IP Library › Granted Patent US 12,187,856
Granted Patent B2
US 12,187,856 · App. 17/001,338 · Granted Jan 7, 2025

Depolymerization of polymers

Inventors: Dimitris Ioannis Collias (Cincinnati, OH); Paul Zimmerman (Ann Arbor, MI); Paul Takunda Chazovachii (Ann Arbor, MI); Michael Robo (Ann Arbor, MI); Anne McNeil (Ann Arbor, MI); John McDaniel (Cincinnati, OH)
Assignee: The Procter & Gamble Company
C08J11/06C09J133/02C08J2333/02
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Quick Facts
Patent No.
US 12,187,856
App. No.
17/001,338
Granted
Jan 7, 2025
Kind
B2
Abstract

Provided herein is technology relating to depolymerization of polymers and particularly, but not exclusively, to methods and systems for de-crosslinking polyacrylate salt-based polymers and other polymers and compositions made from de-crosslinking polyacrylate salt-based polymers and other polymers.

Claims (13)

1. A method for producing polyacrylic acid (PAA) from a superabsorbent polymer (SAP); wherein said SAP is further surface-crosslinked; said method comprising adding a base and NaCl to an aqueous SAP hydrogel, and sonicating said aqueous SAP hydrogel to produce said PAA;

wherein said aqueous SAP hydrogel comprises at least 2.5% weight per volume SAP.

2. The method of claim 1 , wherein the base added to said aqueous SAP hydrogel is NaOH.

3. The method of claim 1 wherein said sonicating provides an ultrasonic frequency.

4. The method of claim 1 wherein said sonicating provides a frequency of 20 kHz.

5. The method of claim 1 wherein said method recovers at least 85% of said SAP as PAA.

6. The method of claim 1 wherein said PAA has a M w of approximately 50 to 2500 kg/mol.

7. The method of claim 1 wherein said PAA has a dispersity of approximately 1.0 to 10.0.

8. The method of claim 1 wherein the maximum specific energy of said sonicating is less than or equal to 50 MJ/kg SAP.

9. The method of claim 1 wherein said sonicating is performed for at least 1 to 25 minutes.

10. The method of claim 1 further comprising obtaining said SAP from a post-consumer source or a post-industrial source.

11. A method for producing polyacrylic acid (PAA) from a crosslinked superabsorbent polymer (SAP); the method comprising forming an aqueous SAP hydrogel comprising the crosslinked SAP, base and NaCl, and sonicating the aqueous SAP hydrogel to produce the PAA;

wherein the aqueous SAP hydrogel comprises at least 2.5% weight per volume SAP.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Oct 17, 2022
From: COLLIAS, DIMITRIS IOANNIS; MCDANIEL, JOHN
To: THE PROCTER & GAMBLE COMPANY
Reel/Frame 061439/0739 →
Continuity (2)
Provisional Application 62890880 · Aug 23, 2019
Related Publication 20210054161A1 · Feb 25, 2021
References Cited (30)
US 3677788A · Zirnite · 1972 [cited by applicant]
US 5508313A · Delgado · 1996 [cited by applicant]
US 6095996A · Steer et al. · 2000 [cited by applicant]
US 7291679B2 · Maehara et al. · 2007 [cited by applicant]
US 20030114621A1 · Kasahara et al. · 2003 [cited by applicant]
US 20050037144A1 · Cesiro et al. · 2005 [cited by applicant]
US 20050101208A1 · Heider et al. · 2005 [cited by applicant]
US 20100099781A1 · Tian · 2010 [cited by examiner]
US 20100204068A1 · Kesavan et al. · 2010 [cited by applicant]
US 20100322996A1 · Wibaux et al. · 2010 [cited by applicant]
US 20100330860A1 · Puerkner et al. · 2010 [cited by applicant]
US 20120302445A1 · Rudolph et al. · 2012 [cited by applicant]
US 20140230322A1 · Zhang et al. · 2014 [cited by applicant]
US 20200149220A1 · Konishi et al. · 2020 [cited by applicant]
US 20210054248A1 · Collias et al. · 2021 [cited by applicant]
US 20230234028A1 · Collias et al. · 2023 [cited by applicant]
CN 101781535A · 2010 [cited by applicant]
CN 110237821A · 2019 [cited by applicant]
EP 0797644A1 · 1997 [cited by applicant]
EP 3238840A1 · 2017 [cited by applicant]
JP H09249711 · 1997 [cited by examiner]
KR 20200035191A · 2020 [cited by applicant]
Ebrahimi, “Influence of Ultrasonic Parameters on the Degradation of Acrylic acid/Acrylamide copolymers based superabsorbent Hydrogels cross-linked with NMBA”, Iran Polymer J, vol. 21, No. 1, 2012, pp. 11-20 (Year: 2012). [cited by examiner]
Ebrahimi et al, “The Study of Ultrasonic Degradation of Superabsorbent Hydrogels”, Organic Chemistry International, vol. 2012, Article ID 343768, 2012, 5 pages, Hindawi Publishing Corporation (Year: 2012). [cited by examiner]
Machine translation of JPH09249711, Sasaki et al, Sep. 1997 (Year: 1997). [cited by examiner]
Non Final Office Action; U.S. Appl. No. 17/001,345 dated Dec. 5, 2022. [cited by applicant]
Notice of Allowance; U.S. Appl. No. 17/001,345 dated Feb. 1, 2023. [cited by applicant]
Notice of Allowance; U.S. Appl. No. 17/001,345 dated Mar. 8, 2023. [cited by applicant]
Chazovachii et al., “Using Adhesives to Capture Microplastics from Water”, ACS Publications, Oct. 19, 2021, pp. 1698-1704. [cited by applicant]
Francesca et al., The contribution of washing processes of synthetic clothes to microplastic pollution, Scientific Reports, Retrieved from Internet:https://www.nature.com/articles/s41598-019-43023-x, Apr. 29, 2019, 11 P… [cited by applicant]