Superfine fiber and inorganic particle composite core material heat insulation plate and preparation method thereof

Abstract

The invention provides a superfine fiber and inorganic particle composite core material thermal insulation plate and a preparation method thereof, and belongs to the technical field of novel thermal insulation materials. The preparation method comprises the following steps: preparing a composite core material base material film roll by taking superfine fibers, adhesive fibers and inorganic particles as raw materials and adopting a wet papermaking process, further irradiating the base material film roll through an electron beam accelerator, then stacking the irradiated film roll into a certain thickness, and slitting according to the required length and width, so as to obtain the composite core material. And preparing the vacuum insulated panel by a vacuum packaging process. The heat conductivity coefficient of the heat insulation plate is measured, and the measured heat conductivity coefficient is 1.697 mw / m.k.

Description

Technical Field

[0001] The present invention relates to the technical field of novel thermal insulation materials, and particularly relates to an adiabatic board with a composite core material of ultra-fine fibers and inorganic particles and a preparation method thereof. Background Art

[0002] A vacuum panel is a highly efficient thermal insulation material, which is composed of a filled core material and a vacuum protection surface layer. It can effectively avoid heat transfer caused by air convection, thereby significantly reducing the thermal conductivity. It has the advantages of a thin insulation layer, small volume, and light weight. It is widely used in refrigerators and freezers, cryogenic refrigeration, biopharmaceuticals, building energy conservation, LNG storage and transportation, and other fields. Due to its high energy efficiency characteristics, it has become one of the more advanced high-efficiency thermal insulation materials in the world. It will occupy an increasingly important position in the future thermal insulation material market.

[0003] Currently, the thermal conductivity of most VIP panels on the market is above 2 mw / m·k. For VIP vacuum panels, the so-called super-insulating materials are those with a thermal conductivity less than 2 mw / m·k. The composition of VIP vacuum panels includes a core material, a barrier film, and a getter. Among them, the core material is the skeleton of the vacuum insulation panel, which plays a role in supporting the VIP panel and ensuring its long-term service, and is also the key factor determining the insulation performance of the VIP panel. Common core materials mainly include particulate core materials, foam core materials, fiber core materials, and composite core materials, etc. Among them, the production process of particulate core materials is complex, difficult to control, has high production energy consumption, high costs, and large dust in the production process of particulate materials; foam core materials have poor flame retardancy, great safety hazards, and will release toxic gases. Currently, glass fiber core materials are the most widely used type of core materials for vacuum insulation panels. Its main production process is to beat glass microfiber cotton into pulp, and then dry and form it through a wet non-woven process. The thermal conductivity is usually about 2 - 4 mw / m·k. However, glass fiber also has the disadvantage of being not environmentally friendly. Not only will a large amount of water pollutants be generated during the production process, but it will also be inhaled into the human or animal body during use, causing great harm to human life and health.

[0004] Therefore, developing a lightweight core material with low cost, high thermal resistance, and good microstructure is the preferred core material for high-performance VIPs. For high-performance, high-insulation-capability, and low-thermal-conductivity VIPs, using a fiber core material with a finer fiber diameter is the development goal of VIPs. Summary of the Invention

[0005] The purpose of the present invention is to provide an adiabatic board with a composite core material of ultra-fine fibers and inorganic particles and a preparation method thereof to solve the above technical problems.

[0006] To achieve the above invention purpose, the present invention provides the following technical solutions: The present invention provides a method for preparing an ultrafine fiber and inorganic particle composite core insulation board, comprising the following steps: 1) Opening and defibrating ultrafine chemical fibers and binder fibers respectively to obtain defibrated ultrafine chemical fibers and defibrated binder fibers; 2) Mixing the defibrated ultrafine chemical fibers, defibrated binder fibers, inorganic particles and water to prepare a slurry; 3) Forming the slurry into a wet film by a inclined wire or cylinder former; 4) Subjecting the wet film to vacuum dewatering and drying and shaping respectively to obtain a core base film; 5) Irradiating the core base film with electron beam, and laminating the irradiated core base film to make a core; 6) Packing the laminated core obtained in step 5) into an aluminum-plastic packaging bag, adding an adsorbent, evacuating and sealing to make a composite core insulation board.

[0007] Further, the mass ratio of the ultrafine chemical fiber, binder fiber and inorganic particle is 50-85:5-10:10-40.

[0008] Further, the ultrafine chemical fiber is an ultrafine polyester fiber or a polyester sea-island fiber, and the fineness of the ultrafine chemical fiber is 0.02-0.5 D.

[0009] Further, the binder fiber is a PET / PE bicomponent composite fiber or a PET / co-PET composite fiber with a sheath-core structure, and the fineness of the binder fiber is 1.2-2 D.

[0010] Further, the inorganic particle is perlite or hollow glass microsphere.

[0011] Further, the irradiation absorption dose of the electron beam irradiation is 10-60 KGy.

[0012] Further, the mass concentration of the slurry is 0.01-0.05%.

[0013] Further, the thickness of the core base film is 150-200 μm, and the grammage is 15±2 g; The thickness of the laminated core is 0.8-1.5 cm.

[0014] The present invention also provides an ultrafine fiber and inorganic particle composite core insulation board.

[0015] The beneficial effects of the present invention: Heat transfer in the VIP core material mainly relies on the solid heat conduction of the core material itself. Superfine polyester fibers have characteristics such as high temperature resistance, high modulus, and low price. By using superfine polyester fibers to replace traditional glass fibers and making a porous membrane structure cryogenic insulation material through wet non-woven technology, the pore diameter of the core material becomes smaller, the porosity increases, it can support a larger physical space, the pore structure distribution is more uniform, the fiber contact area is significantly reduced, and at the same time, the number of microscopic layers of the core material increases, thereby reducing solid heat transfer and the thermal conductivity coefficient, which is more beneficial for improving the adiabatic performance of VIP and extending its service life. Electron beam irradiation of superfine polyester fibers can form a cross-linked network between polyester molecular chains, improve the tensile strength, and enhance the fiber stiffness, which is more beneficial for supporting the physical space and avoiding the shrinkage and collapse of the external closed film under vacuum conditions; adding inorganic particles not only has good heat insulation performance but also plays a supporting role inside the core material. The lap between superfine fibers forms a porous structure that hinders the heat conduction of the gas inside the core material and limits the movement space of the residual gas in the VIP, thus ensuring low solid heat conduction inside the core material. This is very beneficial for reducing the thermal conductivity coefficient of the VIP board. Detailed implementation mode

[0016] The present invention provides a preparation method for a composite core material heat insulation board of superfine fibers and inorganic particles, comprising the following steps: 1) Open and loosen the superfine chemical fibers and the binder fibers respectively to obtain loosened superfine chemical fibers and loosened binder fibers; 2) Mix the loosened superfine chemical fibers, the loosened binder fibers, inorganic particles and water to prepare a slurry; 3) Form the slurry into a wet film through a inclined screen or a circular screen former; 4) Subject the wet film to vacuum dehydration and drying and shaping respectively to obtain a core material base film; 5) Conduct electron beam irradiation on the core material base film, and laminate the irradiated core material base film to make a core material; 6) Put the laminated core material in step 5) into an aluminum-plastic packaging bag, add an adsorbent, evacuate and seal to make a composite core material heat insulation board.

[0017] In the present invention, the adsorbent is a conventional adsorbent, preferably CaO, MgCl2 or activated carbon.

[0018] In the present invention, the process of drying and shaping refers to the process in which the wet film after vacuum dehydration continues to remove moisture through a drying oven or a hot dryer cylinder, and the binder fibers are melted to bond the fibers contained in the wet film together, and then it is wound up to make a core material base film.

[0019] In the present invention, the mass ratio of the ultrafine chemical fiber, the binder fiber, and the inorganic particles is 50-85:5-10:10-40, preferably 60-80:5-10:10-35, and more preferably 70-80:5-10:10-25.

[0020] In the present invention, the ultrafine chemical fiber is an ultrafine polyester fiber or a polyester sea-island fiber, and the fineness of the ultrafine chemical fiber is 0.02-0.5 D, preferably 0.05-0.4 D, and more preferably 0.1-0.3 D.

[0021] In the present invention, the binder fiber is a PET / PE bicomponent composite fiber or a PET / co-PET composite fiber having a skin-core structure, and the fineness of the binder fiber is 1.2-2 D, preferably 1.3-1.8 D, and more preferably 1.4-1.6 D.

[0022] In the present invention, the inorganic particles are perlite or hollow glass microspheres, preferably hollow glass microspheres.

[0023] In the present invention, the irradiation absorption dose of the electron beam irradiation is 10-60 kGy, preferably 20-50 kGy, and more preferably 30-40 kGy.

[0024] In the present invention, the mass concentration of the slurry is 0.01-0.05%, preferably 0.02-0.04%, and more preferably 0.03-0.04%.

[0025] In the present invention, the thickness of the core material base film is 150-200 μm, preferably 160-180 μm; the grammage is 15±2 g; The thickness of the laminated core material is 0.8-1.5 cm, preferably 1 cm.

[0026] The present invention also provides an insulating board with a composite core material of ultrafine fibers and inorganic particles.

[0027] The technical solutions provided by the present invention are described in detail below in conjunction with the embodiments, but they should not be construed as limiting the protection scope of the present invention.

[0028] Example 1 An insulating board with a composite core material of ultrafine fibers and inorganic particles and a preparation method thereof. Using ultrafine fibers, binder fibers, and inorganic particles as raw materials, a composite core material base film is prepared by a wet papermaking process. Further, the base film is irradiated by an electron beam accelerator, and then the irradiated base film is laminated into a certain thickness and cut into required lengths and widths, and a vacuum insulating board is prepared by a vacuum encapsulation process.

[0029] The specific steps are as follows: 1) Open and loosen the conventional superfine polyester fiber (fineness 0.3D) and the PET / PE bicomponent composite fiber (fineness 1.8D) respectively; the processes of opening and loosening are as follows: Add the superfine polyester fiber and the PET / PE bicomponent composite bonding fiber into a high-speed stirrer, add a certain amount of water, and carry out high-speed stirring.

[0030] 2) Put the opened and loosened superfine polyester fiber, PET / PE bicomponent composite bonding fiber and perlite together into a pulp tank filled with water, stir to form a uniformly dispersed slurry (the mass concentration of the slurry is 0.05%); the mass ratio of the conventional superfine polyester fiber, the bicomponent composite bonding fiber and perlite is 70:10:20; 3) Use a inclined screen or a circular screen former to make the above-mentioned slurry into a wet film; 4) Further dehydrate the above-mentioned wet film through a vacuum dewatering tank, dry and shape it in a drying oven at 145°C, and wind it up to make a core material base film.

[0031] 5) Continuously pass the above-mentioned core material base film through the device under the electron beam accelerator in a flat and unfolded state for electron beam irradiation, and wind it up; the irradiation absorption dose is 30KGy.

[0032] 6) Stack the irradiated core material base film to make a core material with a thickness of 1 cm, a length of 40 cm and a width of 60 cm.

[0033] 7) Transfer the above-mentioned core material into an aluminum-plastic packaging bag, add an adsorbent, evacuate and seal it to make a vacuum insulation panel. Through the measurement of the thermal conductivity, the measured thermal conductivity is 1.761 mw / m·k.

[0034] Example 2

[0035] A superfine fiber and inorganic particle composite core material insulation panel and its preparation method, using superfine fiber, bonding fiber and inorganic particle as raw materials, preparing a composite core material base film by a wet papermaking process, further irradiating the base film with an electron beam accelerator, and then stacking the irradiated base film into a certain thickness and cutting it according to the required length and width, and preparing a vacuum insulation panel by a vacuum packaging process.

[0036] The specific steps are as follows: 1) Open and loosen the conventional superfine polyester fiber (fineness 0.5D) and the PET / co-PET composite fiber (fineness 2D) respectively; the processes of opening and loosening are as follows: Add the conventional superfine polyester fiber and the PET / co-PET composite fiber into a high-speed stirrer, add a certain amount of water, and carry out high-speed stirring.

[0037] 2) Put the opened and defibrated conventional superfine polyester fibers, PET / co-PET composite fibers, and hollow glass microspheres into a pulp tank filled with water, and stir to form a uniformly dispersed slurry (the mass concentration of the slurry is 0.01%); the mass ratio of the conventional superfine polyester fibers, composite binder fibers, and hollow glass microspheres is 85:5:10; 3) Use an inclined screen or a circular screen former to form the above slurry into a wet film; 4) Further dehydrate the above wet film through a vacuum dewatering tank, dry and shape it in a drying oven at 150 °C, and wind it up to make a core material base film.

[0038] 5) Continuously pass the above core material base film through the device under the electron beam accelerator in a flat and unfolded state for electron beam irradiation, and wind it up; the irradiation absorption dose is 50 KGy.

[0039] 6) Stack the irradiated core material base film to make a core material with a thickness of 1 cm, a length of 40 cm, and a width of 60 cm.

[0040] 7) Transfer the above core material into an aluminum-plastic packaging bag, add an adsorbent, evacuate and seal it to make a vacuum insulation panel. By measuring the thermal conductivity, the measured thermal conductivity is 1.722 mw / m·k.

[0041] Example 3

[0042] A superfine fiber and inorganic particle composite core material insulation panel and its preparation method, using superfine fibers, binder fibers, and inorganic particles as raw materials, preparing a composite core material base film by a wet forming process, further irradiating the base film with an electron beam accelerator, and then stacking the irradiated base film into a certain thickness and cutting it according to the required length and width, and preparing a vacuum insulation panel by a vacuum packaging process.

[0043] The specific steps are as follows: 1) Open and defibrate the polyester sea-island fiber (fineness 0.3 D) and PET / co-PET composite fiber (fineness 2 D) respectively; the opening and defibrating process is: add the polyester sea-island fiber and PET / co-PET composite fiber into a high-speed stirrer, add a certain amount of water, and carry out high-speed stirring.

[0044] 2) Put the opened and defibrated polyester sea-island fiber, PET / co-PET composite fiber, and hollow glass microspheres into a pulp tank filled with water, and stir to form a uniformly dispersed slurry (the mass concentration of the slurry is 0.03%); the mass ratio of the polyester sea-island fiber, composite binder fiber, and hollow glass microspheres is 80:5:15.

[0045] 3) Use an inclined screen or a circular screen former to form the above slurry into a wet film; 4) Further dehydrate the above-mentioned wet film in a vacuum dewatering tank, dry and shape it in a drying oven at 155°C, and then wind it up to produce the core material base film.

[0046] 5) Continuously pass the above-mentioned core material base film through the under-beam device of an electron beam accelerator in a flat and unfolded state for electron beam irradiation, and then wind it up; the irradiation absorption dose is 60 KGy.

[0047] 6) Stack the above-mentioned irradiated core material base film to produce a core material with a thickness of 1 cm, a length of 40 cm, and a width of 60 cm.

[0048] 7) Transfer the above-mentioned core material into an aluminum-plastic packaging bag, add an adsorbent, evacuate and seal it to produce a vacuum insulation panel. Through the measurement of the thermal conductivity, the measured thermal conductivity is 1.697 mw / m·k.

[0049] Example 4

[0050] A vacuum insulation panel made of a composite core material of ultrafine fibers and inorganic particles and its preparation method. Using ultrafine fibers, binder fibers and inorganic particles as raw materials, a composite core material base film is prepared by a wet papermaking process. Further irradiate the base film with an electron beam accelerator, and then stack the irradiated base film into a certain thickness and cut it according to the required length and width, and prepare a vacuum insulation panel by a vacuum packaging process.

[0051] The specific steps are as follows: 1) Open and defiberize the polyester sea-island fiber (fineness 0.3 D) and the PET / PE bicomponent composite fiber (fineness 1.8 D) respectively; the opening and defiberizing process is: add the polyester sea-island fiber and the PET / co-PET composite fiber into a high-speed stirrer, add a certain amount of water, and carry out high-speed stirring.

[0052] 2) Put the opened and defiberized polyester sea-island fiber, PET / co-PET composite fiber and perlite into a pulp tank filled with water, stir to form a uniformly dispersed slurry (the mass concentration of the slurry is 0.04%), and the mass ratio of the polyester sea-island fiber, the bicomponent composite binder fiber and the perlite is 65:5:30.

[0053] 3) Use an inclined screen or a round screen former to form the above-mentioned slurry into a wet film; 4) Further dehydrate the above-mentioned wet film in a vacuum dewatering tank, dry and shape it in a drying oven at 155°C, and then wind it up to produce the core material base film.

[0054] 5) Continuously pass the above-mentioned core material base film through the under-beam device of an electron beam accelerator in a flat and unfolded state for electron beam irradiation, and then wind it up; the irradiation absorption dose is 50 KGy.

[0055] 6) Laminate the irradiated core material base film above to make a core material with a thickness of 1 cm, a length of 40 cm, and a width of 60 cm.

[0056] 7) Transfer the above core material into an aluminum-plastic packaging bag, add an adsorbent, evacuate and seal it to make a vacuum insulation panel. By measuring the thermal conductivity, the measured thermal conductivity is 1.758 mw / m·k.

[0057] As can be seen from the above embodiments, the present invention provides a superfine fiber and inorganic particle composite core material insulation panel and its preparation method. The present invention uses superfine fibers, binder fibers, and inorganic particles as raw materials, and adopts a wet papermaking process to prepare a composite core material base film. Further, the base film is irradiated by an electron beam accelerator, and then the irradiated base film is laminated into a certain thickness and cut according to the required length and width, and a vacuum insulation panel is prepared by a vacuum packaging process. The insulation panel of the present invention is measured by the thermal conductivity, and the measured thermal conductivity is 1.697 mw / m·k. The insulation panel of the present invention can be widely applied to fields such as refrigerators, freezers, refrigerated trucks, cold storages, cold chain logistics, civil building energy conservation, and aerospace.

[0058] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A preparation method of an ultra-fine fiber and inorganic particle composite core insulation board, characterized in that, Comprising the following steps: 1) Opening and defibrating the ultrafine chemical fiber and the binder fiber respectively to obtain defibrated ultrafine chemical fiber and defibrated binder fiber; 2) Mixing the defibrated ultrafine chemical fiber, the defibrated binder fiber, inorganic particles and water to prepare a slurry; 3) Forming the slurry into a wet film through a inclined screen or a cylinder former; 4) Subjecting the wet film to vacuum dehydration and drying and shaping respectively to obtain a core material base film; 5) Conducting electron beam irradiation on the core material base film, and laminating the irradiated core material base film to make a core material; 6) Packing the laminated core material in an aluminum-plastic packaging bag, adding an adsorbent, evacuating and sealing to make a composite core material heat insulation board.

2. The preparation method of the ultrafine fiber and inorganic particle composite core insulation board according to claim 1, characterized in that, The mass ratio of the ultrafine chemical fiber, the binder fiber and the inorganic particles is 50~85:5~10:10~40.

3. The preparation method of the ultrafine fiber and inorganic particle composite core thermal insulation board according to claim 1 or 2, characterized in that, The ultrafine chemical fiber is ultrafine polyester fiber or polyester sea-island fiber, and the fineness of the ultrafine chemical fiber is 0.02~0.5 D.

4. The preparation method of the ultrafine fiber and inorganic particle composite core thermal insulation board according to claim 1 or 2, characterized in that The binder fiber is a PET / PE bicomponent composite fiber or a PET / co-PET composite fiber with a skin-core structure, and the fineness of the binder fiber is 1.2~2 D.

5. The preparation method of the ultrafine fiber and inorganic particle composite core insulation board according to claim 1 or 2, characterized in that, The inorganic particles are perlite or hollow glass microspheres.

6. The preparation method of the ultrafine fiber and inorganic particle composite core thermal insulation board according to claim 1, characterized in that, The irradiation absorption dose of the electron beam irradiation is 10~60 KGy.

7. The preparation method of the ultrafine fiber and inorganic particle composite core insulation board according to claim 1, characterized in that, The mass concentration of the slurry is 0.01~0.05%.

8. The preparation method of the ultrafine fiber and inorganic particle composite core insulation board according to claim 1, characterized in that, The thickness of the core material base film is 150~200 μm, and the grammage is 15±2 g; The thickness of the laminated core material is 0.8~1.5 cm.

9. An ultrafine fiber and inorganic particle composite core material heat insulation board prepared by the preparation method according to any one of claims 1~8.