Modified polyglycolic acid and molded articles for degradable downhole tools application

Patent metadata

Field	Value
Publication number	US-11827780-B2
Application number	US-202117643366-A
Country	US
Kind code	B2
Filing date	Dec 8, 2021
Priority date	Dec 8, 2021
Publication date	Nov 28, 2023
Grant date	Nov 28, 2023

Abstract

The patent application discloses a degradable polymers compounds. The polymer compounds comprises product of blends of polyglycolic acid and polylactic acid in a weight ratio of from about 99/1 to about 50/50 in mixture with a compatibilizer poly(lactic-co-glycolic acid), wherein the compounded product has a tensile strength of at least about 12,000 psi.

First claim

We claim:

1. A degradable composite, comprising:
a product of polyglycolic acid and polylactic acid in a weight ratio of from about 99/1 to about 50/50 in mixture with a compatibilizer, wherein formed polymer compound has a tensile strength of at least about 12,000 psi.

2. The degradable composition according to claim 1 , wherein the composition exhibits a weight-average molecular weight of at least 100,000 as a whole.

3. The degradable composition according to claim 1 , wherein the composition exhibits a weight-average molecular weight of at least 200,000 as a whole.

4. The degradable composition according to claim 1 , wherein the polyglycolic acid and the polylactic acid are blended in a weight ratio of from about 99/1 to about 70/30.

5. The degradable composition according to claim 1 , wherein the polyglycolic acid and the polylactic acid are blended in a weight ratio of from about 99/1 to about 90/10, and the composition is in a completely dissolved polymer-alloy state.

6. The degradable composition according to claim 1 , wherein the compatibilizer comprises a copolymer.

7. The degradable composition according to claim 1 , wherein the compatibilizer copolymer comprises poly(lactic acid-co-glycolic acid) (PLGA).

8. The degradable composition according to claim 1 , wherein the compatibilizer copolymer poly(lactic acid-co-glycolic acid) (PLGA) is ranging from 0 part to 6 part (considering PGA+PLA as 100 part).

9. The degradable composition according to claim 1 , wherein the formed product has an elongation at break of at least about 2%.

10. A process for producing a degradable composition, comprising: injection molding polyglycolic acid and polylactic acid in a weight ratio of from about 99/1 to about 50/50 in the presence of a compatibilizer, wherein the degradable composition has an elongation at break of at least about 2% and wherein the degradable composite has a tensile strength of at least about 12000 psi.

11. The process according to claim 10 , wherein blend of polyglycolic acid and polylactic acid containing the compatibilizer is injection molded.

12. The molding process according to claim 10 , wherein the injection molding is performed by means of a single-screw extruder.

13. The molding process according to claim 10 , wherein the compatibilizer comprises a copolymer.

14. The process according to claim 13 , wherein the copolymer comprises poly(lactic acid-co-glycolic acid) (PLGA).

15. An article formed from a polyglycolic acid resin composition comprising a product injection molding from a polyglycolic acid, a polylactic acid and a compatibilizer, wherein the composition has about 1 to about 30% by mass of the polylactic acid; wherein the composition is injection molded between about 230° C. and 260° C. and wherein the polyglycolic acid resin composition has a tensile strength of at least about 12000 psi.

16. The article formed from the polyglycolic acid resin composition according to claim 15 , which has an elongation at the break of at least about 2% in a stress-strain measurement.

17. The article formed from the polyglycolic acid resin composition according to claim 15 , wherein the compatibilizer comprises a copolymer poly(lactic acid-co-glycolic acid) (PLGA).

18. The article formed from the polyglycolic acid resin composition according to claim 17 , wherein the compatibilizer copolymer poly(lactic acid-co-glycolic acid) (PLGA) is ranging from 0 part to 6 part (considering PGA+PLA as 100 part, where PLA from 1 to 50 part).

Assignees

• Cnpc Usa Corp
• Beijing Huamei Inc
• China Nat Petroleum Corp

Inventors

• Xing Peixiang
• Ren Jiaxiang
• Cheng Peng
• Liu Yu

Classifications

• C08L67/04 Primary

  Polyesters derived from hydroxycarboxylic acids, e.g. lactones (C08L67/06 takes precedence) · CPC title

• C08L2205/025

  containing two or more polymers of the same hierarchy C08L, and differing only in parameters such as density, comonomer content, molecular weight, structure · CPC title

• C08L2205/03

  containing three or more polymers in a blend · CPC title

• C08G63/08 Primary

  Lactones or lactides · CPC title