Functionalized polymer, rubber composition and pneumatic tire
There is disclosed a functionalized elastomer comprising the reaction product of a living anionic elastomeric polymer; and a polymerization terminator of formula I where R 1 , R 2 and R 3 are independently C1 to C8 alkyl or C1 to C8 alkoxy, with the proviso that at least two of R 1 , R 2 and R 3 are C1 to C8 alkoxy; R 4 is C1 to C8 alkyl; Si is silicon; S is sulfur; and Z is R 5 or of formula II where R 5 is alkyl, aryl, alkylaryl or arylalkyl. There is further disclosed a rubber composition comprising the functionalized elastomer, and a pneumatic tire comprising the rubber composition.
1. A functionalized elastomer comprising the reaction product of
a living anionic elastomeric polymer; and
a polymerization terminator of formula I
where R 1 , R 2 and R 3 are independently C1 to C8 alkyl or C1 to C8 alkoxy, with the proviso that at least two of R 1 , R 2 and R 3 are C1 to C8 alkoxy; R 4 is C1 to C8 alkyl; Si is silicon; S is sulfur; and Z is R 5 or of formula II
where R 5 is alkyl, aryl, alkylaryl or arylalkyl.
2. The functionalized elastomer of claim 1 , wherein R 1 , R 2 and R 3 are each C1 to C8 alkoxy.
3. The functionalized elastomer of claim 1 , wherein Z is of formula II.
4. The functionalized elastomer of claim 1 , wherein Z is alkyl, aryl, alkylaryl, or arylalkyl.
5. 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.
6. 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.
7. The functionalized elastomer of claim 1 , wherein the living anionic elastomer is derived from butadiene and styrene.
8. The functionalized elastomer of claim 1 , wherein the polymerization terminator of formula I has the structure
where Et is ethyl.
9. A rubber composition comprising the functionalized elastomer of claim 1 .
10. The rubber composition of claim 9 , further comprising silica.
11. A pneumatic tire comprising the rubber composition of claim 9 .