heat insulation material and a preparation method thereof.
Background
Along with the improvement of the national service life requirements of the heat insulation material, the ceramic fiber is used as a light heat insulation material, has the advantages of good heat stability, small heat conductivity, small specific heat capacity and small thermal expansion, has heat insulation and fire resistance, and is widely applied to industries such as petroleum field, metallurgical field, chemical industry field and the like.
The ceramic material has good heat insulation performance, but has strong adsorption capacity to water because of the porous structure, and the ceramic heat insulation material alone cannot have good hydrophobicity. When the heat preservation material works under the moist condition, the material absorbs water in a large area due to strong water absorption, the heat conductivity of the material is increased, the heat preservation effect is reduced, and the service life of the material is greatly reduced even if the outside of the ceramic material is protected. Therefore, in order to solve the current situation of strong water absorption capacity of the ceramic heat insulation material, it is important to improve the hydrophobic property of the ceramic heat insulation material.
Disclosure of Invention
The invention aims to solve the problem of heat insulation performance degradation caused by poor hydrophobic performance of the traditional flexible heat insulation material, and provides a high-hydrophobic porous fiber heat insulation material and a preparation method thereof.
The high-hydrophobicity porous fiber heat insulation material consists of, by weight, 30-50 parts of inorganic fibers, 20-50 parts of a hydrophobic modifier, 40-60 parts of silica sol, 10-15 parts of a surfactant, 10-20 parts of a bonding agent, 5-15 parts of an auxiliary agent and 100-300 parts of distilled water, wherein the inorganic fibers are one or more of alumina fibers, silica fibers and mullite fibers, and the hydrophobic modifier is one or more of an organosilicon water repellent, a paraffin water repellent and talcum.
The preparation method of the highly hydrophobic porous fiber heat insulation material comprises the following steps:
cutting 30-50 parts of inorganic fibers according to the length-diameter ratio of 10-20, and then placing the inorganic fibers in an oven for preheating for 12-15 hours to obtain preheated inorganic fibers; adding preheated inorganic fibers and 40-60 parts of silica sol into 100-300 parts of distilled water, magnetically stirring for 20-30 min, then adding 20-50 parts of hydrophobic modifier, 10-15 parts of surfactant, 10-20 parts of bonding agent and 5-15 parts of auxiliary agent, stirring for 30-60 min at 50-70 ℃, placing in ultrasonic equipment after stirring, carrying out ultrasonic treatment for 1-2 h, placing in suction filtration equipment after ultrasonic treatment, carrying out suction filtration for 20-30 min, and standing for 1-2 h to obtain a preformed felt; and (3) placing the preformed felt body into an oven, firstly preserving heat for 1-2 hours at the temperature of 50-70 ℃, then preserving heat for 3-4 hours at the temperature of 70-90 ℃, then preserving heat for 2-3 hours at the temperature of 110-130 ℃, and finally cooling to room temperature to obtain the high-hydrophobicity porous fiber heat insulation material.
The invention has the beneficial effects that:
according to the preparation method of the high-hydrophobicity porous fiber heat-insulating material, the inorganic fiber and the hydrophobic modifier are used as main raw materials, the inorganic fiber is added to remarkably improve the heat-resistant temperature of the heat-insulating material, and the heat-insulating material prepared from the aluminum oxide fiber and the silicon oxide fiber has the highest use temperature of 1000 ℃; the hydrophobic modifier is added to obviously improve the hydrophobic property of the heat insulation material; the silica sol is used as a solvent of the material, and the silane coupling agent is added mainly for promoting the grafting of the hydrophobic modifier on the surface of the fiber, so that the grafting rate is improved; the addition of the binding agent and the auxiliary agent can promote the formation of a fiber skeleton, increase the grafting area of the hydrophobic modifier and improve the hydrophobic performance.The high-hydrophobicity porous fiber heat insulation material prepared by the invention has good heat insulation performance and high hydrophobicity. The maximum use temperature of the flexible heat insulation material is 1000 ℃, and the moisture permeability coefficient of the heat insulation material is 4.7X10 after the hydrophobic modifier is added -11 ～5.5×10 -11 g/(mS.Pa), wet resistance factor of 1.70X10 4 ～1.98×10 4 The hydrophobicity rate is more than or equal to 99 percent.
The invention can obtain a high-hydrophobicity porous fiber heat insulation material and a preparation method thereof.
Drawings
Fig. 1 is an SEM image of the highly hydrophobic porous fibrous insulation material prepared according to the present invention in the planar direction.
Fig. 2 is a hydrophobic image of a highly hydrophobic porous fibrous insulation material prepared in accordance with the present invention.
Detailed Description
The first embodiment is as follows: the high-hydrophobicity porous fiber heat insulation material consists of, by weight, 30-50 parts of inorganic fibers, 20-50 parts of a hydrophobic modifier, 40-60 parts of silica sol, 10-15 parts of a surfactant, 10-20 parts of a binding agent, 5-15 parts of an auxiliary agent and 100-300 parts of distilled water, wherein the inorganic fibers are one or more of alumina fibers, silica fibers and mullite fibers, and the hydrophobic modifier is one or more of an organosilicon water repellent, a paraffin water repellent and talcum.
The second embodiment is as follows: the present embodiment differs from the specific embodiment in that: the surfactant is a silane coupling agent, the bonding agent is one or two of starch and polyethylene oxide, and the auxiliary agent is one or more of polysiloxane, cellulose and amide.
The other steps are the same as in the first embodiment.
And a third specific embodiment: the present embodiment differs from the first or second embodiment in that: the diameter of the inorganic fiber is smaller than 4 mu m.
Other steps are the same as those of the first or second embodiment.
The specific embodiment IV is as follows: the preparation method of the high-hydrophobicity porous fiber heat insulation material comprises the following steps:
cutting 30-50 parts of inorganic fibers according to the length-diameter ratio of 10-20, and then placing the inorganic fibers in an oven for preheating for 12-15 hours to obtain preheated inorganic fibers; adding preheated inorganic fibers and 40-60 parts of silica sol into 100-300 parts of distilled water, magnetically stirring for 20-30 min, then adding 20-50 parts of hydrophobic modifier, 10-15 parts of surfactant, 10-20 parts of bonding agent and 5-15 parts of auxiliary agent, stirring for 30-60 min at 50-70 ℃, placing in ultrasonic equipment after stirring, carrying out ultrasonic treatment for 1-2 h, placing in suction filtration equipment after ultrasonic treatment, carrying out suction filtration for 20-30 min, and standing for 1-2 h to obtain a preformed felt; and (3) placing the preformed felt body into an oven, firstly preserving heat for 1-2 hours at the temperature of 50-70 ℃, then preserving heat for 3-4 hours at the temperature of 70-90 ℃, then preserving heat for 2-3 hours at the temperature of 110-130 ℃, and finally cooling to room temperature to obtain the high-hydrophobicity porous fiber heat insulation material.
Fifth embodiment: the fourth difference between this embodiment and the specific embodiment is that: the inorganic fiber is one or more of alumina fiber, silica fiber and mullite fiber, and the diameter of the inorganic fiber is smaller than 4 mu m; the hydrophobic modifier is one or more of organosilicon water repellent, paraffin water repellent and talcum.
The addition of inorganic fibers can significantly improve the heat-resistant temperature of the heat-insulating material, and the heat-insulating material prepared by using aluminum oxide fibers and silicon oxide fibers has the highest use temperature of 1000 ℃.
The hydrophobic modifier is added to obviously improve the hydrophobic property of the heat insulation material.
The other steps are the same as those of the fourth embodiment.
Specific embodiment six: the fourth or fifth difference between this embodiment and the embodiment is that: the surfactant is a silane coupling agent, the bonding agent is one or two of starch and polyethylene oxide, and the auxiliary agent is one or more of polysiloxane, cellulose and amide.
The silane coupling agent is mainly added to promote the grafting of the hydrophobic modifier on the fiber surface and improve the grafting rate; the addition of the binding agent and the auxiliary agent can promote the formation of a fiber skeleton, increase the grafting area of the hydrophobic modifier and improve the hydrophobic performance.
The other steps are the same as those of the fourth or fifth embodiment.
Seventh embodiment: the fourth to sixth embodiments are different from the present embodiment in that: cutting 30-50 parts of inorganic fiber according to the length-diameter ratio of 10-20, then placing the inorganic fiber in an oven, and preheating the inorganic fiber for 12-15 hours at the temperature of 50-70 ℃ to obtain the preheated inorganic fiber.
The other steps are the same as those of the fourth to sixth embodiments.
Eighth embodiment: one of the differences between the present embodiment and the fourth to seventh embodiments is that: adding the preheated inorganic fiber and 40-60 parts of silica sol into 100-300 parts of distilled water, magnetically stirring for 20-30 min at a stirring speed of 300-400 rpm, then adding 20-50 parts of hydrophobic modifier, 10-15 parts of surfactant, 10-20 parts of bonding agent and 5-15 parts of auxiliary agent, and stirring for 30-60 min at a stirring speed of 250-300 rpm under the temperature condition of 50-70 ℃.
The other steps are the same as those of the fourth to seventh embodiments.
Detailed description nine: the fourth to eighth differences between the present embodiment and the specific embodiment are: after stirring, placing the mixture in ultrasonic equipment, and carrying out ultrasonic treatment for 1-2 h at the frequency of 20-25 kHz.
The other steps are the same as those of the fourth to eighth embodiments.
Detailed description ten: the present embodiment differs from the fourth to ninth embodiments in that: and after the ultrasonic treatment is finished, placing the mixture into a suction filtration device, performing suction filtration for 20-30 min under the suction filtration pressure of 90-120 kPa, and standing for 1-2 h to obtain the preformed felt body.
The other steps are the same as those of the embodiments four to nine.
The following examples are used to verify the benefits of the present invention:
example 1: the preparation method of the highly hydrophobic porous fiber heat insulation material comprises the following steps:
cutting 20 parts of aluminum oxide fibers and 10 parts of silicon oxide fibers according to an aspect ratio of 10-20 (length of 40-60 mu m and diameter of 3-4 mu m), then placing the cut aluminum oxide fibers and the cut silicon oxide fibers in an oven, and preheating the cut aluminum oxide fibers and the cut silicon oxide fibers for 14 hours at a temperature of 60 ℃ to obtain preheated inorganic fibers; adding the preheated inorganic fiber and 40 parts of silica sol into 150 parts of distilled water, magnetically stirring at a stirring speed of 300rpm for 30min until the mixed solution is uniform, then adding 20 parts of organic silicon water repellent, 10 parts of silane coupling agent, 10 parts of starch and 5 parts of polysiloxane, stirring at a stirring speed of 250rpm for 60min at a temperature of 60 ℃ so as to uniformly mix the solution, placing the solution in ultrasonic equipment after stirring is finished, and carrying out ultrasonic treatment at a frequency of 20kHz for 1-2 h to increase the grafting proportion of the organic silicon water repellent on the surface of the fiber; continuously stirring until the mixture is clear, putting the mixture into a suction filtration device, performing suction filtration for 20min under the suction filtration pressure of 110kPa, and standing for 1.5h to obtain a preformed felt; and (3) placing the preformed felt body into an oven, firstly preserving heat for 2 hours at the temperature of 70 ℃, then preserving heat for 4 hours at the temperature of 90 ℃, then preserving heat for 3 hours at the temperature of 120 ℃, and finally cooling to room temperature to obtain the high-hydrophobicity porous fiber heat insulation material.
Fig. 1 is an SEM image of the highly hydrophobic porous fiber thermal insulation material prepared in this example in the plane direction, as shown in fig. 1, in which the modified material is coated on the fiber surface, which indicates that the hydrophobic modifier is successfully grafted on the fiber surface.
Fig. 2 is a hydrophobic image of the highly hydrophobic porous fibrous insulation material prepared in this example, and as shown in fig. 2, the highly hydrophobic porous fibrous insulation material macroscopically has a remarkable hydrophobic property.
Example 2:
25 parts of alumina fiber, 10 parts of silica fiber, 30 parts of organosilicon water repellent, 45 parts of silica sol, 10 parts of silane coupling agent, 15 parts of starch, 10 parts of polysiloxane and 150 parts of distilled water. The specific preparation method is the same as that of example 1, and the high-hydrophobicity porous fiber heat insulation material prepared according to the proportion has the hydrophobicity of 99.2%.
Example 3:
30 parts of alumina fiber, 10 parts of silica fiber, 35 parts of organosilicon water repellent, 50 parts of silica sol, 12 parts of silane coupling agent, 15 parts of starch, 10 parts of polysiloxane and 150 parts of distilled water. The specific preparation method is the same as that of example 1, and the high-hydrophobicity porous fiber heat insulation material prepared according to the proportion has the hydrophobicity of 99.3 percent.
Example 4:
30 parts of alumina fiber, 20 parts of silica fiber, 50 parts of organosilicon water repellent, 60 parts of silica sol, 15 parts of silane coupling agent, 20 parts of starch, 15 parts of polysiloxane and 150 parts of distilled water. The specific preparation method is the same as that of example 1, and the high-hydrophobicity porous fiber heat insulation material prepared according to the proportion has the hydrophobicity of 99.5%.
The detection method comprises the following steps: the prepared high-hydrophobicity porous fiber heat insulation material is subjected to the following performance test:
(1) Moisture permeability test:
the moisture permeability test was performed with reference to standard GB/T17146-2015.
(2) Hydrophobicity performance test:
the hydrophobicity test was performed with reference to standard GB/T10299-2011.
Table 1 shows the results of performance tests of the highly hydrophobic porous fibrous insulation materials prepared in examples 1-4;
TABLE 1
As can be seen from the performance test results, the high-hydrophobicity porous fiber heat insulation material prepared by the invention has excellent high-temperature resistance (the highest use temperature is 1000 ℃) and hydrophobicity, while the common high-temperature resistance of the traditional flexible heat insulation material is 800 ℃, the hydrophobicity is more than or equal to 98%, which is substantially lower than that of the high-hydrophobicity porous fiber heat insulation material prepared by the invention, so that the traditional flexible heat insulation material cannot have good high-temperature resistance and hydrophobicity.
Claims (6)
1. The high-hydrophobicity porous fiber heat insulation material is characterized by comprising, by weight, 30-50 parts of inorganic fibers, 20-50 parts of a hydrophobic modifier, 40-60 parts of silica sol, 10-15 parts of a surfactant, 10-20 parts of a binding agent, 5-15 parts of an auxiliary agent and 100-300 parts of distilled water, wherein the inorganic fibers are one or more of alumina fibers, silica fibers and mullite fibers, and the diameter of the inorganic fibers is smaller than 4 mu m; the hydrophobic modifier is one or more of organosilicon water repellent, paraffin water repellent and talcum, the surfactant is silane coupling agent, the bonding agent is one or two of starch and polyethylene oxide, and the auxiliary agent is one or more of polysiloxane, cellulose and amide.
2. The method for preparing the highly hydrophobic porous fiber heat insulation material according to claim 1, which is characterized by comprising the following steps:
cutting 30-50 parts of inorganic fibers according to the length-diameter ratio of 10-20, and then placing the inorganic fibers in an oven for preheating for 12-15 hours to obtain preheated inorganic fibers; adding preheated inorganic fibers and 40-60 parts of silica sol into 100-300 parts of distilled water, magnetically stirring for 20-30 min, then adding 20-50 parts of hydrophobic modifier, 10-15 parts of surfactant, 10-20 parts of bonding agent and 5-15 parts of auxiliary agent, stirring for 30-60 min at 50-70 ℃, placing in ultrasonic equipment after stirring, carrying out ultrasonic treatment for 1-2 h, placing in suction filtration equipment after ultrasonic treatment, carrying out suction filtration for 20-30 min, and standing for 1-2 h to obtain a preformed felt; placing the preformed felt body into a baking oven, firstly preserving heat for 1-2 h at 50-70 ℃, then preserving heat for 3-4 h at 70-90 ℃, then preserving heat for 2-3 h at 110-130 ℃, and finally cooling to room temperature to obtain the highly hydrophobic porous fiber heat insulation material;
the inorganic fiber is one or more of alumina fiber, silica fiber and mullite fiber, and the diameter of the inorganic fiber is smaller than 4 mu m; the hydrophobic modifier is one or more of organosilicon water repellent, paraffin water repellent and talcum; the surfactant is a silane coupling agent, the bonding agent is one or two of starch and polyethylene oxide, and the auxiliary agent is one or more of polysiloxane, cellulose and amide.
3. The method for preparing the highly hydrophobic porous fiber heat insulation material according to claim 2, which is characterized in that 30-50 parts of inorganic fibers are cut according to the length-diameter ratio of 10-20, and then are placed in an oven to be preheated for 12-15 hours at the temperature of 50-70 ℃ to obtain the preheated inorganic fibers.
4. A method for preparing a highly hydrophobic porous fibrous insulation material according to claim 2 or 3, characterized in that the preheated inorganic fibers and 40-60 parts of silica sol are added into 100-300 parts of distilled water, magnetically stirred for 20-30 min at a stirring speed of 300-400 rpm, then 20-50 parts of hydrophobic modifier, 10-15 parts of surfactant, 10-20 parts of binder and 5-15 parts of auxiliary agent are added, and stirred for 30-60 min at a stirring speed of 250-300 rpm under a temperature condition of 50-70 ℃.
5. The method for preparing a highly hydrophobic porous fibrous insulation material according to claim 2, wherein the material is placed in an ultrasonic apparatus after the stirring is completed and subjected to ultrasonic treatment at a frequency of 20 to 25kHz for 1 to 2 hours.
6. The method for preparing the highly hydrophobic porous fiber heat insulation material according to claim 2 or 5, wherein after the ultrasonic treatment is finished, the porous fiber heat insulation material is placed into a suction filtration device, is subjected to suction filtration for 20-30 min under a suction filtration pressure of 90-120 kPa, and is kept stand for 1-2 h, so that a preformed felt body is obtained.
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