Rubber mixtures
View Patent ↗Rubber mixtures, including at least one rubber, a filler, an organosilicon compound of the formula I one rubber accelerator and one co-accelerator. The rubber mixtures are prepared by mixing at least one rubber, a filler, an organosilicon compound of the formula I, one rubber accelerator and one co-accelerator. The rubber mixtures can be used for production of moldings. Also disclosed is a process for preparation of the organosilicon compound of the formula I via transesterification.
1. A rubber mixture, comprising
(a) at least one rubber,
(b) a filler,
(c) an organosilicon compound of general formula I,
where R is identical or different and is H, a cyclic, straight-chain or branched C 1 -C 12 -alkyl group, a carboxy group (—COOH), a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group,
R′ is identical or different and is a branched or unbranched, saturated or unsaturated, aliphatic, aromatic or mixed aliphatic/aromatic divalent C 1 -C 30 hydrocarbon group,
x is an average chain length of from 1 to 10,
(d) from 0.3 to 5% by weight of rubber accelerator, based on the rubber used, selected from the group of the thiazoles, sulphenamides, thiurams, thioureas, thiocarbonates and dithiocarbamates and
(e) an amount from 0.1 to 1.5% by weight, based on the rubber used, of co-accelerator, selected from the group of the guanidines and aldehydamines.
2. The rubber mixture according to claim 1 , further comprising a rubber auxiliary.
3. The rubber mixture according to claim 2 , wherein the rubber auxiliary is polyethylene glycol, polypropylene glycol,
polybutylene glycol with molar masses from 50 to 50 000 g/mol, hydrocarbon-terminated polyethylene glycol,
Alk-O—(CH 2 —CH 2 —O) yI —H, Alk-O(CH 2 —CH 2 —O) yI -Alk, hydrocarbon-terminated polypropylene glycol Alk-O—(CH 2 —CH(CH 3 )—O) yI —H,
Alk-O—(CH 2 —CH(CH 3 )—O) yI -Alk, hydrocarbon-terminated polybutylene glycol Alk-O—(CH 2 —CH 2 —CH 2 —CH 2 —O) yI —H,
Alk-O—(CH 2 —CH(CH 3 )—CH 2 —O) yI —H,
Alk-O—(CH 2 —CH 2 —CH 2 —CH 2 —O) yI -Alk, or
Alk-O—(CH 2 —CH(CH 3 )—CH 2 —O) yI -Alk,
where the average of yI is from 2 to 25 and Alk is a branched or unbranched, unsubstituted or substituted, saturated or unsaturated hydrocarbon having from 1 to 35 carbon atoms, or is neopentyl glycol HO—CH 2 —C(Me) 2 —CH 2 —OH, pentaerythritol C(CH 2 —OH) 4 or trimethylolpropane CH 3 —CH 2 —C(CH 2 —OH) 3 etherified with polyethylene glycol, etherified with polypropylene glycol, etherified with polybutylene glycol, or etherified with a mixture thereof, where the number of repeat units of ethylene glycol, propylene glycol or/and butylene glycol in the etherified polyalcohols is from 2 to 100.
4. A process for preparation of the rubber mixture according to claim 1 , comprising mixing together:
(a) at least one rubber,
(b) a filler,
(c) an organosilicon compound of general formula I,
(d) from 0.3 to 5% by weight of rubber accelerator, based on the rubber used, selected from the group consisting of the thiazoles, sulphenamides, thiurams, thioureas, thiocarbonates and dithiocarbamates and
(e) an amount from 0.1 to 1.5% by weight, based on the rubber used, of co-accelerator, selected from the group consisting of the guanidines and aldehydamines are mixed.
5. The process for preparation of the rubber mixture according to claim 4 , wherein mixing takes place at temperatures of from 90 to 230° C.
6. A moulding made from the rubber mixture according to claim 1 .
7. An article of manufacture selected from the group consisting of tires, tire treads, cable sheathing, hoses, drive belts, conveyor belts, roll coverings, shoe soles, sealing rings and damping elements made from the rubber mixture according to claim 1 .
8. Process for preparation of the organosilicon compounds of the formula
I— as follows
where R is identical or different and is H, a cyclic, straight-chain or branched C 1 -C 12 -alkyl group, a carboxy group (—COOH), a substituted or unsubstituted aryl group or a substituted or unsubstituted aralkyl group,
R′ is identical or different and is a branched or unbranched, saturated or unsaturated, aliphatic, aromatic or mixed aliphatic/aromatic divalent C 1 -C 30 hydrocarbon group,
x is an average chain length of from 1 to 10,
comprising:
reacting an organosilicon compounds of the formula III:
in which R′ is as defined above and alkyl is identical or different and said alkyl is a monovalent C 1 -C 8 hydrocarbon radical
in a reaction mixture with a compound of the formula IV
N(CHR—CHR—O—H) 3 IV
in which R is as defined above, with elimination of alkyl-OH, and
removing alkyl-OH from the reaction mixture,
and using a titanium alkoxide as catalyst.
9. Process according to claim 8 , wherein, for organosilicon compounds of the general formula I, where R is H, R′ is (—CH 2 —CH 2 —CH 2 —), x is from 1.5 to 2.8, an Alkyl-OH is a solvent.
10. Process according to claim 1 , wherein the amount of co-accelerator is from 0.1 to 1% by weight, based on the rubber used.
11. Process according to claim 4 , wherein the amount of co-accelerator is from 0.1 to 1% by weight, based on the rubber used.