Fiber and silicon dioxide aerogel composite heat insulation material and preparation method thereof

Abstract

The invention discloses a fiber and silicon dioxide aerogel composite heat insulation material and a preparation method thereof. The fiber and silicon dioxide aerogel composite heat insulation material has thermal conductivity of 0.020 to 0.040W / m.K, porosity of 80 to 90 percent, density of 0.10 to 0.18g / cm<3>, a specific surface area of 800 to 1,000m<2> / g, a hydrophobic angle of 120 to 170 degrees and an aperture distribution of 2 to 50nm. According to the prepared heat insulation material, the thermal property of aerogel is maximally reserved, the mechanical performance of the aerogel is improved, the material has certain strength and toughness, the compressive strength of the material is 0.3 to 5MPa, and the bending strength is 0.5 to 1.5Mpa. A preparation process is simple, short in period, low in equipment cost and safe in production, and the prepared material has high heat insulation performance, has the advantages of low thermal conductivity, low density, environment friendliness, safety, nontoxicity, flame retardancy, anticorrosion and the like compared with an ordinary inorganic heat-preservation material, and can be applied to a heat insulation material for pipeline transportation, a firefighting material and the like.

Description

technical field [0001] The invention relates to a fiber composite airgel heat insulation material and its preparation method, in particular to a separate hydrolysis process for the fiber pretreatment sol, which is obtained by the acid-base two-step sol-gel method and dried at normal pressure. The silica airgel material is used in the field of heat insulation materials. Background technique [0002] Silica airgel is a lightweight nanoporous amorphous solid material with excellent properties, composed of SiO 2 It is composed of network skeleton and gas filled in nanopores. Its porosity can be as high as 80-99.8%, the typical size of the pores is 1-100nm, and the specific surface area is 200-1000m 2 / g, the density can be as low as 0.003g / cm 3 , the thermal conductivity at room temperature can be as low as 0.012w / (m K), and its unique three-dimensional network structure, extremely low density and thermal conductivity have broad applications in thermal insulation, light condu...

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Problems solved by technology

In the publication number CN1636917A, the inventor used the hollow secondary particles formed by ultrafine diameter xonotlite fibers as a hard support skeleton to form a composite material with silica aerogel, and poured the sol into the porous hard In the calcium stone structure, the silica airgel composite material prepared by this method has good thermal insulation performance, but the preparation process is relatively complicated

[0009] In the patent CN101318659A, a method for preparing silica airgel composite materials by normal pressure drying is mentioned, wherein the reinforcing body is one or both of fiber body and polyurethane soft foam, and the prepared material can be applied to construction Thermal insulation, sound insulation, industrial pipeline transportation, etc., but the polyurethane soft foam is a flammable material, resulting in poor fire safety performance of the material

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