Aerogel heat insulation composite material and its preparing method

A composite material and aerogel technology, which is applied in the field of silica airgel thermal insulation composite material and its preparation, can solve the problem of difficulty in guaranteeing the high-efficiency thermal insulation effect of airgel materials, restricting large-scale or large-scale use, and reducing infrared radiation. Permeable technology and other issues, to achieve the effect of low cost, small pore size, excellent thermal insulation performance

Active Publication Date: 2006-03-22
NAT UNIV OF DEFENSE TECH
View PDF4 Cites 145 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the inherent low strength, high brittleness, and difficulty in forming of airgel materials limit the practical use of large areas or large areas.
Existing ways to solve this problem mainly contain the following classes: (1) adopt organic or inorganic adhesive to mix with airgel powder material, by compression molding (referring to No. 95197068.2 of Chinese patent " a kind of composite material containing airgel, its Preparation method and application", No. 96196879.6 "Composite material containing airgel and adhesive, its preparation method and application"), due to the addition of adhesive, although the strength of the material has been improved to a certain extent, the airgel The high-efficiency thermal insulation effect of the material is difficult to guarantee; (2) The material formed by adding an inorganic reinforcing agent (short fiber) and an infrared opacifying agent (titanium dioxide) in the sol process to form a gel and then dried by a supercritical fluid (see Chinese patent No. 97106652.3 "Modified Nano Thermal Insulation Material and Its Production Process"), its infrared opacifier is difficult to disperse evenly, and its mechanical strength is still difficult to meet the requirements of harsh environments; (3) Fiber is used as a reinforcing phase and a sol-gel process is used 1. Supercritical fluid drying process forms airgel composite material (referring to U.S. Patent No. US6068882), and described material has good thermal insulation effect and service performance, but the process comparison of depositing molecular carbon or metal on the fiber surface reduces infrared transparency Complicated; in addition, the hydrophobicity of the made material is poor, and the thermal insulation effect will be reduced due to water absorption during actual use

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0018] Ethyl orthosilicate, absolute ethanol, deionized water, and ammonia water in a molar ratio of 1:10:3:0.015 are formulated into silica sol in one step, and the volume density is 0.07g / cm2 by vacuum impregnation process. 3 In the superfine quartz fiber felt, aged at room temperature for 1 day, put into an autoclave, pre-filled with N 2 To 3MPa, heat up to 270°C at a rate of 1°C / min, keep the temperature constant after 1 hour, release the pressure slowly at a rate of 3MPa / hour, and then use N 2 Rinse the autoclave for 15 minutes, turn off the power supply, and let it cool naturally to prepare a nanoporous silica flexible thermal insulation composite material with a density of about 0.13g / cm 3 , the mechanical strength is about 0.15MPa, and the thermal conductivity at normal temperature and pressure is 0.015W / m·K (measured according to the national standard GB11108-89, the same below).

Embodiment 2

[0020] Ethyl orthosilicate, absolute ethanol, deionized water, hydrochloric acid, and ammonia water in a molar ratio of 1:10:3:0.002:0.004 are formulated into silica sol in a two-step method, and the vacuum impregnation method described in Example 1 is used. The process is impregnated, and after it gels, it is aged in ethanol solution for 2 days, put into an autoclave, and adopt the method described in Example 1 to carry out supercritical drying, and then the nanoporous silica airgel rigid thermal insulation can be obtained Composite material with a density of about 0.2 g / cm 3 , the mechanical strength is about 2MPa, and the thermal conductivity is 0.018W / m·K under normal temperature and pressure.

Embodiment 3

[0022] Ethyl orthosilicate, absolute ethanol, deionized water, and ammonia water in a molar ratio of 1:10:3:0.02 were formulated into silica sol in one step, and aged for 1 day; butyl titanate: absolute ethanol: deionized Ionized water: acetylacetone in a molar ratio of 1: 10: 3: 0.3 to prepare titanium sol, then drop the silica sol into the titanium sol under stirring, so that the ratio of raw material ethyl orthosilicate: butyl titanate is 1: 0.25 (mole ratio); according to the vacuum impregnation process described in Example 1, the impregnation is carried out, after it gels, it is aged in ethanol solution for 2 days, and then the method described in Example 1 is used for supercritical drying to obtain nanoporous SiO 2 / TiO 2 Airgel flexible thermal insulation composites.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

PropertyMeasurementUnit
densityaaaaaaaaaa
densityaaaaaaaaaa
mechanical strengthaaaaaaaaaa
Login to view more

Abstract

The heat insulating composite aerogel material consists of silica aerogel, titania as infrared opacifier and reinforcing fiber in the weight ratio of 1 to 0.1-0.7 to 0.7-3. Its preparation process includes compounding sol with silanolate, surface modifier, titanolate, alcohol solvent, acid catalyst and alkaline catalyst in certain proportion; soaking fiber felt or prefabricated fiber part in the sol; and supercritical fluid drying. The material of the present invention has high blocking effect on solid heat transfer, air heat transfer and infrared radiation heat transfer, excellent hydrophobicity, simple preparation process, low cost, mechanical strength over 2 MPa, and wide application range, and may be used in strict heat protection condition in aeronautics, astronautics, military and civil uses.

Description

technical field [0001] The invention relates to an airgel thermal insulation composite material and a preparation method thereof, in particular to a silica airgel thermal insulation composite material and a preparation method thereof. Background technique [0002] Silica airgel has the characteristics of high specific surface area, ultra-low density and nanoporous network structure, and is considered to be the best solid-state material for thermal insulation (Nicola Huling Ulrich Schubert AngewChem Int Ed.1998, 37:22-45) . However, factors such as inherent low strength, high brittleness, and difficulty in forming airgel materials limit their practical use in large areas or in large areas. Existing ways to solve this problem mainly contain the following classes: (1) adopt organic or inorganic adhesive to mix with airgel powder material, by compression molding (referring to No. 95197068.2 of Chinese patent " a kind of composite material containing airgel...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): C04B35/624C04B35/80C04B35/82C04B35/14
Inventor 冯坚张常瑞冯军宗王小东高庆福
Owner NAT UNIV OF DEFENSE TECH
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap