Polymers functionalized with nitroso compounds

1. A method for preparing a functionalized cis-1,4-polydiene polymer, the method comprising the steps of:

(i) polymerizing conjugated diene monomer with a lanthanide-based catalyst to form a reactive cis-1,4-polydiene polymer; and

(ii) reacting the reactive polymer with a nitroso compound to thereby form a functionalized cis-1,4-polydiene defined by the formula:

where π is a cis-1,4-polydiene chain having a cis-1,4-linkage content of greater than 60%, where β is a mono-valent organic group, and where R′ is a hydrogen atom or a mono-valent organic group.

2. The method of claim 1 , where the nitroso compound is defined by the formula β—N═O, where β is a mono-valent organic group and —N═O is a nitroso group.

3. The method of claim 2 , where the mono-valent organic group β is bonded to the nitroso group through a carbon atom, a nitrogen atom, an oxygen atom, or a sulfur atom that resides within the β group.

4. The method of claim 2 , where the mono-valent organic group β is selected from the groups consisting of hydrocarbyl groups, substituted hydrocarbyl groups, protected amino groups, hydrocarbyloxy groups, substituted hydrocarbyloxy groups, hydrocarbylthio groups, and substituted hydrocarbylthio groups.

5. The method of claim 2 , where the nitroso compound is selected from the group consisting of C-nitroso compounds, N-nitroso compounds, O-nitroso compounds, and S-nitroso compounds.

6. The method of claim 5 , where the nitroso compound is a C-nitroso compound.

7. The method of claim 5 , where the nitroso compound is an N-nitroso compound.

8. The method of claim 5 , where the nitroso compound is an O-nitroso compound.

9. The method of claim 5 , where the nitroso compound is an S-nitroso compound.

10. The method of claim 6 , where the nitroso compound is a C-nitroso compound selected from the group consisting of nitrosomethane, nitrosoethane, 1-nitroso-n-propane, 2-nitroso-n-propane, 1-nitroso-n-butane, 2-methyl-2-nitrosopropane, 1-nitroso-n-pentane, 1-nitroso-n-hexane, 1-nitroso-n-heptane, 1-nitroso-n-octane, 1-nitroso-n-nonane, 1-nitroso-n-decane, 1-nitroso-n-dodecane, nitrosocyclopentane, nitrosocyclohexane, nitrosocyclooctane, nitrosobenzene, 2-nitrosotoluene, 3-nitrosotoluene, 4-nitrosotoluene, N,N-dimethyl-4-nitrosoaniline, N,N-diethyl-4-nitrosoaniline, 2-nitrosopyridine, 3-nitrosopyridine, 4-nitrosopyridine, nitrosopyrazine, 2-nitrosopyrimidine, 4-nitrosopyrimidine, 5-nitrosopyrimidine, 3-nitrosopyridazine, 4-nitrosopyridazine, 2-nitrosoquinoline, 3-nitrosoquinoline, 4-nitrosoquinoline, 1-nitrosophthalazine, 2-nitrosoquinazoline, 4-nitrosoquinazoline, 2-nitrosoquinoxaline, 2-nitroso-1,10-phenanthroline, 3-nitroso-1,10-phenanthroline, 4-nitroso-1,10-phenanthroline, 5-nitroso-1,10-phenanthroline, 1-nitrosophenazine, 2-nitrosophenazine, N-methyl-2-nitrosopyrrolidine, N-2-nitrosopyrrole, N-methyl-3-nitrosopyrrole, N-methyl-2-nitrosoimidazole, N-methyl-4-nitrosoimidazole, N-methyl-5-nitrosoimidazole, N-methyl-3-nitrosopyrazole, N-methyl-4-nitrosopyrazole, N-methyl-5-nitrosopyrazole, N-methyl-2-nitrosopiperidine, N-methyl-2-nitrosohomopiperidine, N-methyl-2-nitrosomorpholine, N-(trimethylsilyl)-2-nitrosopyrrolidine, N-(trimethylsilyl)-2-nitrosopyrrole, N-(trimethylsilyl)-3-nitrosopyrrole, N-(trimethylsilyl)-2-nitrosoimidazole, N-(trimethylsilyl)-4-nitrosoimidazole, N-(trimethylsilyl)-5-nitrosoimidazole, N-(trimethylsilyl)-3-nitrosopyrazole, N-(trimethylsilyl)-4-nitrosopyrazole, N-(trimethylsilyl)-5-nitrosopyrazole, N-(trimethylsilyl)-2-nitrosopiperidine, N-(trimethylsilyl)-2-nitrosohomopiperidine, and N-(trimethylsilyl)-2-nitrosomorpholine.

11. The method of claim 7 , where the nitroso compound is an N-nitroso compound selected from the group consisting of N-nitrosopyrrolidine, N-nitrosopyrrole, N-nitrosoimidazole, N-nitrosopyrazole, N-nitrosopiperidine, N-nitrosohomopiperidine, N-nitrosomorpholine, N-nitrosonornicotine, N-nitrosodimethylamine, N-nitrosodiethylamine, N-nitrosodi-n-propylamine, N-nitrosodiisopropylamine N-nitrosodi-n-butylamine, N-nitrosodiisobutylamine, N-nitrosodi-t-butylamine, N-nitrosodineopentylamine, N-nitrosodiphenylamine, N-nitrosodibenzylamine, N-nitrosodi-2-tolylamine, N-nitrosodi-3-tolylamine, N-nitrosodi-4-tolylamine, N-nitrosodi-2-pyridylamine, N-benzyl-N-nitroso-p-toluenesulfonamide, N-nitrosobis(trimethylsilyl)amine, N-nitrosobis(triethylsilyl)amine, N-nitrosobis(triisopropylsilyl)amine, N-nitrosobis(triphenylsilyl)amine, and N-nitroso (trimethylsilyl)(methyl)amine.

12. The method of claim 8 , where the nitroso compound is an O-nitroso compound selected from the group consisting of methyl nitrite, ethyl nitrite, n-propyl nitrite, isopropyl nitrite, n-butyl nitrite, isobutyl nitrite, t-butyl nitrite, neopentyl nitrite, benzyl nitrite, phenyl nitrite, trimethylsilyl nitrite, triethylsilyl nitrite, triisopropylsilyl nitrite, and triphenylsilyl nitrite.

13. The method of claim 9 , where the nitroso compound is an S-nitroso compound selected from the group consisting of methyl thionitrite, ethyl thionitrite, n-propyl thionitrite, isopropyl thionitrite, n-butyl thionitrite, isobutyl thionitrite, t-butyl thionitrite, neopentyl thionitrite, benzyl thionitrite, phenyl thionitrite trimethylsilyl thionitrite, triethylsilyl thionitrite, triisopropylsilyl thionitrite, and triphenylsilyl thionitrite.

14. The method of claim 1 , where the lanthanide-based catalyst includes (a) a lanthanide compound, (b) an alkylating agent, and (c) a halogen-containing compound.

15. The method of claim 14 , where the alkylating agent includes an aluminoxane and an organoaluminum compound represented by the formula AlR n X 3-n , where each R, which may be the same or different, is a mono-valent organic group that is attached to the aluminum atom via a carbon atom, where each X, which may be the same or different, is a hydrogen atom, a halogen atom, a carboxylate group, an alkoxide group, or an aryloxide group, and where n is an integer of 1 to 3.

16. The method of claim 1 , where said step of polymerizing monomer takes place within a polymerization mixture including less than 20% by weight of organic solvent.

17. The method of claim 1 , wherein the functionalized cis-1,4-polydiene has a cis-1,4-polydiene chain with a cis-1,4-linkage content that is greater than 75%.

18. The method of claim 1 , wherein the functionalized cis-1,4-polydiene has a cis-1,4-polydiene chain with a cis-1,4-linkage content that is greater than 90%.