ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

The effect of activators on the vulcanization process. II. The effect of zinc oxide on the structure of vulcanizates

J. Beniska and B. Dogadkin

Slovak Technical University, Bratislava

Abstract: cf. C.A. 52, 15945f. The effect of ZnO (I) and stearic acid (II) on the structure of vulcanizates in mixts. with mercaptobenzothiazole on the basis of kinetics of swelling was studied. It was proven that I in the presence of II has a considerable effect on the speed and the degree of cross-linkage of vulcanizates. On the formation of cross links (S bridges) several reactions participate; immediate binding of rubber mols. with S biradicals resulting mostly in the development of polysulfide binding; the oxidation of rubber mercaptans (-SH groups) leading to mono-, di-, and polysulfide bindings and the decompn. of polysulfide bindings leading to new cross links with fewer S atoms in one cross link. The effect of I on the individual reactions varies: the first 2 are activated, the last one is retarded because I reacts with polysulfide S with the formation of ZnS.

Full paper in Portable Document Format: 126a376.pdf (in Slovak)

Chemical Papers 12 (6) 376–381 (1958)