Flame-retardant nano-cellulose composite aerogel with oriented structure and preparation method thereof

A nanocellulose and composite aerogel technology, applied in the field of thermal insulation materials, can solve problems such as the decline of thermal insulation performance, and achieve the effects of increased carbonization, low thermal conductivity, and excellent thermal insulation performance.

Active Publication Date: 2021-04-16
UNIV OF SCI & TECH OF CHINA
View PDF11 Cites 5 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, the thermal conductivity of the airgel prepared by this method is greatly improved, resulting in a rapid decline in thermal insulation performance.

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
  • Flame-retardant nano-cellulose composite aerogel with oriented structure and preparation method thereof
  • Flame-retardant nano-cellulose composite aerogel with oriented structure and preparation method thereof
  • Flame-retardant nano-cellulose composite aerogel with oriented structure and preparation method thereof

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0031] The invention provides a method for preparing a flame-retardant nanocellulose composite airgel with an oriented structure, comprising the following steps:

[0032] S1. After mixing the nanocellulose suspension with the siloxane hydrolyzate, cross-linking through a water-soluble metal salt to obtain a composite nanocellulose hydrogel;

[0033] S2. Perform solution replacement of the composite nanocellulose hydrogel in an alcohol solution containing a carbonizing agent to obtain an alcohol gel containing a carbonizing agent; the carbonizing agent is selected from p-toluenesulfonic acid, diphenylphosphine One or more of acid and trifluoromethanesulfonic acid;

[0034] S3. Perform directional freezing on the alcohol gel containing the carbonizing agent to obtain a flame-retardant nanocellulose composite airgel with a directional structure.

[0035] The nanocellulose composite airgel prepared by the method of the present invention has good flame retardancy, the limiting oxy...

Embodiment 1

[0049] Take 1g of cellulose raw pulp, 0.015g of tetramethylpiperidine nitrogen oxide, 0.06g of sodium bromide, and 100mL of deionized water in a beaker. After mixing and stirring evenly, add 6mL of a 10% sodium hypochlorite solution by mass fraction, Stirring was continued for 5 hours; during the reaction, the pH of the system was maintained at 10.5 by dropping 0.5 mol / L sodium hydroxide solution. Subsequently, the obtained mixture was mechanically treated with a domestic mixer at a rotational speed of 1000 r / min, and washed with deionized water after 30 minutes to obtain a nanocellulose suspension.

[0050] The obtained nanocellulose suspension and the methyltrimethoxysilane hydrolyzate obtained at pH=3 were stirred and mixed in a household mixer at a speed of 1200 r / min for 10 minutes according to a mass ratio of 1:0.1, Then slowly add 10% calcium chloride solution dropwise to obtain composite nanocellulose hydrogel.

[0051] The obtained composite nanocellulose hydrogel is...

Embodiment 2

[0056] Take 1g of cellulose raw pulp, 0.015g of tetramethylpiperidine nitrogen oxide, 0.06g of sodium bromide, and 100mL of deionized water in a beaker. After mixing and stirring evenly, add 6mL of a 10% sodium hypochlorite solution by mass fraction, Stirring was continued for 5 hours; during the reaction, the pH of the system was maintained at 10.5 by dropping 0.5 mol / L sodium hydroxide solution. Subsequently, the obtained mixture was mechanically treated with a domestic mixer at a rotational speed of 1000 r / min, and washed with deionized water after 30 minutes to obtain a nanocellulose suspension.

[0057] The obtained nanocellulose suspension and the methyltrimethoxysilane hydrolyzate obtained at pH=3 were stirred and mixed in a household mixer at a speed of 1200 r / min for 10 minutes according to a mass ratio of 1:0.25, Then slowly add 10% calcium chloride solution dropwise to obtain composite nanocellulose hydrogel.

[0058] The obtained composite nanocellulose hydrogel i...

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
limiting oxygen indexaaaaaaaaaa
limiting oxygen indexaaaaaaaaaa
limiting oxygen indexaaaaaaaaaa
Login to view more

Abstract

The invention provides a flame-retardant nano-cellulose composite aerogel with an oriented structure and a preparation method of the flame-retardant nano-cellulose composite aerogel. The preparation method comprises the following steps: S1, mixing a nano-cellulose suspension with a siloxane hydrolysate, and carrying out a crosslinking reaction with a water-soluble metal salt to obtain a composite nano-cellulose hydrogel; S2, performing solution replacement on the composite nano-cellulose hydrogel in an alcoholic solution containing a carbonizing agent to obtain an alcoholic gel containing the carbonizing agent, preferably, the carbonizing agent being p-toluenesulfonic acid; and S3, carrying out directional freezing on the alcohol gel containing the carbonizing agent to obtain the flame-retardant nano-cellulose composite aerogel with a directional structure. In the preparation process, carbonizing agents such as methylbenzenesulfonic acid are added, so that the carbonizing degree of cellulose is improved, and heat and combustible volatile components are prevented from being transferred; meanwhile, siloxane is introduced in situ during preparation, so that the flame-retardant effect is further achieved. The nanocellulose composite aerogel disclosed by the invention is low in heat conductivity coefficient and excellent in heat preservation and insulation performance.

Description

technical field [0001] The invention relates to the technical field of thermal insulation materials, in particular to a flame-retardant nano-cellulose composite airgel with an oriented structure and a preparation method thereof. Background technique [0002] As one of the lightest solid materials in the world, airgel is known as the "miracle material of the 21st century" due to its porous structure. It has excellent properties such as high porosity, large specific surface area, and low bulk density. The porous structure of airgel makes it have extremely low thermal conductivity, so airgel has great application prospects in the field of thermal insulation. [0003] There are many types of aerogels, which can be divided into oxide aerogels, carbide aerogels, and polymer-based organic aerogels. Traditional carbide aerogels are generally made of non-renewable and non-biodegradable materials such as carbon nanotubes and graphene, but considering the requirements of the environme...

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): C08L1/02C08K3/36C08K3/16C08K5/42C08J9/28C08J3/24C08J3/075
CPCY02P20/54
Inventor 程旭东闫明远龚伦伦潘月磊
Owner UNIV OF SCI & TECH OF CHINA
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