Honeycomb embedded structure vacuum insulation panel and preparation method thereof
Technical Field
The invention relates to a honeycomb embedded structure vacuum insulation panel, in particular to a honeycomb embedded structure vacuum insulation panel and a preparation method thereof.
Background
Energy crisis is the present global problem, and open source throttle, improvement energy utilization rate are the important way of dealing with energy crisis. High energy consumption has become a significant bottleneck for deteriorating ecological environment and restricting economic development. Inorganic materials such as glass wool, rock wool, and ceramic fiber, and organic materials such as polystyrene and polyurethane are widely used as heat insulating materials in the fields of construction, transportation, and the like. The traditional heat insulation material has the problems that the heat insulation performance is low, and the national planning requirements of energy conservation and emission reduction can not be met. Vacuum Insulation Panels (VIPs) utilize Vacuum to achieve convection-free air, making them the most excellent insulation materials for current applications.
Chen et al, in the article, "Preparation and characterization of vacuum insulation panels with super-structured glass core material", have demonstrated that VIP prepared by dry process can effectively reduce thermal conductivity and save cost, but the dry process core material has a certain non-uniformity in structure. The invention patent 'vacuum insulation panel' (201410715032.X) proposes a vacuum insulation panel with different membrane materials compounded on the upper and lower surfaces, and the core material is glass fiber, so that the structure has the advantage that the thermal bridge phenomenon can be prevented through structural optimization. The invention 'a heat insulating board with vacuum heat insulating board' (201510010451.8) proposes a porous foam composite vacuum heat insulating board, and the structure is characterized in that the mechanical strength of VIP can be improved to a certain extent. However, most of the current VIPs have the problems that once the membrane materials are leaked, the overall structure of the VIP is bulged, and meanwhile, the fibers are adopted as the core materials, so that the overall strength of the VIP is not enough, and the application of the vacuum insulation panel in many fields is limited.
Aiming at the problems of the current VIP, the invention designs a honeycomb embedded structure vacuum insulation panel which takes a built-in vacuum insulation panel arranged in the honeycomb embedded structure as a core material, and fibers, particles or a mixture of the fibers and the particles are filled in honeycomb cells. The advantage of this structure is that the bulk strength who makes VIP improves, and the product can not take place to swell when taking place to leak gas. By optimizing the structure, the use range of the VIP can be expanded.
Disclosure of Invention
In order to overcome the problem that the existing vacuum insulation panel is expanded due to air leakage, the strength of the vacuum insulation panel is effectively improved, and the heat conductivity coefficient is reduced as far as possible. The invention provides a honeycomb embedded structure vacuum insulation panel which comprises a honeycomb structure material, an embedded material, a built-in vacuum insulation panel, a high-barrier film bag and a getter, wherein the embedded material is made of a metal material; the honeycomb structure material is a topological polygonal honeycomb type cell structure; the embedded material is formed by compounding fibers, particles or a mixed material of the fibers and the particles and is embedded in the honeycomb cell; the built-in vacuum insulation plate is positioned in the honeycomb structure material, and the periphery of the built-in vacuum insulation plate is wrapped by the honeycomb structure; the high-barrier film bag is made of an external packaging material, the honeycomb embedded structure is wrapped in the high-barrier film bag and is vacuumized, and the getter is arranged between the high-barrier film bag and the honeycomb embedded structure material.
As an improvement, the honeycomb structure is any one of aramid paper honeycomb and glass fiber honeycomb, the honeycomb cell structure can be a round, rectangular, hexagonal or special-shaped structure, and the weight ratio of the honeycomb structure material accounts for 5-50 wt% of the whole composite material.
As an improvement, when the embedded material is a mixed material of fibers and particles, the content of the fibers is 70-99.5 wt%, and the content of the particles is 0.5-30 wt%; the fiber is a combined structure of any one or more of glass fiber, ceramic fiber, rock wool fiber and mineral fiber; the particles comprise 1 to 25 weight percent of framework particles, 0.5 to 10.8 weight percent of light scattering powder and 2.0 to 6.5 weight percent of shading powder; the skeleton particles are at least one of micro silicon powder and silicon dioxide powder; the light scattering powder is a composite structure of one or more of titanium dioxide, iron oxide, aluminum oxide and carbon black, and the light shading powder is polyvinyl chloride particles with molecular weight of 35000-50000.
As an improvement, the light scattering powder is a composition of titanium dioxide and iron oxide, wherein the mass ratio of the iron oxide to the titanium dioxide is (1-3) to (0.1-1).
As an improvement, the shading powder is polycarbonate particles or a mixture of the polycarbonate particles and polyvinyl chloride particles, wherein when the shading powder is the mixture, the volume ratio of the polyvinyl chloride particles to the polycarbonate particles is (2-5): 1.
as an improvement, the built-in vacuum insulation board is placed inside the honeycomb structure material, the thickness of the built-in vacuum insulation board is 5-20mm, and the distance from the outer edge of the honeycomb structure material is 5-30 mm.
Meanwhile, the preparation method of the honeycomb embedded structure vacuum insulation panel is also provided, and the specific steps are
(1) Preparation of honeycomb embedded structure material
Weighing fiber raw materials or mixed raw materials of the fiber and the particles according to a certain proportion, adding the raw materials into a solvent for wet pulping, wherein the pulping speed is 500 plus 5000r/min, the concentration of the pulp is 0.1-1.0 wt%, setting to enable the fiber to be brittle-broken in the solution, forming short fibers with the length of 0.1-1.5mm, adjusting the pH value of the pulp to be 1.0-6.5 by using an acid-base solution, and uniformly suspending the fiber or the mixed material of the fiber and the particles in the solution;
(2) negative pressure deposition
Embedding the slurry obtained in the step (1) into a honeycomb structure material by a negative pressure deposition method, and designing different structure appearances according to the requirements of the embedded material, wherein the pressure for negative pressure deposition is set to be 0.1-0.6 MPa;
(3) preparation of honeycomb embedded structure core material
Drying the honeycomb embedded structure material, and cutting the honeycomb embedded structure material into the required core material size; taking three honeycomb embedded structure materials with equal sizes, wherein one of the three honeycomb embedded structure materials is cut to be empty, and a built-in vacuum heat insulation plate is placed in the hollow part, and the size of the cut part is equal to that of the built-in vacuum heat insulation plate; the honeycomb structure material with the built-in vacuum insulation plate is placed in the middle, and the honeycomb embedded structure material is placed on the upper surface and the lower surface of the honeycomb structure material to form the required honeycomb embedded structure core material.
(5) Preparation of honeycomb embedded structure vacuum insulation panel
Placing the honeycomb embedded structure core material into a high-barrier film bag, placing a getter, wherein the getter is positioned between the film and the honeycomb embedded structure core material, vacuumizing, and packaging to form the honeycomb embedded structure vacuum insulation panel, wherein the internal air pressure is less than or equal to 100 Pa.
Has the advantages that: the invention provides a honeycomb embedded structure vacuum insulation panel and a preparation method thereof, wherein fibers or fibers and particles are deposited inside a honeycomb cell by utilizing a wet process combined with a negative pressure deposition technology, so that the preparation of a honeycomb embedded structure material is realized; and placing the built-in vacuum insulation panel in the honeycomb embedded structure material, placing the built-in vacuum insulation panel in a high-barrier film bag, placing a getter, vacuumizing, and packaging to form the honeycomb embedded structure vacuum insulation panel.
The composite structure utilizes embedded compounding, the honeycomb embedded structure material is used as the core material, the phenomenon that the vacuum insulation panel is bulged due to the increase of the internal pressure under the air leakage condition can be effectively prevented, the strength of the vacuum insulation panel can be effectively improved by the honeycomb embedded structure core material, and meanwhile, when the external resistance membrane is prevented from air leakage by the built-in vacuum insulation panel, the heat insulation performance of the material is not invalid. The vacuum insulation panel with the structure has stable performance, low heat conductivity coefficient, long service life and good economic and social benefits, and can be widely used as insulation materials in the fields of refrigerators, buildings, deep cooling, high-speed rails and the like.
Drawings
FIG. 1 is a schematic view of the structure of the present invention.
Fig. 2 is a schematic structural diagram of an embodiment of the present invention.
In the drawings: 10 is a high-barrier film bag, 20 is a honeycomb structure material, 30 is glass wool, 40 is a getter, 50 is a built-in vacuum insulation board, and 60 is particles.
Detailed Description
The figures of the present invention are further described below in conjunction with the embodiments.
A honeycomb embedded structure vacuum insulation panel comprises a honeycomb structure material, an embedded material, a built-in vacuum insulation panel, a high-barrier film bag and a getter; the honeycomb structure material is a topological polygonal honeycomb type cell structure; the embedded material is formed by compounding fibers, particles or a mixed material of the fibers and the particles and is embedded in the honeycomb cell; the built-in vacuum insulation plate is positioned in the honeycomb structure material, and the periphery of the built-in vacuum insulation plate is wrapped by the honeycomb structure; the high-barrier film bag is made of an external packaging material, the honeycomb embedded structure is wrapped in the high-barrier film bag and is vacuumized, and the getter is arranged between the high-barrier film bag and the honeycomb embedded structure material. According to the invention, the honeycomb embedded structure is adopted to replace the traditional fiber-laminated or particle core material structure, and the vacuum insulation plate is arranged in the honeycomb embedded structure, so that the strength of the vacuum insulation plate can be effectively improved, and the material structure cannot bulge and the heat insulation performance cannot be failed even if the barrier film is air-leaked.
The honeycomb structure is any one of aramid paper honeycomb and glass fiber honeycomb, the honeycomb cell structure can be a round, rectangular, hexagonal or special-shaped structure, and the weight ratio of the honeycomb structure material accounts for 5-50 wt% of the whole composite material. The honeycomb structure is used as a framework supporting material in the project, the strength of the vacuum insulation panel can be effectively improved, the longitudinal shear modulus of the vacuum insulation panel is larger than 70MPa, the transverse shear strength of the vacuum insulation panel is larger than 50PMa, and the material is prevented from swelling when air leaks.
When the embedded material is a mixed material of fibers and particles, the content of the fibers is 70-99.5 wt%, and the content of the particles is 0.5-30 wt%; the fiber is a combined structure of any one or more of glass fiber, ceramic fiber, rock wool fiber and mineral fiber; the particles comprise 1 to 25 weight percent of framework particles, 0.5 to 10.8 weight percent of light scattering powder and 2.0 to 6.5 weight percent of shading powder; the skeleton particles are at least one of micro silicon powder and silicon dioxide powder; the light scattering powder is a composite structure of one or more of titanium dioxide, iron oxide, aluminum oxide and carbon black, and the light shading powder is polyvinyl chloride particles with molecular weight of 35000-50000.
The light scattering powder is a composition of titanium dioxide and iron oxide, wherein the mass ratio of the iron oxide to the titanium dioxide is (1-3) to (0.1-1). The shading powder is polycarbonate particles or a mixture of the polycarbonate particles and polyvinyl chloride particles, wherein when the shading powder is the mixture, the volume ratio of the polyvinyl chloride particles to the polycarbonate particles is (2-5): 1.
the embedded material is embedded into the honeycomb cell element by utilizing a wet process, so that an embedded structure can be designed according to requirements, the purpose of improving the heat preservation performance is further achieved, and meanwhile, the heat conductivity coefficient can be further reduced by doping of the light scattering powder and the shading powder.
The built-in vacuum insulation board is arranged in the honeycomb structure material, the thickness of the built-in vacuum insulation board is 5-20mm, and the distance from the built-in vacuum insulation board to the outer edge of the honeycomb structure material is 5-30 mm. The built-in vacuum heat insulation plate can ensure that the material has better heat insulation performance under the condition that the barrier film leaks, and the heat conductivity coefficient after air leakage is lower than 8 mW/m.K.
Meanwhile, the preparation method of the honeycomb embedded vacuum insulation panel comprises the specific steps of
(1) Preparation of honeycomb embedded structure material
Weighing fiber raw materials or mixed raw materials of the fiber and the particles according to a certain proportion, adding the raw materials into a solvent for wet pulping, wherein the pulping speed is 500 plus 5000r/min, the concentration of the pulp is 0.1-1.0 wt%, setting to enable the fiber to be brittle-broken in the solution, forming short fibers with the length of 0.1-1.5mm, adjusting the pH value of the pulp to be 1.0-6.5 by using an acid-base solution, and uniformly suspending the fiber or the mixed material of the fiber and the particles in the solution;
(2) negative pressure deposition
Embedding the slurry obtained in the step (1) into a honeycomb structure material by a negative pressure deposition method, and designing different structure appearances according to the requirements of the embedded material, wherein the pressure for negative pressure deposition is set to be 0.1-0.6 MPa;
(3) preparation of honeycomb embedded structure core material
Drying the honeycomb embedded structure material, and cutting the honeycomb embedded structure material into the required core material size; taking three honeycomb embedded structure materials with equal sizes, wherein one of the three honeycomb embedded structure materials is cut to be empty, and a built-in vacuum heat insulation plate is placed in the hollow part, and the size of the cut part is equal to that of the built-in vacuum heat insulation plate; the honeycomb structure material with the built-in vacuum insulation plate is placed in the middle, and the honeycomb embedded structure material is placed on the upper surface and the lower surface of the honeycomb structure material to form the required honeycomb embedded structure core material.
(6) Preparation of honeycomb embedded structure vacuum insulation panel
Placing the honeycomb embedded structure core material into a high-barrier film bag, placing a getter, wherein the getter is positioned between the film and the honeycomb embedded structure core material, vacuumizing, and packaging to form the honeycomb embedded structure vacuum insulation panel, wherein the internal air pressure is less than or equal to 100 Pa.
Example 1
The manufacturing method of the honeycomb embedded coupling structure composite material comprises the following steps:
(1) mixing the fiber 30 and the particles 40 according to a certain proportion, wherein the mass fraction ratio of the fiber to the particles is 8:2, and the fiber is glass fiber and accounts for 80 wt%; the content of the particles accounts for 20 wt%, and the particles comprise 10 wt% of silica fume, 6 wt% of iron oxide and 4 wt% of polyvinyl chloride particles.
(2) And mixing the proportioned fiber and particle mixed material with a solvent, such as water, to form a slurry, wherein the mass fraction of the fibers and the particles in the solution is 0.1%.
(3) Adjusting beating speed to 5000r/min to make the fiber brittle in the solution to form short fiber with length of 3.0mm, and using acid-base adjusting liquid such as H2SO4Adjusting the pH value of the slurry to be 6.5 with NaOH, and uniformly suspending the fiber and particle mixed material in the solution; negative pressure deposition is carried out, so that the fiber and particle mixed material is embedded into the honeycomb structure.
(4) Drying the honeycomb embedded structure material, and cutting the honeycomb embedded structure material into the size of 300mm multiplied by 5 mm; taking three honeycomb embedded structure materials with equal size, wherein one of the three honeycomb embedded structure materials is hollow, a built-in vacuum heat insulation plate with the size of 290mm multiplied by 5mm is placed in the hollow space, and the size of the hollow space is equal to that of the built-in vacuum heat insulation plate; the honeycomb structure material with the built-in vacuum insulation plate is placed in the middle, and the honeycomb embedded structure material is placed on the upper surface and the lower surface of the honeycomb structure material to form the required honeycomb embedded structure core material.
(5) Placing the honeycomb embedded structure core material into a high-barrier film bag, placing a getter, wherein the getter is positioned between the film and the honeycomb embedded structure core material, vacuumizing, and packaging to form the honeycomb embedded structure vacuum insulation panel, wherein the internal air pressure is 10 Pa.
In order to test the influence of fibers and particles with different proportions on the performance of the obtained final vacuum insulation panel, the vacuum insulation panel is prepared under the same production conditions except the step of excluding the proportions in the example 1, a sample is obtained, and the heat conductivity coefficient of the sample is measured, wherein the specific proportions are shown in the following table 1.
TABLE 1 thermal conductivity coefficient data of vacuum insulation panels measured by mixed materials with different proportions
As can be seen from the above table 1, when the fiber content is 70-99.5 wt% and the particle content is 0.5-30 wt%, the thermal conductivity of the finally obtained vacuum insulation panel is substantially 2.3-2.8kW/(m2K) is stable. Meanwhile, mechanical property experiments are carried out on the final 1-10 groups of vacuum insulation panels obtained by using the honeycomb core material, and the measured longitudinal shear modulus of the 1-10 groups is 70-95MPa, and the transverse shear strength is 51-75 PMa.
The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.