Process for preparing blends of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene

Patent metadata

Field	Value
Publication number	US-10035908-B1
Application number	US-201615149816-A
Country	US
Kind code	B1
Filing date	May 9, 2016
Priority date	Dec 3, 2013
Publication date	Jul 31, 2018
Grant date	Jul 31, 2018

Abstract

A process for preparing a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene, the process comprising the steps of (i) polymerizing 1,3-butadiene in the presence of a lanthanide-based catalyst to form a polymerization mixture including trans-1,4-polybutadiene, where the lanthanide-based catalyst includes (a) a lanthanide-containing compound, and (b) an organomagnesium compound; and (ii) polymerizing 1,3-butadiene in the presence of an iron-based catalyst within the polymerization mixture including trans-1,4-polybutadiene to form syndiotactic 1,2-polybutadiene within the polymerization mixture including trans-1,4-polybutadiene and thereby produce a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene; where the iron-based catalyst includes (a) an iron-containing compound, (b) an organomagnesium compound, and (c) a silyl phosphonate.

First claim

What is claimed is:

1. A process for preparing a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene, the process comprising the steps of:
(i) polymerizing 1,3-butadiene in the presence of a lanthanide-based catalyst to form a polymerization mixture including trans-1,4-polybutadiene, where the lanthanide-based catalyst includes (a) a lanthanide-containing compound, and (b) an organomagnesium compound; and
(ii) polymerizing 1,3-butadiene in the presence of an iron-based catalyst within the polymerization mixture including trans-1,4-polybutadiene to form syndiotactic 1,2-polybutadiene within the polymerization mixture including trans-1,4-polybutadiene and thereby produce a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene; where the iron-based catalyst includes (a) an iron-containing compound, (b) an organomagnesium compound, and (c) a silyl phosphonate.

2. The process of claim 1 , where the organomagnesium compound is defined by the formula MgR 2 , where each R independently is a monovalent organic group that is attached to the magnesium atom via a carbon atom.

3. The process of claim 1 , where the organomagnesium compound is defined by the formula RMgX, where R is a monovalent organic group that is attached to the magnesium atom via a carbon atom, and X is a hydrogen atom, a carboxylate group, an alkoxide group, or an aryloxide group.

4. The process of claim 1 , where the silyl phosphonate compound is defined by the formula

where each R 1 , which may be the same or different, is a hydrogen atom or a mono-valent organic group.

5. The process of claim 1 , where the silyl phosphonate compound is defined by the formula

where each R 2 , which may be the same or different, is a hydrogen atom or a mono-valent organic group, and R 3 is a bond or a divalent organic group.

6. The process of claim 1 , where the organomagnesium compound is defined by the formula MgR 2 , where each R independently is a monovalent organic group that is attached to the magnesium atom via a carbon atom.

7. The process of claim 1 , where the organomagnesium compound is defined by the formula RMgX, where R is a monovalent organic group that is attached to the magnesium atom via a carbon atom, and X is a hydrogen atom, a carboxylate group, an alkoxide group, or an aryloxide group.

8. The process of claim 1 , where said step of polymerizing 1,3-butadiene in the presence of a lanthanide-based catalyst takes place within a first vessel, and where said step of polymerizing 1,3-butadiene in the presence of an iron-based catalyst takes place within a second vessel.

9. The process of claim 8 , where the polymerization mixture including a trans-1,4-polybutadiene is transferred from the first vessel to the second vessel without quenching the polymerization mixture or the trans-1,4-polybutadiene.

10. The process of claim 1 , where said step of polymerizing 1,3-butadiene in the presence of a lanthanide-based catalyst and said step of polymerizing 1,3-butadiene in the presence of an iron-based catalyst takes place within a single vessel.

11. The process of claim 1 , where said step of polymerizing 1,3-butadiene in the presence of a lanthanide-based catalyst takes place within a first zone of a reactor, and where said step of polymerizing 1,3-butadiene in the presence of an iron-based catalyst takes place within a second zone of the reactor.

12. A process for preparing a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene, the process comprising:
(i) introducing a lanthanide-based catalyst and 1,3-butadiene monomer to form a polymerization mixture, where the lanthanide-based catalyst includes (a) a lanthanide-containing compound, and (b) an organomagnesium compound;
(ii) allowing the 1,3-butadiene monomer to polymerize to form trans-1,4-polybutadiene and thereby form a polymerization mixture including trans-1,4-polybutadiene;
(iii) introducing an iron-based catalyst to the polymerization mixture including the trans-1,4-polybutadiene, where the iron-based catalyst includes (a) an iron-containing compound, (b) an organomagnesium compound, and (c) a silyl phosphonate, where the silyl phosphonate is selected from silyl phosphonate compounds defined by one of the formulae

 where each R 1 , which may be the same or different, is a hydrogen atom or a mono-valent organic group, or

 where each R 2 , which may be the same or different, is a hydrogen atom or a mono-valent organic group, and R 3 is a bond or a divalent organic group; and
(iv) allowing the 1,3-butadiene monomer to polymerize to form syndiotactic 1,2-polybutadiene within the polymerization mixture including the trans-1,4-polybutadiene.

13. The process of claim 12 , where said step of introducing an iron-based catalyst takes place after the conversion of 1,3-butadiene monomer to trans-1,4-polybutadiene reaches at least 5% and before the conversion of 1,3-butadiene to trans-1,4-polybutadiene reaches at most 90%.

14. A process for preparing a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene, the process comprising:
(i) providing an active polymerization mixture including a propagating trans-1,4-polybutadiene polymer, where the lanthanide-based catalyst includes (a) a lanthanide-containing compound, and (b) an organomagnesium compound; and
(ii) adding an iron-based catalyst to the active polymerization mixture including the propagating trans-1,4-polybutadiene polymer, where the iron-based catalyst includes (a) an iron-containing compound, (b) an organomagnesium compound, and (c) a silyl phosphonate, where the silyl phosphonate is selected from silyl phosphonate compounds defined by one of the formulae

 where each R 1 , which may be the same or different, is a hydrogen atom or a mono-valent organic group, or

 where each R 2 , which may be the same or different, is a hydrogen atom or a mono-valent organic group, and R 3 is a bond or a divalent organic group.

15. The process of claim 14 , further comprising the step of adding 1,3-butadiene monomer to the active polymerization mixture.

16. A vulcanizable composition comprising:
the blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene prepared by a process for preparing a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene, the process comprising the steps of:
(i) polymerizing 1,3-butadiene in the presence of a lanthanide-based catalyst to form a polymerization mixture including trans-1,4-polybutadiene, and
(ii) polymerizing 1,3-butadiene in the presence of an iron-based catalyst within the polymerization mixture including trans-1,4-polybutadiene to form syndiotactic 1,2-polybutadiene within the polymerization mixture including trans-1,4-polybutadiene and thereby produce a blend of trans-1,4-polybutadiene and syndiotactic 1,2-polybutadiene, a filler, and a curative.

17. A tire component prepared by employing the blend of trans-1,4-polybutadiene and syndiota

Assignees

• Bridgestone Corp

Inventors

• Luo Steven
• Agarwal Sheel
• Rensel John D

Classifications

• C08L47/00 Primary

  Compositions of homopolymers or copolymers of compounds having one or more unsaturated aliphatic radicals, at least one having two or more carbon-to-carbon double bonds; Compositions of derivatives of such polymers (C08L45/00 takes precedence; of conjugated diene rubbers C08L9/00 - C08L21/00) · 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

• C08L2314/08

  prepared by late transition metal, i.e. Ni, Pd, Pt, Co, Rh, Ir, Fe, Ru or Os, single site catalyst · CPC title

• C08L2207/10

  Peculiar tacticity · CPC title

• B60C1/0016 Primary

  Compositions of the tread · CPC title