Preparation method of silica aerogel aqueous heat-insulating coating

A technology of thermal insulation coating and silicon dioxide, applied in chemical instruments and methods, coatings, inorganic chemistry, etc., can solve the problems of uneven coating, affecting the service life of thermal insulation coatings, and inability to cross-link.

Inactive Publication Date: 2012-10-10
HENAN UNIVERSITY OF TECHNOLOGY +1
View PDF6 Cites 96 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The main grafted oxyalkyl groups or alkyl groups in the hydrophobic airgel pores, when added to the water-based coating, cannot form a uniform composite coating, and delamination occurs. After the coating dries, the coating will appear uneven and fall off. Phenomenon, affect the heat insulation effect and the service life of heat insulation coating
When the hydrophobic microspheres are added to the oil-based paint, since the surface of the microspheres is mainly an oxyalkyl group or an alkyl group, which is an inert group, it cannot have a cross-linking effect with the polymer in the oil-based paint, and the combination is not firm.
In addition, some solvents in the oily system may enter the interior of the airgel microspheres, affecting the thermal insulation performance of the entire composite coating, and also have a certain impact on the structure of the airgel microspheres
Oil-based coatings are not environmentally friendly, which is also the reason why water-based coatings are generally concerned
If the hydrophilic airgel microspheres are added to the water-based coating system, the structure of the airgel microspheres will collapse, and the prepared composite coating has no thermal insulation effect

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

[0040] (1) SiO 2 Sol preparation: Calculate the molar ratio of TEOS, absolute ethanol, and distilled water at a ratio of 1:5:4, then the masses of TEOS, absolute ethanol, and distilled water are 208.33g, 230.35g, and 72.04g, respectively , 4 ml of nitric acid (63% concentration by mass), in a water bath at 40°C for 2 hours;

[0041] (2) SiO 2 Preparation of wet gel microspheres: connect the atomization device, use a 0.2mm atomization nozzle, and the atomization pressure is 20Mpa, so that the sprayed sol is small, dense and uniform; Spray once every 10 seconds to 500ml of peanut oil in the stirring device at / min, for a total of 3-100 sprays. After the atomization is over, continue to stir for about 10min, and start to drop 2ml of ammonia water (concentration: 2%) The stirring speed is adjusted to about 500 r / m while adding ammonia water dropwise, and the stirring is continued for about 5 minutes; the obtained mixed solution of microspheres and oil is sealed with plastic wrap...

Embodiment 2

[0048] (1) Preparation of SiO2 sol: Calculate the molar ratio of orthosilyl (TMOS), absolute ethanol, and distilled water at 1:8:4, then the masses of TMOS, absolute ethanol, and distilled water are 152g, 368g, 72g, 3ml of nitric acid (63% concentration by mass), in a water bath at 60°C for 3 hours;

[0049] (2) Preparation of SiO2 wet gel microspheres: connect the atomization device, use a 0.1mm atomization nozzle, and the atomization pressure is 15Mpa, so that the sprayed sol is small, dense, and uniform, and the sol is evenly sprayed into the place In 500ml of silicone oil with a viscosity coefficient of 100μpa.s in a stirring device with a rotation speed of 700r / min, spray once every 5 seconds, the number of sprays is 50 times, continue stirring for about 10min, and start to drop 1ml of ammonia water (concentration 2%), the stirring speed was adjusted to about 400 r / m while ammonia water was added dropwise, and the stirring was continued for about 5 minutes; the mixed solu...

Embodiment 3

[0056] (1) SiO 2 Sol preparation: acidic silica sol (mass concentration 35%, Na + The concentration is less than 80ppm), absolute ethanol, and distilled water are calculated at a molar ratio of 1:2:4, and the masses of acidic silica sol, absolute ethanol, and distilled water are 171g, 92g, 72g, and 2 ml of acetic acid, respectively;

[0057] (2) SiO 2 Preparation of wet gel microspheres: connect the atomization device, use a 0.3mm atomization nozzle, and the atomization pressure is 15Mpa, so that the sprayed sol solution is small, dense, and uniform. 500ml of silicone oil with a viscosity coefficient of 200μpa.s in a stirring device per minute, spray once every 20 seconds, the number of sprays is 70 times, continue to stir for about 10min, and start to drop 5ml of ammonia water (concentration: 2%) , the stirring speed was adjusted to about 450 r / m while adding ammonia water dropwise, and the stirring was continued for about 6 minutes; the obtained mixed solution of microsphe...

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
specific surface areaaaaaaaaaaa
porosityaaaaaaaaaa
Login to view more

Abstract

The invention discloses a preparation method of a silica aerogel aqueous heat-insulating coating, and is characterized in that: prepared SiO2 microspheres are hydrophobic inside and hydrophilic outside; and the aerogel microspheres can be added into an aqueous coating carrier to prepare a good heat-insulating material. The main preparation method comprises the following steps of: before drying the prepared wet gel microspheres, performing surface modification by using an organic silane or an organic chlorosilane, so that the prepared wet gel microspheres are hydrophobic by grafting a large number of alkoxy groups or alkyl groups on the surfaces thereof, or directly preparing the hydrophobic wet gel microspheres; performing surface modification on the microspheres by using a hydrophilic silane coupling agent, and drying to obtain the SiO2 microspheres which are hydrophobic inside and hydrophilic outside; and adding the prepared microspheres into an aqueous coating for preparing the aqueous heat-insulating coating.

Description

technical field [0001] The present invention relates to a SiO with inner hydrophobic outer hydrophilic 2 Airgel microspheres are used as heat-insulating units, and water-based paint is used as a carrier to prepare a water-based heat-insulating paint. It is a composite environmental protection coating widely used in the field of heat insulation. Background technique [0002] SiO 2 Aerogel (silica aerogel) is a new type of nanoporous material with controllable structure, its porosity is as high as 80%-99%, and its specific surface area is as high as 800-1000m 2 g -1 , the typical pore size is 1-50nm, the solid-state network structure unit size is 1-20nm, and its total thermal conductivity at normal temperature and pressure is as low as 0.01W m -1 ·K -1 , is the material with the lowest thermal conductivity among solid materials. SiO 2 As a lightweight and efficient thermal insulation material, airgel has broad application prospects in aerospace, chemical industry, m...

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): C09D7/12C09D125/14C09D133/04C09D5/00C01B33/158C09C1/28C09C3/12
Inventor 何方黄渝鸿熊先文张瑞珠邹文俊彭进马秋花朱贺李荣春吴菊英
Owner HENAN UNIVERSITY OF TECHNOLOGY
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