Functionalized polymer, rubber composition and pneumatic tire
The present invention is directed to a functionalized elastomer comprising the reaction product of a living anionic elastomeric polymer and a polymerization terminator of formula I where n is an integer from 1 to 3; X is a tetravalent organic group selected from a hydrocarbyl group of formula C m H 2m-2 where m is an integer from 1 to 10, a group of formula II where R 3 is C1 to C10 alkane diyl, and the group of phenyl diyl; R 1 and R 2 are independently selected from C1 to C10 alkyl, and a group of formula III where R 4 , R 5 are independently C1 to C10 alkyl, and R 6 is C1 to C10 alkanediyl; or R 1 and R 2 taken together with their common Si atom form a five-membered heterocyclic ring selected from formulas IV and V where R7 is from C1 to C10 alkyl.
1. A functionalized elastomer comprising the reaction product of a living anionic elastomeric polymer and a polymerization terminator of formula I
where n is an integer from 1 to 3;
X is a tetravalent organic group selected from a hydrocarbyl group of formula C m H 2m-2 where m is an integer from 1 to 10, a group of formula II
where R 3 is C1 to C10 alkane diyl, and the group of phenyl diyl;
R 1 and R 2 are independently selected from C1 to C10 alkyl, and a group of formula III
where R 4 , R 5 are independently C1 to C10 alkyl, and R 6 is C1 to C10 alkanediyl;
or R 1 and R 2 taken together with their common Si atom form a five-membered heterocyclic ring selected from formulas IV and V
where R7 is from C1 to C10 alkyl.
2. The functionalized elastomer of claim 1 , wherein the living anionic elastomer is derived from at least one diene monomer and optionally at least one vinyl aromatic monomer.
3. The functionalized elastomer of claim 1 , wherein the living anionic elastomer is derived from at least one of isoprene and butadiene, and optionally from styrene.
4. The functionalized elastomer of claim 1 , wherein the living anionic elastomer is derived from butadiene and styrene.
5. The functionalized elastomer of claim 1 , wherein the polymerization terminator is selected from the following structures 1-4:
where R′ is C1 to C10 alkyl
where Me is methyl
6. A rubber composition comprising the functionalized elastomer of claim 1 .
7. The rubber composition of claim 6 , further comprising silica.
8. A pneumatic tire comprising the rubber composition of claim 7 .