Vinyl alcohol-based polymers and their uses

Abstract

To provide a vinyl alcohol-based polymer having equivalent properties compared with a vinyl alcohol-based polymer derived only from petroleum; to save oil resources when using the vinyl alcohol-based polymer (PVA); and to reduce discharge of carbon dioxide in manufacturing processes.SOLUTION: A vinyl alcohol-based polymer (X) is obtained by polymerizing a plant-based vinyl ester monomer (A) and a petroleum-based vinyl ester monomer (B), followed by saponification. A molar ratio of (A) and (B) is 5:95 to 100:0.SELECTED DRAWING: None

Claims

1. A powder of a vinyl alcohol-based polymer (X) obtained by polymerizing and saponifying a plant-derived vinyl ester monomer (A) and a petroleum-derived vinyl ester monomer (B), wherein the molar ratio of (A) / (B) is 5 / 95 to 90 / 10. The aforementioned plant-derived vinyl ester monomer (A) is vinyl acetate, and the aforementioned petroleum-derived vinyl ester monomer (B) is vinyl acetate. The degree of saponification is 60 mol% or more. The viscosity-average degree of polymerization is 150 to 5000. The vinyl alcohol polymer (X) further optionally contains units derived from other unsaturated monomers (C) copolymerizable with vinyl ester monomers. The other unsaturated monomer (C) is at least one selected from the group consisting of α-olefins, acrylic acid and its salts, acrylic acid esters, methacrylic acid and its salts, methacrylic acid esters, acrylamide, acrylamide derivatives, methacrylamide, methacrylamide derivatives, vinyl ethers, vinyl halides, vinylidene halides, allyl compounds, unsaturated dicarboxylic acids and their salts or their mono or dialkyl esters, vinylsilyl compounds, and isopropenyl acetate. The aforementioned plant-derived vinyl ester monomer (A) 14 C / C is 1.0 x 10 -14 The above 1.0 x 10 -12 The following is a powder of a vinyl alcohol-based polymer (X).

2. The vinyl alcohol-based polymer (X) powder according to Claim 1, wherein the vinyl alcohol-based polymer (X) contains an ethylene unit as a unit derived from another unsaturated monomer (C) copolymerizable with the vinyl ester monomer, and the content of ethylene units in the total structural units of the vinyl alcohol-based polymer (X) is 1 mol% or more and less than 20 mol%.

3. A slurry additive comprising a powder of the vinyl alcohol-based polymer (X) described in claim 1 or 2.

4. Drilling slurry containing the slurry additive described in claim 3.

5. Furthermore, the drilling slurry according to claim 4, further containing water and bentonite.

6. A cement slurry containing the slurry additive described in claim 3.

7. Furthermore, the cement slurry according to claim 6 further contains a liquid agent and a curable powder.

8. The product comprises a powder of the vinyl alcohol-based polymer (X) described in claim 1 or 2, A sealant for underground treatment, wherein the degree of saponification of the vinyl alcohol-based polymer (X) is 90 mol% or more.

9. The underground treatment sealant according to claim 8, wherein the vinyl alcohol-based polymer (X) comprises units derived from another unsaturated monomer (C) copolymerizable with a vinyl ester monomer.

10. Furthermore, the ground treatment sealant according to claim 8 or 9, further comprising a plasticizer.

11. A dispersion stabilizer for suspension polymerization of vinyl compounds, comprising a powder of the vinyl alcohol polymer (X) described in claim 1 or 2.

12. A method for producing a vinyl resin, comprising the step of performing suspension polymerization of a vinyl compound in the presence of the suspension polymerization dispersion stabilizer described in claim 11.

13. The process includes carrying out suspension polymerization of a vinyl compound in the presence of the aforementioned suspension polymerization dispersion stabilizer and a further dispersion stabilization aid. The method for producing a vinyl resin according to claim 12, wherein the dispersion stabilizing agent comprises a vinyl alcohol-based polymer (Y2) having a degree of saponification of less than 65 mol%.

14. A powder comprising a vinyl alcohol-based polymer (X) obtained by polymerizing and saponifying a plant-derived vinyl ester monomer (A), a petroleum-derived vinyl ester monomer (B), and optionally a chain transfer agent, The molar ratio of (A) / (B) is 5 / 95 to 90 / 10. The aforementioned plant-derived vinyl ester monomer (A) is vinyl acetate, and the petroleum-derived vinyl ester monomer (B) is vinyl acetate. The viscosity-average degree of polymerization is 100 to 700. The chain transfer agent is at least one selected from the group consisting of aldehydes, ketones, mercaptans, thiocarboxylic acids, and halogenated hydrocarbons. The 14 C / C ratio of the aforementioned plant-derived vinyl ester monomer (A) is 1.0 × 10⁻¹⁴ or more and 1.0 × 10⁻¹² or less. A dispersion stabilizing aid for suspension polymerization of vinyl compounds, wherein the degree of saponification of the vinyl alcohol polymer (X) is 20 mol% or more and less than 60 mol%.

15. The process includes carrying out suspension polymerization of a vinyl compound in the presence of the suspension polymerization dispersion stabilizer described in claim 14 and the suspension polymerization dispersion stabilizer, A method for producing a vinyl resin, wherein the aforementioned suspension polymerization dispersion stabilizer contains a vinyl alcohol-based polymer (Y3) with a degree of saponification of 65 mol% or more and a viscosity-average degree of polymerization of 600 or more.

16. A method for producing a vinyl resin according to claim 15, wherein the mass ratio of the dispersion stabilizer to the dispersion stabilizing aid (dispersion stabilizer / dispersion stabilizing aid) is 95 / 5 to 20 / 80.

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