Preparation method cellulose / polyimide composite aerogels

A technology of composite airgel and polyimide, applied in the field of materials, can solve the problems of affecting the quality of polyimide airgel products, large shrinkage, and low strength of airgel skeleton, and achieves the scope of application. Environmentally friendly, Improve quality and avoid hard-to-prepare effects

Pending Publication Date: 2019-08-30
SHAANXI UNIV OF SCI & TECH
View PDF3 Cites 4 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, due to the greater flexibility of polyamic acid molecular chains, the strength of its airgel skeleton is low, resulting in a large shrinkage of polyamic acid airgel size, which seriously affects the quality of polyimide airgel products.

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
  • Preparation method cellulose / polyimide composite aerogels
  • Preparation method cellulose / polyimide composite aerogels
  • Preparation method cellulose / polyimide composite aerogels

Examples

Experimental program
Comparison scheme
Effect test

preparation example Construction

[0024] A kind of preparation method of cellulose / polyimide composite airgel of the present invention specifically comprises the following steps:

[0025] First, reacting diamine monomers and dianhydride monomers in a (strong) polar aprotic solvent to prepare a polyamic acid solution;

[0026] The specific means are as follows: ultrasonically treat single-necked flasks, beakers, molds, magnets, etc. with absolute ethanol to remove surface impurities, and dry them for later use. Put the weighed diamine in a single-necked flask with a magnet, add a strong polar aprotic solvent, and stir until the diamine is completely dissolved; slowly add the weighed dianhydride into the diamine solution, and stir at room temperature for 24 ~48h to obtain polyamic acid solution;

[0027] Secondly, the polyamic acid solution is poured into the precipitant to precipitate and dry;

[0028] The specific means are as follows: pour the polyamic acid solution into excess precipitant to precipitate, c...

Embodiment 1

[0039] Preparation of cellulose / polyimide composite airgel: First, 2.00g 4,4'-diaminodiphenyl ether (ODA), 2.18g pyromellitic anhydride (PMDA), 25mL N,N-diphenyl Polyamic acid solution was prepared from methyl formamide, and polyamic acid powder was obtained after precipitation, washing, and freeze-drying; secondly, 0.01g methylcellulose was dispersed in 10mL 70°C deionized water, and 0.2g polyamic acid was added after cooling powder, 0.1mL triethylamine, stirred to obtain a polyamic acid / methylcellulose aqueous solution, poured into a mold, degassed, frozen, and freeze-dried to obtain a polyamic acid / methylcellulose composite aerogel; finally, after Polyimide / methylcellulose composite airgel was obtained by thermal imidization treatment, and the thermal imidization process was: 120°C (0.5h) + 150°C (0.5h) + 200°C (1h) + 250°C ( 4h). The size shrinkage of the polyimide / methylcellulose composite airgel prepared in this example is significantly reduced, thereby improving the qu...

Embodiment 2

[0041] Preparation of cellulose / polyimide composite airgel: First, 2.00g 4,4'-diaminodiphenyl ether (ODA), 2.18g pyromellitic anhydride (PMDA), 25mL N,N-diphenyl Prepare polyamic acid solution with methyl formamide, and obtain polyamic acid powder after precipitation, washing, and freeze-drying; secondly, disperse 0.06g nanocellulose in 10mL 70°C deionized water, add 0.2g polyamic acid powder after cooling , 0.1mL triethylamine, stirred to obtain a polyamic acid / nanocellulose aqueous solution, poured into a mold, degassed, frozen, and freeze-dried to obtain a polyamic acid / nanocellulose composite aerogel; The polyimide / nanocellulose composite airgel was obtained by chemical treatment, and the thermal imidization process was: 120°C (0.5h) + 150°C (0.5h) + 200°C (1h) + 250°C (4h). The size shrinkage of the polyimide / methylcellulose composite airgel prepared in this example is significantly reduced, thereby improving the quality of the polyimide airgel product.

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

No PUM Login to view more

Abstract

The invention discloses a preparation method cellulose / polyimide composite aerogels, and belongs to the technical field of materials. The preparation method includes the following steps: polyamic acid is dissolved in a cellulose aqueous dispersion through a solubilizer; through freezing, drying, and thermal imidization, the cellulose / polyimide composite aerogels are obtained. The preparation method has the advantages of simpleness, high efficiency, low requirements for equipment, an extensive application scope and friendly environment. The problem that traditional polyimide type high-performance composite aerogels are difficult to prepare is effectively avoided. The obtained composite aerogels can be applied to air adsoprtion, organic substance adsorption, heat insulation materials andthe like and have great potential application value in the field of air pollution treatment, water pollution treatment, heat insulation structured materials and the like.

Description

technical field [0001] The invention belongs to the technical field of materials, and relates to the preparation of polymer airgel, in particular to a polyimide airgel / cellulose composite airgel method. Background technique [0002] Airgel is a highly dispersed solid material, mainly composed of a nanoporous network structure filled with a gaseous dispersion medium in the pores obtained by the aggregation of colloidal particles (or polymer molecules). Three-dimensional porous nanomaterials in which the liquid component is replaced by a gas while still maintaining its gel network. The special continuous three-dimensional network structure makes airgel show unique properties in thermal, mechanical, acoustic, optical, electrical, etc. and other fields have received much attention. [0003] Polyimide refers to a class of polymers containing imide rings in the molecular main chain structural unit, which has outstanding thermo-oxidative stability, dielectric properties, environm...

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): C08J9/28C08L79/08C08L1/28C08L1/02
CPCC08J9/28C08J2201/0484C08J2379/08C08J2401/02C08J2401/28
Inventor 卓龙海谢璠马聪陈珊珊蔡亚玲
Owner SHAANXI UNIV OF SCI & 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