1,2,4-triazine suitable as a vulcanization accelerator and method for producing same
View Patent ↗A 1,2,4-triazine of formula (I): and its process of manufacture and use.
1. 1,2,4-Triazine of formula (I):
where
R 1 and R 2 independently represent H or a C 1 -C 25 hydrocarbon group chosen from linear, branched or cyclic alkyl groups and aryl groups which are optionally interrupted by one or more heteroatoms, it being possible for R 1 and R 2 to together form a ring,
R 3 represents:
a linear or branched C 1 -C 25 alkyl group which is optionally interrupted by one or more heteroatoms and which is optionally substituted by one or more cyclic C 3 -C 10 alkyl or C 6 -C 12 aryl groups, or
a cyclic C 3 -C 10 alkyl group which is optionally interrupted by one or more heteroatoms and which is optionally substituted by one or more linear, branched or cyclic C 1 -C 25 alkyl or C 6 -C 12 aryl groups which are optionally interrupted by one or more heteroatoms.
2. The 1,2,4-Triazine according to claim 1 , wherein R 1 and R 2 independently represent H, a methyl group or a phenyl group.
3. The 1,2,4-Triazine according to claim 2 , wherein R 1 or R 2 represent a phenyl group.
4. The 1,2,4-Triazine according to claim 3 , wherein R 1 represents a hydrogen and R 2 is a phenyl group.
5. The 1,2,4-Triazine according to claim 1 , wherein R 3 represents a cyclohexyl group or a tert-butyl group.
6. The 1,2,4-Triazine according to claim 1 , wherein R 3 represents a tert-butyl group.
7. A process for the preparation of a 1,2,4-triazine according to claim 1 , by oxidative coupling between
a 1,2,4-triazine-3-thiol compound of following formula (A):
where R 1 and R 2 are as defined in claim 1 , and
a primary amine of formula R 3 NH 2 , where R 3 is as defined in claim 1 ,
the oxidative coupling being carried out using a basic composition and an oxidizing compound.
8. The process according to claim 7 , comprising the steps of:
the compound (A) is reacted with the said basic composition, then
the primary amine of formula R 3 NH 2 is added to the reaction medium, then
the oxidative coupling is carried out by addition of the oxidizing compound.
9. The process according to claim 7 , comprising the steps of:
a) primary amine of formula R 3 NH 2 is reacted with the oxidizing compound, then
b) a composition comprising the basic composition, the compound of formula (A) and primary amine of formula R 3 NH 2 is added to the reaction medium obtained in stage a).
10. The process according to claim 9 , wherein R 3 is a tert-butyl group.
11. The process according to claim 7 , wherein the basic composition is an aqueous solution of an organic or inorganic base.
12. The process according to claim 11 , wherein the inorganic base is sodium hydroxide.
13. The process according to claim 7 , wherein the oxidizing compound is chosen from halogen compounds, preferably chlorine, bromine, iodine and hypohalous acids and their alkali metal salts.
14. The process according to claim 13 , wherein the oxidizing compound is sodium hypochlorite.
15. A process for preparing a composition based on one or more diene elastomers, on one or more reinforcing fillers and on a vulcanization system, comprising incorporating as a vulcanization accelerator a 1,2,4-triazine as defined in claim 1 .