Functionalized polymer, rubber composition and pneumatic tire
There is disclosed a functionalized elastomer 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 alkanediyl, C1 to C8 arylene, C1 to C8 alkylarylene, C1 to C8 arylalkanediyl, or a covalent bond; R 5 is C2 alkanediyl; Si is silicon; X is sulfur or oxygen; and P is a diene based elastomer, and n is 1 or 2.
1. A functionalized elastomer of formula I
where; Si is silicon; S is sulfur; P is a diene based elastomer, and n is 1 or 2.
2. The functionalized elastomer of claim 1 , wherein n is 1.
3. The functionalized elastomer of claim 1 , wherein n is 2.
4. The functionalized elastomer of claim 1 , wherein P is derived from at least one diene monomer and optionally at least one vinyl aromatic monomer.
5. The functionalized elastomer of claim 1 , wherein P is derived from at least one of isoprene and butadiene, and optionally from styrene.
6. The functionalized elastomer of claim 1 , wherein P is derived from butadiene and styrene.
7. A rubber composition comprising the functionalized elastomer of claim 1 .
8. The rubber composition of claim 7 , further comprising silica.
9. A pneumatic tire comprising the rubber composition of claim 8 .
10. A method of making a functionalized elastomer, comprising the steps of
A) reacting a metal terminated diene based elastomer living polymer with ethylene sulfide to form a first terminated polymer; and
B) reacting the first terminated polymer with chlorotriethoxysilane.
11. The method of claim 10 , wherein the diene based elastomer is derived from at least one diene monomer and optionally at least one vinyl aromatic monomer.
12. The method of claim 10 , wherein the diene based elastomer is derived from at least one of isoprene and butadiene, and optionally from styrene.
13. The method of claim 10 , wherein the diene based elastomer is derived from butadiene and styrene.