Sulfur-containing organosilicon compound, making method, rubber compounding ingredient, and rubber composition

1. A sulfur-containing organosilicon compound obtained from transesterification reaction of a sulfide-containing organosilicon compound with an amide compound,

said sulfide-containing organosilicon compound having the formula (1):

(R 1 O) (3-p) (R 2 ) p Si—R 3 —S n —R 3 —Si(OR 1 ) (3-p) (R 2 ) p   (1)

wherein R 1 and R 2 are each independently a monovalent hydrocarbon group of 1 to 4 carbon atoms, R 3 is a divalent hydrocarbon group of 1 to 10 carbon atoms, n is a number having an average value in the range of 2≦n≦6, and p is an integer of 0 to 2,

said amide compound having the formula (2):

wherein R 4 is a monovalent hydrocarbon group of 1 to 20 carbon atoms, R 5 is a group of the formula (3), and R 6 is hydrogen, an alkyl group of 1 to 12 carbon atoms, an aryl group of 6 to 12 carbon atoms or a group of the formula (3):

*—(CH 2 ) s —R 7 —OH  (3)

wherein R 7 is an alkylene group of 1 to 12 carbon atoms or *—O—(Y—O) m —Y—*, Y is an alkylene group of 1 to 10 carbon atoms, m is a number of 1 to 40, and s is a number of 0 to 12, and * designates a bonding site.

2. The sulfur-containing organosilicon compound of claim 1 wherein the amide compound having the formula (2) is selected from compounds having the formulae (4) to (7):

wherein R 4 , R 6 and s are as defined above, and q is a number of 1 to 40.

3. The sulfur-containing organosilicon compound of claim 1 wherein in the reaction, 1 to 200 parts by weight of the amide compound having formula (2) is used per 100 parts by weight of the sulfide-containing organosilicon compound having formula (1).

4. A method for preparing a sulfur-containing organosilicon compound of claim 1 comprising transesterification reaction of a sulfide-containing organosilicon compound with an amide compound in the presence of a catalyst,

said sulfide-containing organosilicon compound having the formula (1):

(R 1 O) (3-p) (R 2 ) p Si—R 3 —S n —R 3 —Si(OR 1 ) (3-p) (R 2 ) p   (1)

wherein R 1 and R 2 are each independently a monovalent hydrocarbon group of 1 to 4 carbon atoms, R 3 is a divalent hydrocarbon group of 1 to 10 carbon atoms, n is a number having an average value in the range of 2≦n≦6, and p is an integer of 0 to 2,

said amide compound having the formula (2):

wherein R 4 is a monovalent hydrocarbon group of 1 to 20 carbon atoms, R 5 is a group of the formula (3), and R 6 is hydrogen, an alkyl group of 1 to 12 carbon atoms, an aryl group of 6 to 12 carbon atoms or a group of the formula (3):

*—(CH 2 ) s —R 7 —OH  (3)

wherein R 7 is an alkylene group of 1 to 12 carbon atoms or *—O—(Y—O) m —Y—*, Y is an alkylene group of 1 to 10 carbon atoms, m is a number of 1 to 40, and s is a number of 0 to 12, and * designates a bonding site.

5. The method of claim 4 wherein the amide compound having the formula (2) is selected from compounds having the formulae (4) to (7):

wherein R 4 , R 6 and s are as defined above, and q is a number of 1 to 40.

6. The method of claim 4 wherein 1 to 200 parts by weight of the amide compound having formula (2) is used per 100 parts by weight of the sulfide-containing organosilicon compound having formula (1).

7. The method of claim 4 wherein the catalyst is an acid, alkaline metal alcoholate, or organometallic catalyst.

8. A rubber compounding ingredient comprising the sulfur-containing organosilicon compound of claim 1 .

9. The rubber compounding ingredient of claim 8 , further comprising at least one powder, wherein the sulfur-containing organosilicon compound (A) and the at least one powder (B) are present in a weight ratio A/B of 70/30 to 5/95.

10. A rubber composition comprising the rubber compounding ingredient of claim 8 .

11. A tire comprising the rubber composition of claim 10 .