Functionalized polymer, rubber composition, and pneumatic tire
The present invention is directed to a functionalized elastomer comprising the reaction product of a living elastomeric polymer and a polymerization terminator of formula I, wherein the functionalized elastomer comprises repeat units of a diene monomer and optionally a vinyl aromatic monomer, and the functionalized elastomer comprises at least 92 percent by weight of cis 1,4 microstructure content based on the weight of the polydiene content of the functionalized elastomer wherein R 1 is C1 to C4 linear alkyl, or C1 to C4 branched alkanediyl; X 1 , X 2 , X 3 are independently O, S, or a group of formula (II) or (III) where R 2 is C1 to C18 linear or branched alkyl; Z is R 3 , —OR 4 , or —R 5 —X 4 ; R 3 , R 4 are independently C1 to C18 linear or branched alkyl; R 5 is C1 to C18 alkanediyl or dialkyl ether diyl; X 4 is halogen or a group of structure IV, V, VI, VII or VIII wherein R 6 , R 7 , R 8 , R 9 , and R 10 are independently H or C1 to C8 alkyl; R 11 is C2 to C8 alkanediyl; R 12 and R 13 are independently H, aryl or C1 to C8 alkyl; Q is N or a group of structure IX wherein R 14 is C1 to C8 alk.
1. A functionalized elastomer comprising the reaction product of a living elastomeric polymer and a polymerization terminator of formula I, wherein the functionalized elastomer comprises repeat units of a diene monomer and optionally a vinyl aromatic monomer, and the functionalized elastomer comprises at least 92 percent by weight of cis 1,4 microstructure content based on the weight of the polydiene content of the functionalized elastomer
wherein R 1 is C1 to C4 linear alkyl, or C1 to C4 branched alkanediyl; X 1 , X 2 , X 3 are independently O, S, or a group of formula (II) or (III)
where R 2 is C1 to C18 linear or branched alkyl; Z is R 3 , —OR 4 , or —R 5 —X 4 ; R 3 , R 4 are independently C1 to C18 linear or branched alkyl; R 5 is C1 to C18 alkanediyl or dialkyl ether diyl; X 4 is halogen or a group of structure IV, V, VI, VII or VIII
wherein R 6 , R 7 , R 8 , R 9 , and R 10 are independently H or C1 to C8 alkyl; R 11 is C2 to C8 alkanediyl; R 12 and R 13 are independently H, aryl or C1 to C8 alkyl;
Q is N or a group of structure IX
wherein R 14 is C1 to C8 alkyl.
2. The functionalized elastomer of claim 1 , wherein the living elastomer is derived from at least one of isoprene and butadiene, and optionally from styrene.
3. The functionalized elastomer of claim 1 , wherein the living elastomer is derived from butadiene.
4. The functionalized elastomer of claim 1 , wherein the living elastomer is derived from butadiene and styrene.
5. The functionalized elastomer of claim 1 , wherein the polymerization terminator of formula I is selected from the group consisting of the following structures
ETTS: 1-ethoxy-2,8,9-trithia-5-aza-1-silabicyclo[3.3.3]undecane; or 1-ethoxy-thiosilitrane
ETAS: 1-ethoxy-2,8,9-trimethyl-2,5,8,9-tetraaza-1-silabicyclo[3.3.3]undecane; or 1-ethoxy-2,8,9-triazasilatrane
EPTI: 3,7,10-trimethyl-1-(3-(oxiran-2-ylmethoxy)propyl)-2,8,9-trioxa-5-aza-1-silabicyclo[3.3.3]undecane; or 1-(3-(oxiran-2-ylmethoxy)propyl)-3,7,10-trimethylsilatrane.
6. The functionalized elastomer of claim 1 , wherein the functionalized elastomer comprises at least 95 percent by weight of cis 1,4 microstructure content based on the weight of the polydiene content of the functionalized elastomer.
7. The functionalized elastomer of claim 1 , wherein the functionalized elastomer comprises at least 98 percent by weight of cis 1,4 microstructure content based on the weight of the polydiene content of the functionalized elastomer.
8. A rubber composition comprising the functionalized elastomer of claim 1 .
9. The rubber composition of claim 8 , further comprising silica.
10. A pneumatic tire comprising the rubber composition of claim 9 .
11. A method of making a functionalized elastomer, comprising the steps of polymerizing monomers comprising a diene monomer and optionally a vinyl aromatic monomer in the presence of a lanthanide-based coordination polymerization catalyst, and terminating the polymerization with a terminator of formula I
wherein R 1 is C1 to C4 linear alkyl, or C1 to C4 branched alkanediyl; X 1 , X 2 , X 3 are independently O, S, or a group of formula (II) or (III)
where R 2 is C1 to C18 linear or branched alkyl; Z is R 3 , —OR 4 , or —R 5 —X 4 ; R 3 , R 4 are independently C1 to C18 linear or branched alkyl; R 5 is C1 to C18 alkanediyl or dialkyl ether diyl; X 4 is halogen or a group of structure IV, V, VI, VII or VIII
wherein R 6 , R 7 , R 8 , R 9 , and R 10 are independently H or C1 to C8 alkyl; R 11 is C2 to C8 alkanediyl; R 12 and R 13 are independently H, aryl or C1 to C8 alkyl;
Q is N or a group of structure IX
wherein R 14 is C1 to C8 alkyl, wherein the functionalized elastomer comprises at least 92 percent by weight of cis 1,4 micro structure content based on the weight of the polydiene content of the functionalized elastomer.
12. The method of claim 11 , wherein the lanthanide-based coordination polymerization catalyst is a neodymium based catalyst.
13. The method of claim 11 , wherein the monomers comprise at least one of isoprene and butadiene, and optionally from styrene.
14. The method of claim 11 , wherein the monomer is butadiene.
15. The method of claim 11 , wherein the monomers are butadiene and styrene.
16. The method of claim 11 , wherein the terminator of formula I is selected from the group consisting of the following structures
ETTS: 1-ethoxy-2,8,9-trithia-5-aza-1-silabicyclo[3.3.3]undecane; or 1-ethoxy-thiosilitrane
ETAS: 1-ethoxy-2,8,9-trimethyl-2,5,8,9-tetraaza-1-silabicyclo[3.3.3]undecane; or 1-ethoxy-2,8,9-triazasilatrane
EPTI: 3,7,10-trimethyl-1-(3-(oxiran-2-ylmethoxy)propyl)-2,8,9-trioxa-5-aza-1-silabicyclo[3.3.3]undecane; or 1-(3-(oxiran-2-ylmethoxy)propyl)-3,7,10-trimethylsilatrane.
17. The method of claim 11 , wherein the functionalized elastomer comprises at least 95 percent by weight of cis 1,4 microstructure content based on the weight of the polydiene content of the functionalized elastomer.
18. The method of claim 11 , wherein the functionalized elastomer comprises at least 98 percent by weight of cis 1,4 microstructure content based on the weight of the polydiene content of the functionalized elastomer.