加硫促進劑の研究 (第44報)

Abstract

When the recipe of a rubber compound for production of rubber goods is designed with a combined use of accelerators, it is necessary to take into consideration, keeping in view the characteristics of each accelerator, such points as increase of efficiency, reduction, of production cost, safety of processing (prevention of scorching), and better quality of finished goods. It has already been made, known that the combined use of N-cyclo-hexyl-benzothiazol-2-sulphenamide (abbrev. below : CM) and diphenylgnanidine (D) or tetramethyl-thiuram-disulphide (TT) shows excellent effect of combination. The author describes in this paper the studies made, in keeping in view the above given points, on the results when with CM 2 or 3 kinds out of dibenzo-thiazol-disulphide (DM) as thiazol type accelerator, and hexamethylene-tetramine (H) as aldehyde-amine type accelerator are used.These studies have shown that, when the ratio of combination isCM : H =0.5 : 0.1 (Sample B) CM : H =0.4 : 0.2 (SampleC), the result from the point of view of scorching is not only as good as when CM alone is used (Sample A) but tensile strength as well as modulus is greater.When DM is used for a part of CM, the vulcanization velocity is great when the ratio is about CM : DM = 0.3 : 0.4 (Sample D) or CM : DM = 0.2 : 0.5 (Sample E), and the tensile strenght at the optimum cure is large in sample D, but the platean effct is inferior to sample A (CM : DM = 0.6 : 0.1). There is a tendency that the move CM is used, the tensile strength as well as modulus becomes larger.The author has been that the combined use of CM +DM+H activitates CM+DM, gives non-staining vulcanizate and shows good plateau effect.