Process for producing conjugated diene polymer

Patent metadata

Field	Value
Publication number	US-10246525-B2
Application number	US-201515506495-A
Country	US
Kind code	B2
Filing date	Sep 7, 2015
Priority date	Sep 9, 2014
Publication date	Apr 2, 2019
Grant date	Apr 2, 2019

Abstract

The present invention provides a process for producing a conjugated diene polymer, the process including a production step of producing a conjugated diene polymer solution containing a conjugated diene polymer and a solvent, and a devolatilization step of heating the conjugated diene polymer solution while conveying the conjugated diene polymer solution with an apparatus having rotary twin screws, thereby devolatilizing the solvent, in which a motor current value of the screw in the devolatilization step and a motor current value of the screw under no load satisfy a predetermined relational expression.

First claim

The invention claimed is:

1. A process for producing a conjugated diene polymer, the process comprising:
a production step of producing a conjugated diene polymer solution comprising a conjugated diene polymer and a solvent; and
a devolatilization step of heating the conjugated diene polymer solution while conveying the conjugated diene polymer solution with an apparatus comprising rotary twin screws, thereby devolatilizing the solvent,
wherein a motor current value of the screw in the devolatilization step and a motor current value of the screw under no load satisfy following relational expression (1):
1.05≤(( I 1 )/( I 0 ))≤2.00  (1)

wherein I 1 represents the motor current value [A] of the screw in the devolatilization step and I 0 represents the motor current value [A] of the screw under no load,
wherein:
a ratio of a screw length to a screw diameter in the apparatus is 4.0 or more and 12 or less; and,
in the devolatilization step, an inner volume of the apparatus and an amount of the solvent volatilizing per unit time satisfy following relational expression (2):
1.0≤(( V A )/( V 0 ))≤50  (2)

wherein (V 0 ) represents the inner volume [L] of the apparatus and (V A ) represents the amount [L] of the solvent volatilizing per unit time [h].

2. The process for producing the conjugated diene polymer according to claim 1 , wherein the conjugated diene polymer has a weight average molecular weight of 100,000 or higher and 2,000,000 or lower.

3. The process for producing the conjugated diene polymer according to claim 1 , wherein the conjugated diene polymer solution comprises 5.0% by mass or more and 95% by mass or less of the conjugated diene polymer based on the total amount of the conjugated diene polymer solution.

4. The process for producing the conjugated diene polymer according to claim 1 , wherein the conjugated diene polymer solution comprises 5.0 parts by mass or more and 100 parts by mass or less of oil based on 100 parts by mass of the conjugated diene polymer.

5. The process for producing the conjugated diene polymer according to claim 1 , wherein two or more of apparatuses each comprising twin screws are used in the devolatilization step.

6. The process for producing the conjugated diene polymer according to claim 1 , wherein the conjugated diene polymer comprises 1.0% by mass or more and 99% by mass or less of a component having a molecular weight of 1000000 or higher based on the total amount of the conjugated diene polymer.

7. The process for producing the conjugated diene polymer according to claim 1 , wherein an average residence time in the devolatilization step is 10 seconds or longer and 300 seconds or shorter.

8. The process for producing the conjugated diene polymer according to claim 1 , wherein the devolatilization step is a step of devolatilizing the solvent until the content of the solvent reaches 5.0% by mass or less based on the total amount of the conjugated diene polymer obtained.

9. The process for producing the conjugated diene polymer according claim 1 , wherein the conjugated diene polymer is modified with a compound having at least one functional group selected from the group consisting of epoxy groups and alkoxysilyl groups.

10. The process for producing the conjugated diene polymer according to claim 9 , wherein the compound is at least one compound selected from the group consisting of compounds represented by following general formula (3) and compounds represented by following general formula (4):

wherein R 1 and R 2 each independently represent an alkyl group having 1 to 10 carbon atoms or an alkyl group having 1 to 10 carbon atoms and having at least one functional group selected from the group consisting of ether groups and tertiary amine groups, R 3 and R 4 each independently represent a hydrogen atom, an alkyl group having 1 to 20 carbon atoms, or an alkyl group having 1 to 20 carbon atoms and having at least one functional group selected from the group consisting of ether groups and tertiary amine groups, R 5 represents an alkyl group having 1 to 20 carbon atoms or an alky group having 1 to 20 carbon atoms and having at least one functional group selected from the group consisting of ether groups, tertiary amine groups, epoxy groups, carbonyl groups and halogens, and n represents an integer of 1 to 6; and

wherein R 1 and R 2 each independently represent an alkyl group having 1 to 20 carbon atoms or an aryl group having 6 to 20 carbon atoms, R 3 and R 4 each independently represent an alkyl group having 1 to 20 carbon atoms, R 5 represents an alkyl group having 1 to 6 carbon atoms and forms a five or more-membered cyclic structure with an adjacent nitrogen atom and an adjacent silicon atom, R 6 represents an alkyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, not having an active hydrogen atom, and substituted with a heteroatom, or an organosubstituted silyl group, m represents an integer of 1 or 2, and n represents an integer of 2 or 3.

11. The process for producing the conjugated diene polymer according to claim 1 , wherein
the conjugated diene polymer has a weight average molecular weight of 100,000 or higher and 2,000,000 or lower,
the conjugated diene polymer solution comprises 5.0% by mass or more and 95% by mass or less of the conjugated diene polymer based on the total amount of the conjugated diene polymer solution,
the conjugated diene polymer solution comprises 5.0 parts by mass or more and 100 parts by mass or less of oil based on 100 parts by mass of the conjugated diene polymer,
two or more of apparatuses each comprising twin screws are used in the devolatilization step,
the conjugated diene polymer comprises 1.0% by mass or more and 99% by mass or less of a component having a molecular weight of 1000000 or higher based on the total amount of the conjugated diene polymer,
an average residence time in the devolatilization step is 10 seconds or longer and 300 seconds or shorter,
the devolatilization step is a step of devolatilizing the solvent until the content of the solvent reaches 5.0% by mass or less based on the total amount of the conjugated diene polymer obtained, and
the conjugated diene polymer is modified with a compound having at least one functional group selected from the group consisting of epoxy groups and alkoxysilyl groups.

12. The process for producing the conjugated diene polymer according to claim 2 , wherein the conjugated diene polymer solution comprises 5.0 parts by mass or more and 100 parts by mass or less of oil based on 100 parts by mass of the conjugated diene polymer.

13. The process for producing the conjugated diene polymer according to claim 2 , wherein two or more of apparatuses each comprising twin screws are used in the devolatilization step.

14. The process for producing the conjugated diene polymer according to claim 3 , wherein two or more of apparatuses each comprising twin screws are used in the devolatilization step.

Assignees

• Asahi Chemical Ind

Inventors

• Tokiwa Tetsuji

Classifications

• B29B13/06 Primary

  by drying (B29B13/08 takes precedence {; drying moulded articles or half products B29C37/0092}) · CPC title

• C08F8/08

  Epoxidation · CPC title

• B29B7/48

  with intermeshing devices, e.g. screws · CPC title

• B29K2009/00

  Use of rubber derived from conjugated dienes, as moulding material · CPC title

• C08F6/10

  Removal of volatile materials, e.g. solvents {(C08F6/001, C08F6/003, C08F6/005, C08F6/006, C08F6/008, C08F6/02, C08F6/04 take precedence)} · CPC title