Bionic laminated thermal insulation material

Abstract

The invention discloses a bionic laminated thermal insulation material, which imitates a multi-thin laminated and thin-layer micro-pore structure of Sequoia sempervirens bark with fire resistance, corrosion resistance and excellent thermal insulation performance. A low thermal conductivity microporous powder is used as main raw material, while reinforcing agent, plasticizer and porosity agent are added to form microporous thin-layer units, and each thin-layer unit is bonded and laminated to make a laminated thermal insulation material. The thermal conductivity of the finished products is as low as 0.02?0.05 W/m.Math.k, with good thermal insulation and mechanical properties, which can be used in a temperature range below 1000? C., with better thermal insulation and energy-saving effect and toughness than ordinary thermal insulation materials, significantly reducing the thickness of the insulation layer, and can be widely used in industrial furnaces, thermal engineering devices, insulation pipes and other fields.

Claims

1. A bionic laminated thermal insulation material comprising laminated multiple thin layers, with micropores in the thin layers, to form a structure having excellent refractory and thermal insulation properties as the bark of Sequoia sempervirens and having a low thermal conductivity and a small thickness of laminated thermal insulation material; wherein the thermal insulation material is made from a low thermal conductivity microporous powder as main raw material, into which reinforcing agent, plasticizer and porosity agent are added to form microporous thin-layer units, and the thin-layer units are bonded and laminated by adhesive to form the laminated thermal insulation material; wherein each laminate unit consists of the following weight percentages: 70-93 wt % of low thermal conductivity microporous powder, 5-20 wt % of reinforcing agent, 1-5 wt % of plasticizer, and 1-5 wt % of porosity agent; wherein the low thermal conductivity microporous powder is a mixture of one or more of silica, alumina, titanium oxide and zirconium oxide in the form of micro-scaled or nano-scaled porous powder material; wherein the reinforcing agent is a blend of one or more of alumina silicate, high alumina, mullite, alumina and zirconia inorganic fibers; wherein the plasticiser is a mixture of one or both of PEG-400 and BBP; wherein the porosity agent is a mixture of one or more of ammonium bicarbonate, silicon carbide, starch and toner; wherein the adhesive is an inorganic high temperature binder mixed with one or both of silica sol and aluminum sol, or an organic non-toxic binder mixed with one or both of polyvinylpyrrolidone and polyvinyl butyral ester; wherein the laminated thermal insulation material has a thickness of 40-50 mm and a thermal conductivity of 0.02-0.05 W/m.Math.k; and each thin layer unit has a thickness of 2-3 mm; and wherein the bionic laminated thermal insulation material is prepared by: mixing the low thermal conductivity microporous powder, the reinforcing agent, the plasticizer and the porosity agent in the above weight percentages to form a slurry; preparing thin-layer units from the slurry; bonding the thin-layer units by the adhesive to form a laminated blank; and drying the blank in a drying oven at 70-150? C. for 4-24 hours to obtain the bionic laminate insulation material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is a schematic diagram of the structure of the bionic laminated thermal insulation material of the present invention; where 1 represents the bionic laminated insulation material and 2 represents a thin layer unit.

(2) FIG. 2 is an SEM image of Sequoia sempervirens bark.

DETAILED DESCRIPTION OF EMBODIMENTS

(3) The technical solutions and effects of the present invention are further described below in conjunction with the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

Embodiment 1

(4) The bionic laminated thermal insulation material of this embodiment is prepared by weighing alumina micro powder (86% by weight, particle size 0.03 mm), alumino silicate fiber (10% by weight), starch (1% by weight) and BBP (3% by weight), putting them all into a mixer, mixing them at 1000 r/min for 30 minutes, and fully mixing them to obtain a slurry with a certain viscosity. The mixed slurry was mixed at 1000 r/min for 30 minutes to obtain a slurry with a certain viscosity, and then the thin layer unit was prepared by spin coating method with a thickness of 2 mm.

(5) The prepared thin-layer units were bonded together and a silicone adhesive was added between the units to produce the blanks. The resulting blanks were dried in a drying oven at 100? C. for 12 hours to obtain a bionic laminated insulation material 1 with a thickness of 40 mm and a laminate structure comprising 20 thin-layer units 2.

(6) The resulting product was then tested for thermal conductivity and could be used in the temperature range up to 1000? C., with a thermal conductivity as low as 0.030 W/m.Math.k at 500? C.

Embodiment 2

(7) The bionic laminated thermal insulation material of this embodiment is prepared by weighing a mixture of fumed silica and alumina micronized powder (1:1 by weight, 88% by weight, 0.04 mm particle size), mullite fiber (9% by weight), silicon carbide (1% by weight) and PEG-400 (2% by weight), putting them all into a mixer, and then mixing them thoroughly for 30 minutes at 1000 r/min to obtain a slurry with a certain viscosity. The slurry was mixed at 1000 r/min for 30 minutes to obtain a certain viscosity, and then the mixed slurry was scraped to prepare thin-layer units with a thickness of 3 mm.

(8) The prepared thin-layer units are bonded together, and polyvinylpyrrolidone binder is added between the units to produce the blanks. The resulting blanks were dried in a drying oven at 90? C. for 12 hours to obtain the bionic laminate insulation 1 with a thickness of 45 mm and a laminate structure consisting of 15 thin-layer units 2.

(9) The resulting product was then tested for thermal conductivity and could be used in the temperature range up to 1000? C., with a thermal conductivity as low as 0.044 W/m.Math.k at 500? C.

Embodiment 3

(10) The bionic laminated thermal insulation material of this embodiment is prepared by weighing alumina micronized powder (90% by weight, particle size 0.03 mm), zirconia fiber (5% by weight), silicon carbide (1% by weight) and BBP (4% by weight), putting them all into a mixer, stirring them at 1000 r/min for 30 minutes, and fully mixing them to obtain a slurry with a certain viscosity. The mixed slurry was mixed at 1000 r/min for 30 minutes to obtain a certain viscosity, and then the thin layer unit was prepared by spin coating method with a thickness of 2 mm.

(11) The prepared thin-layer units were bonded together and a silicone adhesive was added between the units to produce the blanks. The resulting blanks were dried in a drying oven at 150? C. for 12 hours to obtain the bionic laminate insulation 1 with a thickness of 40 mm and a laminate structure consisting of 20 thin-layer units 2.

(12) The resulting product was then tested for thermal conductivity and could be used in the temperature range up to 1000? C., with a thermal conductivity as low as 0.034 W/m.Math.k at 500? C.

Embodiment 4

(13) The bionic laminated thermal insulation material of this embodiment is prepared by weighing alumina micro powder (90% by weight, particle size 0.02 mm), zirconia fiber (5% by weight), carbon powder (1% by weight) and BBP (4% by weight), putting them all into a mixer, stirring them at 1000 r/min for 30 minutes, and then fully The mixed slurry was mixed at 1000 r/min for 30 minutes to obtain a certain viscosity, and then the thin layer unit was prepared by spin coating method with a thickness of 2.5 mm.

(14) The prepared thin-layer units were bonded together and a silicone adhesive was added between the units to produce the blanks. The resulting blanks were dried in a drying oven at 100? C. for 12 hours to obtain a bionic laminated insulation material 1 with a thickness of 45 mm and a laminate structure comprising 18 thin-layer units 2.

(15) The resulting product was then tested for thermal conductivity and could be used in the temperature range up to 1000? C., with a thermal conductivity as low as 0.028 W/m.Math.k at 500? C.

Embodiment 5

(16) The bionic layered insulation material of this embodiment is prepared by weighing fumed silica (90% by weight, particle size 0.03 mm), zirconia fiber (5% by weight), silicon carbide (1% by weight) and PEG-400 (4% by weight), putting them all in a mixer, mixing them at 1000 r/min for 30 Then the mixed slurry was prepared by spin coating method with the thickness of 2.5 mm.

(17) The prepared thin-layer units are bonded together and a silicone adhesive is added between the units to produce the blanks. The resulting blanks were dried in a drying oven at 100? C. for 12 hours to obtain a bionic laminated insulation material 1 with a thickness of 40 mm and a laminate structure comprising 16 thin-layer units 2.

(18) The resulting product was then tested for thermal conductivity and could be used in the temperature range up to 1000? C., with a thermal conductivity as low as 0.021 W/m.Math.k at 500? C., with excellent thermal insulation properties.

(19) The inventor made a comparative measurement of the thermal conductivity of lightweight mullite thermal insulation brick (0.8 g/cm.sup.3) at 500? C., which is 0.226 W/m-k, a difference of 10 times; if at the same temperature gradient, its thickness needs 175 mm, which is 4-5 times thicker than the thickness of the thermal insulation material of the present invention, which is prepared from low thermal conductivity microporous powder, reinforcing agent, plasticizer and porogenic agent to The bionic laminated thermal insulation material can significantly reduce the thermal conductivity of the material and improve the thermal insulation performance of the material.

(20) While certain embodiments have been described, these embodiments have been presented by way of example only, and are not intended to limit the scope of the disclosure. The attached claims and their equivalents are intended to cover all the modifications, substitutions and changes as would fall within the scope and spirit of the disclosure.