Vulcanization, as the key step in rubber process, directly affects the processing and performance of rubber products. Compared with sulfur alone, the presence of small amounts of accelerator together with sulfur can significantly improve the properties of final vulcanisate. However, the present accelerators generally pose potential risks to human health and the environment, and are suffering with their poor efficiency and sole function. Therefore, developing novel green accelerator that is non-poisonous, free or low zinc oxide content added, high-effective and multifunctional, is critical for rubber industry. This review briefly introduces the development of rubber, and the recent progresses on accelerator including the ionic liquids acceleration agents, the new bis(dithiocarbimato)zinc(II) accelerators, the rare earth vulcanizing accelerator and the novel secondary accelerators. Besides, the prospect of the in-depth study of vulcanization mechanism and the development of novel vulcanization accelerator are proposed.

Contents
1 Introduction
2 Ionic liquids vulcanization accelerators
3 Novel dithiocarbamate accelerators
4 Rare earth accelerators
4.1 Traditional rare earth accelerators
4.2 Novel zinc-free rare earth accelerators
4.3 Rare earth-transition metal multinuclear accelerators
5 New secondary accelerators
6 Conclusion and outlook