Depolymerization of oligomers and polymers comprising cyclobutane units

Patent metadata

Field	Value
Publication number	US-12180149-B2
Application number	US-202117795397-A
Country	US
Kind code	B2
Filing date	Jan 28, 2021
Priority date	Jan 28, 2020
Publication date	Dec 31, 2024
Grant date	Dec 31, 2024

Abstract

Methods of polymer and/or oligomer depolymerization are described herein which, in some embodiments, enable facile polymer and/or oligomer decomposition under mild, non-energy intensive conditions. Briefly, a method of depolymerization comprises providing a reaction mixture comprising a transition metal catalyst, and a polymer or oligomer having a backbone including cyclobutane units, and decomposing the polymer or oligomer to provide diene monomer or alkene monomer.

First claim

The invention claimed is:

1. A method of depolymerization comprising:
providing a reaction mixture comprising a transition metal catalyst, and a polymer or oligomer having a backbone including cyclobutane units; and
depolymerizing the polymer or oligomer to provide diene monomer or alkene monomer, wherein the transition metal catalyst is of Formula (I):

wherein M is selected from the group consisting of iron, cobalt and nickel and wherein R 1 -R 7 are independently selected from the group consisting of hydrogen, alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl and heteroaryl, wherein the alkyl, heteroalkyl, cycloalkyl, heterocycloalkyl, aryl and heteroaryl are optionally substituted with one or more substituents selected from the group consisting of (C 1 -C 10 )-alkyl, (C 1 -C 10 )-alkenyl, alkoxy, halo and hydroxyl; and wherein L is selected from the group consisting of halo, N 2 , alkene/diene, carboxylate and CO;
and n is 1 or 2.

2. The method of claim 1 , wherein the diene monomer is conjugated.

3. The method of claim 1 , wherein the diene monomer is non-conjugated.

4. The method of claim 1 , wherein the diene monomer comprises a mixture of conjugated diene and non-conjugated diene.

5. The method of claim 2 , wherein the diene monomer is 1,3-butadiene or substituted 1,3-butadiene.

6. The method of claim 1 , wherein the alkene monomer is ethylene.

7. The method of claim 1 , wherein the cyclobutane units comprise 1,2-cyclobutane.

8. The method of claim 1 , wherein cyclobutane units comprise 1,3-cyclobutane.

9. The method of claim 1 , wherein the cyclobutane units comprise a mixture of 1,2-cyclobutane and 1,3-cyclobutane.

10. The method of claim 1 , wherein the cyclobutane units are separated by one or more methylenes in the polymer backbone.

11. The method of claim 1 , wherein at least 1 weight percent diene monomer or alkene monomer is recovered from decomposition of the oligomer or the polymer.

12. The method of claim 1 , wherein at least 50 percent diene monomer or alkene monomer is recovered from decomposition of the oligomer or the polymer.

13. The method of claim 1 , wherein 90-99 percent diene monomer or alkene monomer is recovered from decomposition of the oligomer or the polymer.

14. The method of claim 1 , wherein one or both chain ends of the polymer or oligomer are terminated with a functionality comprises an unsaturated moiety.

15. The method of claim 14 , wherein the unsaturated moiety is a vinyl or ally moiety.

16. The method of claim 1 , wherein diene monomer or alkene monomer is separated or collected from the reaction mixture.

17. The method of claim 16 , wherein the diene monomer or alkene monomer is separated or collected from the reaction mixture during the depolymerization reaction.

18. The method of claim 16 , wherein molecular sieves collect the diene monomer, alkene monomer or mixtures thereof.

19. The method of claim 1 further comprising reacting the diene monomer or alkene monomer to provide oligomers or polymers comprising the diene monomer or alkene monomer.

20. The method of claim 19 , wherein the diene monomer or alkene monomer are reacted in the presence of the transition metal complex of Formula (I).

Assignees

• Univ Princeton

Inventors

• Chirik Paul J
• Kennedy C Rose
• Beromi Megan Mohadjer

Classifications

• C07C2531/18

  containing nitrogen, phosphorus, arsenic or antimony · CPC title

• C07C2/46

  Catalytic processes · CPC title

• B01J2531/842

  Iron · CPC title

• B01J31/1815 Primary

  with more than one complexing nitrogen atom, e.g. bipyridyl, 2-aminopyridine · CPC title

• C07C2531/02

  containing organic compounds or metal hydrides · CPC title