Recovery of monomer from polyurethane materials by depolymerization

Patent metadata

Field	Value
Publication number	US-9815808-B2
Application number	US-201715442829-A
Country	US
Kind code	B2
Filing date	Feb 27, 2017
Priority date	Feb 29, 2016
Publication date	Nov 14, 2017
Grant date	Nov 14, 2017

Abstract

Methods for recovering monomers from polymers, such as polyurethanes (including thermoset polyurethanes) include heating the polymer to depolymerize the polymer and release the monomer. The monomer may be directly recovered. The polymer may include a poly(β-methyl-δ-valerolactone) (PMVL) block and the monomer recovered may be β-methyl-δ-valerolactone (MVL).

First claim

What is claimed is:

1. A method for recovering β-methyl-δ-valerolactone (MVL) from a polyurethane polymer comprising poly(β-methyl-δ-valerolactone) (PMVL) block, the method comprising:
heating the polymer to cause depolymerization and release of the MVL from the PMVL block; and
recovering the released MVL.

2. A method according to claim 1 , wherein the polyurethane polymer is a thermoset polyurethane foam.

3. A method according to claim 1 , wherein recovering the MVL comprises recovering the MVL via distillation.

4. A method according to claim 1 , wherein heating the polymer causes release of 50% or more of the MVL, and wherein recovering the released MVL comprises recovering the MVL at a purity of 90% or greater.

5. A method according to claim 1 , wherein heating the polymer comprises heating the polymer in the absence of a polymerization catalyst.

6. A method according to claim 1 , wherein heating the polyurethane polymer comprises heating the polymer in the presence of a polymerization catalyst.

7. A method according to claim 5 , wherein the polymerization catalyst is a ring opening transesterification catalyst.

8. A method according to claim 1 , wherein heating the polyurethane polymer comprises heating the polymer at a temperature in a range from 150° C. to 300° C.

9. A method according to claim 1 , wherein heating the polyurethane polymer comprises heating the polymer at a temperature in a range from 180° C. to 240° C.

10. A method according to claim 1 , wherein at least a portion of the PMVL in the polyurethane polymer comprises a PMVL block having a number average molar mass (M n ) of 0.25 kg/mol or greater.

11. A method according to claim 1 , wherein the PMVL has a 14 C/ 12 C ratio greater than zero.

12. A method for recovering β-methyl-δ-valerolactone (MVL) from a polymer comprising poly(β-methyl-δ-valerolactone) (PMVL), the method comprising:
heating the polymer to cause depolymerization and release of the MVL from the PMVL; and
recovering the released MVL.

13. A method according to claim 12 , wherein the PMVL polymer is a block copolymer comprising a PMVL block.

Assignees

• Univ Minnesota

Inventors

• Hillmyer Marc Andrew
• Panthani Tessie Rose
• Vanderlaan Marie Elizabeth
• Schneiderman Deborah Kay
• Mannion Alexander Michael Rauch
• Batiste Derek Charles
• Macosko Christopher Ward
• Wang Jay Z
• Bates Frank S

Classifications

• C07D309/30 Primary

  Oxygen atoms, e.g. delta-lactones · CPC title

• C08G81/027

  containing polyester or polycarbonate sequences · CPC title

• C08G2110/0008

  flexible · CPC title

• C08G2110/0083

  prepared using water as the sole blowing agent · CPC title

• C08G18/7671

  containing only one alkylene bisphenyl group · CPC title