Silane mixtures and process for preparing same

A silane mixture, comprising

• a silane of formula (I)
• (R1)y(R2)3-ySi—R3—(S—R4)n—Sx—R5 (I);
• and
• a silane of formula (II)
• (R1)y(R2)3-ySi—R3—S—R3—Si(R1)y(R2)3-y (II),
• wherein
• R1 is independently a C1-C10-alkoxy group, phenoxy group, C4-C10-cycloalkoxy group, or alkyl polyether group —O—(R6—O)r—R7 where R6 being a divalent C1-C30 hydrocarbon group, r being an integer in a range of from 1 to 30, and R7 being a monovalent alkyl, alkenyl, aryl, or aralkyl group,
• R2 is independently a C6-C20-aryl groups, C1-C10-alkyl groups, C2-C20-alkenyl groups, C7-C20-aralkyl group, or halogen,
• R3 is independently a divalent C1-C30 hydrocarbon group,
• R4 is independently a divalent C1-C30 hydrocarbon group,
• x is an integer in a range of from 1 to 10,
• wherein, when x is 1, R5 is a —C(═O)—R8 group with R8 being H, a C1-C20 alkyl group, C6-C20-aryl group, C2-C20-alkenyl group, or a C7-C20-aralkyl group and n is 0, 1, 2, or 3,
• wherein, when x is in a range of from 2 to 10, R5 is —(R4—S)n—R3—Si(R1)y(R2)3-y and n is 1, 2 or 3, and
• y is independently 1, 2, or 3, or
• wherein the silane of the formula (I) is (EtO)3Si—(CH2)3—S—(CH2)6—S2—(CH2)6—S—(CH2)3—Si(OEt)3, (EtO)3Si—(CH2)—S—(CH2)6—S—C(═O)—CH3, (EtO)3Si—(CH2)3—S—(CH2)6—S—C(═O)—C7H15, or (EtO)3Si—(CH2)3—S—(CH2)6—S-—C(═O)—C17H35, and the silane of the formula (II) is (EtO)3Si—(CH2)3—S—(CH2)3—Si(OEt)3,
• and
• wherein a molar ratio of the silane of the formula (I) to the silane of the formula (II) is in a range of from 20:80 to 90:10.