Vinyl alcohol polymer and production method thereof, additive for drilling mud, drilling mud, additive for drilling cement slurry, and drilling cement slurry

Patent metadata

Field	Value
Publication number	US-2016229936-A1
Application number	US-201415021872-A
Country	US
Kind code	A1
Filing date	Sep 11, 2014
Priority date	Sep 13, 2013
Publication date	Aug 11, 2016
Grant date	—

Abstract

Provided by the present invention is a vinyl alcohol polymer crosslinked by a structure represented by the following formula (1) and/or a disulfide structure, in which the vinyl alcohol polymer is not completely dissolved in a mixture prepared by: adding the vinyl alcohol polymer to water so as to give a concentration of 4% by mass; and stirring at 95° C. for 3 hrs. in the formula (1), R 1 , R 2 and R 3 each independently represent a hydrogen atom or a substituted or unsubstituted hydrocarbon group having 8 or less carbon atoms. Also provided include an additive for a drilling mud containing the vinyl alcohol polymer, a drilling mud containing the vinyl alcohol polymer as an additive, an additive for a drilling cement slurry containing the vinyl alcohol polymer, and a drilling cement slurry containing the vinyl alcohol polymer as an additive.

First claim

1 . A vinyl alcohol polymer crosslinked by a structure represented by formula (1), a disulfide structure or a combination thereof, wherein the vinyl alcohol polymer is not completely dissolved in a mixture prepared by: adding the vinyl alcohol polymer to water so as to give a concentration of 4% by mass; and stirring at 95° C. for 3 Ins,

wherein, R 1 , R 2 and R 3 each independently represent a hydrogen atom, or a substituted or unsubstituted hydrocarbon group having 8 or less carbon atoms.

2 . The vinyl alcohol polymer according to claim 1 , which is in a powdery form.

3 . The vinyl alcohol polymer according to claim 2 , which passes through a 10-mesh sieve according to JIS.

4 . The vinyl alcohol polymer according to claim 1 , which is the vinyl alcohol polymer crosslinked by the structure represented by the formula (1), wherein the structure represented by the formula (1) is formed by a reaction of an epoxy group and a mercapto group.

5 . The vinyl alcohol polymer according to claim 1 , which is the vinyl alcohol polymer crosslinked by the disulfide structure, wherein the disulfide structure is formed by a coupling reaction of mercapto groups.

6 . A production method of the vinyl alcohol polymer according to claim 4 , wherein, the method comprises a reacting step of a first vinyl alcohol polymer comprising an epoxy group on a side chain thereof with a first compound comprising at least two mercapto groups per molecule.

7 . A production method of the vinyl alcohol polymer according to claim 4 , wherein, the method comprises a reacting step of a second vinyl alcohol polymer comprising a mercapto group on a side chain thereof with a second compound comprising at least two epoxy groups per molecule.

8 . A production method of the vinyl alcohol polymer according to claim 5 , wherein, the method comprises a reacting step of second vinyl alcohol polymers comprising a mercapto group on a side chain thereof with one another.

9 . The production method of the vinyl alcohol polymer according to claim 6 , wherein in the reacting, a first vinyl ester polymer comprising an epoxy group on a side chain thereof is saponified in the presence of the first compound by using an alkali catalyst so as to allow a saponification reaction in a vinyl ester unit and a reaction of an epoxy group and a mercapto group to concomitantly proceed.

10 . The production method of the vinyl alcohol polymer according to claim 7 , wherein in the reacting, a second vinyl ester polymer comprising a thioester group on a side chain thereof is saponified in the presence of the second compound by using an alkali catalyst so as to allow a saponification reaction in a vinyl ester unit and a reaction of the epoxy group with a mercapto group generated by the saponification reaction on the thioester group to concomitantly proceed.

11 . The production method of the vinyl alcohol polymer according to claim 8 , wherein in the reacting, a second vinyl ester polymer comprising a thioester group on a side chain thereof is saponified by using an alkali catalyst so as to allow a saponification reaction in a vinyl ester unit and a coupling reaction of mercapto groups generated by the saponification reaction on the thioester group to concomitantly proceed.

12 . An additive for a drilling mud comprising the vinyl alcohol polymer according to claim 1 .

13 . A drilling mud comprising as an additive, the vinyl alcohol polymer according to claim 1 .

14 . An additive for a drilling cement slurry comprising the vinyl alcohol polymer according to claim 1 .

15 . A drilling cement slurry comprising as an additive, the vinyl alcohol polymer according to claim 1 .

Assignees

• Kuraray Co

Inventors

• Kumaki Yosuke
• Saito yasutomo

Classifications

• C08F216/06 Primary

  Polyvinyl alcohol {; Vinyl alcohol} · CPC title

• C09K8/467

  containing additives for specific purposes · CPC title

• C09K8/44

  containing organic binders only · CPC title

• C04B2103/46

  Water-loss or fluid-loss reducers, hygroscopic or hydrophilic agents, water retention agents · CPC title

• C08F8/34

  Introducing sulfur atoms or sulfur-containing groups · CPC title