Nitrogen‐doped graphene as an alternative to ecotoxic zinc oxide in rubbers

Zinc oxide (ZnO) is an essential ingredient in industrial rubber production; it regulates the onset of vulcanization, accelerates the kinetics of vulcanization, and improves the mechanical properties of rubber. However, environmental pollution with ZnO is a concern because it is recognized to be significantly ecotoxic and might also have adverse effects on human health. One of the major sources of ZnO environmental pollution is rubber items, tires in particular. Nitrogen (N)‐doped graphene is a promising next‐generation catalyst. We show here that the replacement of 3 phr ZnO by just 0.1 phr N‐doped graphene in styrene–butadiene rubber reduced the vulcanization onset time by more than a factor of two while retaining the fast vulcanization kinetics and enhancing the tensile strength in comparison with rubber with just ZnO. A shorter vulcanization time implies energy savings, which, together with the nontoxicity of N‐graphene, should make the resulting rubbers substantially more environmentally friendly. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46116.