Material with porous structure and preparation method thereof

A porous structure and compound technology, applied in the direction of silica, silicon oxide, etc., can solve the problems of colloids that cannot be reached, low thermal conductivity, cracking, etc., and achieve the effect of reducing surface tension, low thermal conductivity, and low density

Inactive Publication Date: 2008-09-24
IND TECH RES INST
View PDF0 Cites 1 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0004] However, it is currently known that when the gel is synthesized by the sol-gel method, due to the surface tension caused by the hydrophilic functional group -OH on the surface of the airgel, when it is in contact with air for ambient pressure drying (ambient pressure drying). Cracked due to huge surface tension contraction, and the dry colloid that destroys its internal network structure is broken, resulting in the colloid not being able to achieve low thermal conductivity.

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

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Material with porous structure and preparation method thereof
  • Material with porous structure and preparation method thereof
  • Material with porous structure and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0030] When the existing airgel is prepared, the surface of the colloid usually appears as a hydrophilic aerogel, as shown in the following formula (I). Therefore, once it contacts the atmosphere, it will absorb the water vapor in the atmosphere, resulting in a porous structure of the colloid. It is destroyed, and at the same time reduces the heat insulation performance of the material, making it unable to be used for a long time, without weather resistance and continuous use. And because the thermal conductivity of the airgel itself will decrease rapidly due to the high ambient temperature, it cannot be used at high temperatures.

[0031]

[0032] Generally, aerogels prepared by using silicon alkoxide or silicate, the surface functional group is mainly -OH, and this kind of hydrophilic functional group will break due to the huge surface tension contraction when it comes into contact with air. , in order to enable the drying procedure to be carried out under normal pressure...

Embodiment 1

[0040] Example 1. Preparation of Modified Porous Airgel

[0041] This example is to make an airgel heat insulating material with a nano-scale porous network structure, and the preparation process is as follows figure 2 shown. First, using the sol-gel method, after the precursor material (precursor material) is mixed with an organic solvent, an acid catalyst is added for hydrolysis reaction; then an alkali catalyst is added for condensation reaction (condensation), and a sol (sol) will be formed after the reaction. Sol refers to extremely small colloidal particles. In the sol stage, the colloidal particles will be evenly distributed in the solution. Then, the molecules in the sol will continue to undergo condensation reactions to form bonds, gradually forming a semi-solid polymer gel, and after a period of aging, the colloid will gradually form a three-dimensional network structure with stable structure.

[0042] The precursor material of this embodiment is tetraethoxysilane...

Embodiment 2

[0048] Embodiment 2, characteristic test of porous airgel

[0049] In this example, the porous aerogels before modification and after modification in Example 1 were tested for density, porosity, volume shrinkage, thermal conductivity, BET specific surface area, average pore diameter, and average pore volume, and were measured by IR The structure and composition of the porous airgel were observed with an electron microscope. Various characteristic tests of the present invention use dead volume developed in Japan as a method for analyzing and measuring the pore structure of porous materials.

[0050] The characteristics of the porous airgel before modification and after modification in Example 1 are shown in Table 1. The results show that after modification and with the increase in the number of modification times, the density of the airgel will decrease or even drop to about 0.069 (g / cm 3 ), the porosity can increase to about 97%, and the specific surface area increases, whil...

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
porosityaaaaaaaaaa
densityaaaaaaaaaa
Login to view more

Abstract

The invention provides porous material which is synthesized by alkane silica or silicate compound and organic solvent by a sol-gel process and intensified by intensifying agent. The invention also provides a method of making the porous material, which includes the following steps: (a) the mixed alkane silica or the silicate compound are synthesized by the organic solvent by the sol-gel process, and intensified by the intensifying agent. The invention makes use of the intensifying agent to replace the hydrophilic functional group with the hydrophobic functional group and can reduce the surface tension, so as to maintain the porous structure. The porous material made by the invention is characterized by low heat transfer coefficient, high porosity, high hydrophobicity, self-cleaning ability, etc.

Description

technical field [0001] The present invention relates to a porous structure material containing alkyl silane oxygen and its preparation method, especially to modify the hydrophilic functional group on the surface of the porous structure material into a hydrophobic functional group with a modifying agent, so as to reduce the surface tension, thermal conductivity and Density, and increase its porosity, making it a material with high thermal insulation properties. Background technique [0002] The porous material of silica airgel has the same chemical composition as glass. The material itself has the advantages of low density, low refractive index, high specific surface area, small pore size, and visible light range. It has obvious market value and can be widely used in Related technologies, including: colloid-derived glass blocks and optical fibers, solar storage tanks, high-temperature furnace insulation, insulation pipes, filling materials, radiant luminescence and power syst...

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): C08G77/50C01B33/14C08J9/00
Inventor 张育诚郑景亮林琨程魏得育吕世源
Owner IND TECH RES INST
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