Alkoxysilane polysulphide

An alkoxysilane polysulfide of formula (I):

• (R3O)3-n(R1)nSi—CH2—(R2)CH—Z—Sx—Z—HC(R2)—CH2—Si(R1)n(OR3)3-n (I),
• in which:
• R1, which are identical or different, each represent a monovalent hydrocarbon group having from 1 to 18 carbon atoms;
• R2, which are identical or different, each represent a monovalent hydrocarbon group having from 1 to 4 carbon atoms;
• R3, which are identical or different, each represent a monovalent hydrocarbon group having from 1 to 12 carbon atoms;
• Z, which are identical or different, each represent a divalent hydrocarbon bonding group comprising from 1 to 16 carbon atoms;
• x is an integral or fractional number greater than or equal to 2;
• and
• n is an integer equal to 2.

An elastomeric composition based on at least a diene elastomer, an inorganic filler as reinforcing filler and an alkoxysilane polysulfide as coupling agent, of formula (I):

• (R3O)3-n(R1)nSi—CH2—(R2)CH—Z—Sx—Z—HC(R2)—CH2—Si(R1)n(OR3)3-n (I),
• in which:
• R1, which are identical or different, each represent a monovalent hydrocarbon group having from 1 to 18 carbon atoms;
• R2, which are identical or different, each represent a monovalent hydrocarbon group having from 1 to 4 carbon atoms;
• R3, which are identical or different, each represent a monovalent hydrocarbon group having from 1 to 12 carbon atoms;
• Z, which are identical or different, each represent a divalent hydrocarbon bonding group comprising from 1 to 16 carbon atoms;
• x is an integral or fractional number greater than or equal to 2;
• and
• n is an integer equal to 2.