3-GLYCIDYLOXYPROPYLTRIALKOXYSILANES HAVING LONG-CHAIN ALKOXY GROUPS, PROCESSES FOR PRODUCTION AND USE
A novel compound, which is 3-glycidyloxypropyltri(-2-propylheptoxy)silane. A process for producing a 3-glycidyloxypropyltrialkoxysilane having long-chain alkoxy groups of formula (I) or of formula (II) where m=1 or 2, n=0 or 1, p=3, 4, 5, 6, 7, 8, 9 or 10, where the method includes heating 3-glycidyloxypropyltrimethoxysilane or 3-glycidyloxypropyltriethoxysilane, with a stoichiometric amount or an excess of a longer-chain alcohol from the group of the C5- to C16-alcohols, in the presence of titanium tetrabutoxide as catalyst, with stirring to a temperature of not more than 225° C., reacting, and then following the reaction by removing methanol/ethanol and excess reactant alcohol from the product mixture by distillation, optionally under reduced pressure. A method of using the 3-glycidyloxypropyltri(-2-propylheptoxy)silane for functionalization of rubber and using the rubber in treads for reducing rolling resistance in tires.
1 . A compound, wherein the compound is 3-glycidyloxypropyltri(-2-propylheptoxy)silane.
2 . A process for producing a 3-glycidyloxypropyltrialkoxysilane having long-chain alkoxy groups of formula (I):
or
of formula (II)
wherein m=1 or 2, n=0 or 1, p=3, 4, 5, 6, 7, 8, 9 or 10,
the process comprising:
heating 3-glycidyloxypropyltrimethoxysilane or 3-glycidyloxypropyltriethoxysilane, with a stoichiometric amount or an excess of a longer-chain alcohol from the group of the C5- to C16-alcohols, in the presence of titanium tetrabutoxide as catalyst, with stirring to a temperature of not more than 225° C.,
reacting to obtain a product mixture, and
after the reacting, removing methanol/ethanol and excess reactant alcohol from the product mixture by distillation, to obtain a product.
3 . The process according to claim 2 ,
wherein the long-chain alcohol employed is 2-ethylhexan-1-ol, isononan-1-ol or 2-propylheptan-1-ol.
4 . The process according to claim 2 ,
wherein glycidyloxypropyltrimethoxysilane or glycidyloxypropyltriethoxysilane and a long-chain alcohol, are employed in a molar ratio of 1:3 to 6.
5 . The process according to claim 2 ,
wherein 0.01% to 0.5% by weight of titanium tetrabutoxide based on the employed amount of 3-glycidyloxypropyltrimethoxysilane is employed.
6 . The process according to claim 2 ,
wherein the reaction is performed at a temperature of 100 to 220° C.
7 . The process according to claim 2 ,
wherein the reaction is performed over a period of 6 to 24 hours.
8 . The process according to claim 2 ,
wherein the transesterification is performed with a yield of ≥90%.
9 . The process according to claim 2 ,
wherein a product is obtained as a composition having a content of 3-glycidyloxypropyltri(-2-ethylhexoxy)silane/3-glycidyloxypropyltri(-2-propylheptoxy)silane of ≥90% by weight, wherein the components in the composition sum to 100% by weight.
10 . A composition, comprising a content of 3-glycidyloxypropyltri(-2-ethylhexoxy)silane or 3-glycidyloxypropyltri(-2-propylheptoxy)silane of ≥90% by weight obtained by the process according to claim 2 , wherein the components in the composition sum to 100% by weight.
11 . The composition according to claim 10 , comprising a content of 3-glycidyloxypropyltri(-2-ethylhexoxy)silane or 3-glycidyloxypropyltri(-2-propylheptoxy)silane of ≥95%.
12 . The composition according to claim 10 , comprising a content of alcohols of methanol or ethanol of ≤1% by weight, based on the composition.
13 . The composition according to claim 10 , having a content of mixed esters ≤10% by weight, wherein the mixed esters are selected from the group consisting of 3-glycidyloxypropyldi(-2-ethylhexoxy)monomethoxysilane, 3-glycidyloxypropyldi(-2-ethylhexoxy)monoethoxysilane, 3-glycidyloxypropylmono(-2-ethylhexoxy)dimethoxysilane and 3-glycidyloxypropylmono(-2-ethylhexoxy)diethoxysilane.
14 . A method of functionalizing rubber, comprising anionically polymerizing the rubber in the presence of the composition according to claim 10 , wherein the 3-glycidyloxypropyltri(-2-ethylhexoxy)silane or 3-glycidyloxypropyltri(-2-propylheptoxy)silane is employed for chain termination.
15 . A method, comprising modifying rubber with at least one 3-glycidyloxypropyltrialkoxysilane having long-chain alkoxy groups obtained by the process according to claim 2 .
16 . A rubber mixture, comprising a rubber modified with at least one 3-glycidyloxypropyltrialkyloxysilane having long-chain alkoxy groups obtained by the process according to claim 2 .
17 . The method according to claim 14 , comprising applying a rubber mixture comprising a solution styrene-butadiene rubber (S-SBR) or butadiene rubber (BR) modified with the composition in treads of at least one tire.
18 . The process according to claim 2 , wherein the 3-glycidyloxypropyltrialkyloxysilane having long-chain alkoxy groups is 3-glycidyloxypropyltri(-2-ethylhexoxy)silane or 3-glycidyloxypropyltri(-2-propylheptoxy)silane.
19 . The process according to claim 4 , wherein the long-chain alcohol is 2-ethylhexanol or 2-propylheptanol.