Sulfur-vulcanizable rubber compositions containing sulfur-vulcanizing agent and organic vulcanization accelerating agent are inhibited from premature vulcanization by activated methylene di (thioethers) ofthe formula
in which R is alkyl of 1-20 carbon atoms, cycloalkyl of 5-12 carbon atoms, benzyl, a-methylbenzyl, phenyl, or substituted phenyl wherein the substituents are lower alkyl, lower alkoxy, or halo, R is R or anilino or substituted anilino wherein the substituents are lower alkyl, lower alkoxy or halo, and R2 is phenyl or substituted phenyl as above;
in which R is the same as above and X is o-phenylene or straight or branched alkylene of 2-4 chain carbon atoms;
in which R is the same as above, R3 is lower alkyl or lower alkoxy, and R4 is carboalkoxy of 1-5 carbon atoms orSR
in which R is the same as above and R, is carboalkoxy of 1-5 carbon atoms, substituted carbamoyl of the formula
in which R6 is hydrogen or R, R, is R or carboalkoxy of 1-5 carbon atoms, or R6 and R7 together is alkylene or oxydialkylene of 4-8 carbon atoms which along with the nitrogen atom forms a heterocycle.
Methylene di (thioethers) having the above formulae are novel compounds.
There may also be used in the vulcanizable compositions methylene di (thioethers) in which R5 is cyano; and, provided the organic accelerating agent is 2-mercaptobenzothiazole, methylene di (thioethers) in which R4 is lower alkyl or R3 is carbamoyl.
含有
硫磺硫化剂和有机
硫化
促进剂的可
硫化橡胶组合物通过活化的亚甲基二(
硫醚)来抑制过早
硫化,其式为
其中 R 为 1-20 个碳原子的烷基、5-12 个碳原子的环烷基、苄基、a-甲基苄基、苯基或取代苯基(其中取代基为低级烷基、低级烷氧基或卤基),R 为 R 或
苯胺基或取代
苯胺基(其中取代基为低级烷基、低级烷氧基或卤基),R2 为苯基或取代苯基,如上所示;
其中 R 同上,X 为邻苯基或 2-4 链碳原子的直链或支链亚烷基;
其中 R 同上,R3 为低级烷基或低级烷氧基,R4 为 1-5 个碳原子的羧基烷氧基或 SR
其中 R 同上,R 是 1-5 个碳原子的羧基烷氧基,式中的取代
氨基甲酰基
其中 R6 是氢或 R,R, 是 R 或 1-5 个碳原子的羧基烷氧基,或 R6 和 R7 合在一起是 4-8 个碳原子的亚烷基或氧基二烷基,与氮原子一起形成杂环。
具有上述分子式的亚甲基二(
硫醚)是新型化合物。
在可
硫化组合物中还可使用 R5 为
氰基的亚甲基二
硫代
硫醚;以及 R4 为低级烷基或 R3 为
氨基甲酰基的亚甲基二
硫代
硫醚(如果有机
促进剂为
2-巯基苯并噻唑)。