Polyethylene terephthalate (PET) aerogel

Patent metadata

Field	Value
Publication number	US-12187869-B2
Application number	US-201915733653-A
Country	US
Kind code	B2
Filing date	Mar 28, 2019
Priority date	Mar 28, 2018
Publication date	Jan 7, 2025
Grant date	Jan 7, 2025

Abstract

A polyethylene terephthalate aerogel. There is provided a polyethylene terephthalate (PET) aerogel comprising a porous network of cross-linked recycled PET fibers, wherein the PET aerogel has a thermal conductivity of 0.030-0.050 W/m K. There is also provided a method of forming the PET aerogel.

First claim

The invention claimed is:

1. A polyethylene terephthalate (PET) aerogel comprising a porous network of cross-linked recycled PET fibers, wherein the PET aerogel has a thermal conductivity of 0.030-0.050 W/m K.

2. The PET aerogel according to claim 1 , wherein the recycled PET fibers comprised in the PET aerogel are obtained from PET plastic bottles.

3. The PET aerogel according to claim 1 , wherein the cross-linked recycled PET fibers comprised in the aerogel are cross-linked with a cross-linker selected from: tetraethoxysilane (TEOS), polyvinyl alcohol (PVA), glutaraldehyde (GA), methyltrimethoxysilane (MTMS), sodium silicate, bentonite, starch, nanoclay, or a combination thereof.

4. The PET aerogel according to claim 3 , wherein the cross-linker is TEOS.

5. The PET aerogel according to claim 3 , wherein the cross-linker is a combination of PVA and GA.

6. The PET aerogel according to claim 1 , wherein the PET aerogel has a density of 0.007-0.450 g/cm 3 .

7. The PET aerogel according to claim 1 , wherein the PET aerogel has a compressive Young's modulus of ≤130.0 kPa.

8. The PET aerogel according to claim 1 , wherein the PET aerogel is superhydrophobic and has a contact angle of 120-150°.

9. A method of forming the PET aerogel according to claim 1 , the method comprising:
hydrolysing recycled PET fibers to form hydrolysed recycled PET fibers, wherein the hydrolysing forms at least carboxylic groups on a surface of the hydrolysed recycled PET fibers;
cross-linking the hydrolysed recycled PET fibers with a cross-linker;
gelation of the cross-linked recycled PET fibers; and
drying to form the PET aerogel.

10. The method according to claim 9 , wherein the method further comprises sonicating the cross-linked recycled PET fibers prior to the drying.

11. The method according to claim 9 , wherein the hydrolysing comprises hydrolysing under acidic or base catalysis.

12. The method according to claim 9 , wherein the cross-linker is selected from: tetraethoxysilane (TEOS), polyvinyl alcohol (PVA), glutaraldehyde (GA), methyltrimethoxysilane (MTMS), sodium silicate, bentonite, starch, nanoclay, or a combination thereof.

13. The method according to claim 9 , wherein the method further comprises modifying the surface of the PET aerogel.

14. The method according to claim 13 , wherein the modifying comprises treating the surface of the PET aerogel with: chlorotrimethylsilane (TMCS), methoxytrimethylsilane (MTMS), 3-aminopropyltrimethoxysilane (APS), fire-retardant ceramic coating solution, or a combination thereof.

15. The method according to claim 9 , wherein the cross-linker is TEOS.

16. The method according to claim 15 , wherein the gelation comprises condensation of the cross-linked recycled PET fibers.

17. The method according to claim 15 , wherein the drying comprises aging for a pre-determined period of time.

18. The method according to claim 9 , wherein the cross-linker is PVA.

19. The method according to claim 18 , wherein the cross-linker further comprises GA.

20. The method according to claim 18 , wherein the drying comprises freezing and freeze-drying.

Assignees

• Nat Univ Singapore
• Agency Science Tech & Res

Inventors

• Duong Hai Minh
• Phan Thien Nhan
• Nguyen Thanh Xuan
• Steven Salomo
• Zhang Xiwen
• Le Duyen Khac

Classifications

• C09K3/32

  for absorbing liquids to remove pollution, e.g. oil, gasoline, fat · CPC title

• C08J2429/04

  Polyvinyl alcohol; Partially hydrolysed homopolymers or copolymers of esters of unsaturated alcohols with saturated carboxylic acids · CPC title

• C08J2367/03

  the dicarboxylic acids and dihydroxy compounds having the hydroxy and the carboxyl groups directly linked to aromatic rings · CPC title

• C08J2205/026

  Aerogel, i.e. a supercritically dried gel · CPC title

• C08J2201/0484

  the liquid phase being aqueous · CPC title