The invention relates to the production of silica reinforced rubber incorporating a novel azo-silane coupling agent which does not depend on the vulcanization reaction to effect coupling to the rubber. The novel coupling agents are of the general formula: Y -- X -- CO -- N .dbd. N -- CO -- X.sup.1 -- Z where X and X.sup.1 are the same or different and each is an imino group, an oxygen atom, or a substituted or unsubstituted methylene group; Y is a substituted or unsubstituted alkyl, aryl or aralkyl group or is the same as Z; and Z as an alkyl, aryl or aralkyl group which has an substituent at least one silane group of the formula: --Si(OR).sub.3 or --OSi(OR).sub.3 in which R is a straight or branched chain alkyl group. The azo-silane is typically used in amounts of from .1 to 10 pphr. Silica reinforced rubber vulcanizates produced using the azo-silane can have improved properties e.g. abrasion resistance, scorch resistance and resilience as compared with vulcanizates made using conventional coupling agents.
本发明涉及生产
硅增强橡胶的方法,其中包括一种新型偶氮
硅烷偶联剂,该
偶联剂不依赖于
硫化反应来使橡胶与
硅烷偶联。新型
偶联剂的一般式为:Y - X - CO - N = N - CO - X1 - Z,其中X和X1相同或不同,每个都是
亚胺基,氧原子或取代或未取代的亚甲基基团; Y是取代或未取代的烷基,芳基或芳基烷基团,或与Z相同; Z是具有至少一个
硅烷基团的烷基,芳基或芳基烷基团,该
硅烷基团的
化学式为:-Si(OR)3或-OSi(OR)3,其中R是直链或支链烷基团。通常使用偶氮
硅烷的量为0.1至10 pphr。使用偶氮
硅烷生产的
硅增强橡胶
硫化胶可以与使用传统
偶联剂制成的
硫化胶相比具有改善的性能,例如耐磨性,耐热性和回弹性。