Recyclable polymers from environmentally benign building blocks

Patent metadata

Field	Value
Publication number	US-11680152-B2
Application number	US-202117321849-A
Country	US
Kind code	B2
Filing date	May 17, 2021
Priority date	Jun 2, 2020
Publication date	Jun 20, 2023
Grant date	Jun 20, 2023

Abstract

Disclosed herein are embodiments of a method for making recyclable polymers and a method for decomposing the polymers back to the monomers which can then be reused. The polymer are stable to aqueous and/or acid conditions and may have a formula IIThe method to decompose the polymer back to the monomers may comprise heating the polymer in a protic organic solvent.

First claim

We claim:

1. A method, comprising:
forming a first mixture comprising a protic organic solvent, a co-solvent, and a first polymer according to Formula II

heating the first mixture to a temperature of from 40° C. to 75° C. for 3 days;
isolating a recycled monomer compound according to Formula I from the first mixture

forming a second mixture comprising the recycled monomer compound according to Formula I, a carbonyl compound according to Formula III, and a base;

heating the second mixture to a first temperature of from 80° C. to 150° C. for a first time period;
heating the second mixture to a second temperature of from greater than 150° C. to 300° C. for a second time period; and
isolating a second polymer according to Formula II

wherein
R 1 is alkyl or OH;
R 2 is aliphatic substituted with OH;
each R 4 independently is H, C 1-6 alkyl, or phenyl;
each of R a and R b independently is Cl, OCCl 3 , OPh, or OC 1-6 alkyl;
L is C 1-6 alkyl or C 2-6 alkenyl;
each n independently is 2 to 500;
x is 1, 2, 3, 4, 5 or 6; and
y is 1 or 2.

2. The method of claim 1 , wherein the base is a hydride base.

3. The method of claim 1 , wherein the carbonyl compound is diphenyl carbonate.

4. The method of claim 1 , wherein the method further comprises introducing a vacuum while heating to the second temperature.

5. The method of claim 4 , wherein the vacuum reaches a pressure of less than 500 mtorr.

6. The method of claim 1 , wherein:
x is 1; or
y is 1; or
both x and y are 1.

7. The method of claim 1 , wherein R 2 is -L-OH.

8. The method of claim 7 , wherein the monomer compound has a structure according to Formula I-B:

9. The method of claim 1 , wherein:
R 1 is OH or CH 3 ;
L is C 1-6 alkyl;
or a combination thereof.

10. The method of claim 9 , wherein R 1 is CH 3 .

11. The method of claim 1 , wherein the monomer compound is selected from:

12. The method of claim 1 wherein the polymer is

13. The method of claim 1 , wherein:
the first time period is from greater than zero to 4 hours;
the second time period is from greater than zero to 36 hours;
or a combination thereof.

14. The method of claim 1 , wherein the protic organic solvent is an aliphatic alcohol, an aromatic alcohol, or a combination thereof.

15. The method of claim 14 , wherein:
the aliphatic alcohol is methanol, ethanol, propanol, or a combination thereof;
the aromatic alcohol is phenol;
or a combination thereof.

16. The method of claim 1 , wherein the protic organic solvent is methanol.

Assignees

• Triad Nat Security Llc

Inventors

• Sutton Andrew D
• Roland Christopher David
• Moore Cameron M

Classifications

• C08G64/403

  Recovery of the polymer · CPC title

• C08J2367/04

  Polyesters derived from hydroxy carboxylic acids, e.g. lactones (C08J2367/06 takes precedence) · CPC title

• C08J11/24 Primary

  containing hydroxyl groups · CPC title

• C08G64/0208

  saturated · CPC title

• C08G64/305 Primary

  and alcohols · CPC title