Functionalized elastomer containing a boron group
The present invention is directed to a copolymer of 1,3-butadiene or isoprene and a monomer of formula I or V wherein R 1 is a covalent bond, phenylene, a linear or branched alkane diyl group containing 1 to 10 carbon atoms, or a combination of one or more phenylene groups and one or more linear or branched alkane diyl groups containing 1 to 10 carbon atoms; R 2 and R 3 are independently linear or branched alkyl groups containing 1 to 10 carbon atoms; or R 5 is a linear or branched alkane diyl group containing 1 to 20 carbon atoms, or a bridging aromatic group. The invention is further directed to a rubber composition including the copolymer, and a pneumatic tire containing the rubber composition. The invention is further directed to a method of making such a copolymer.
1. A copolymer of a first monomer selected from the group consisting of 1,3-butadiene and isoprene, and a second monomer
2. The copolymer of claim 1 , comprising from 0.1 to 40 percent by weight of units derived from the second monomer, based on the weight of the copolymer.
3. The copolymer of claim 1 , comprising from 0.5 to 20 percent by weight of units derived from the second monomer based on the weight of the copolymer.
4. The copolymer of claim 1 , comprising from 1 to 5 percent by weight of units derived from the second monomer based on the weight of the copolymer.
5. A rubber composition comprising the copolymer of claim 1 .
6. A pneumatic tire comprising the rubber composition of claim 5 .
7. A method of making a copolymer, comprising the step of polymerizing a monomer selected from the group consisting of 1,3-butadiene and isoprene and the monomer
8. The method of claim 7 wherein the polymerization is done in the presence of a catalyst of formula II
where BAr F 4 − is tetrakis(3,5-bis(trifluoromethyl)phenyl) borate.