(1) Classification by chemical structure
Represents products M, DM, MZ. In the process of rubber vulcanization, this kind of nitrosamine products will not produce carcinogenic substances, so it is widely used, but this kind of accelerator also has its shortcomings, mainly it is easy to cause allergic reactions.
Representative products TBBS, CZ, DZ, NOBS, NS. Such additives are mainly developed by Monsanto and are widely used because of their fast curing speed and the absence of carcinogenic problems of nitrosamines. At present, it has become one of the leading rubber accelerator varieties in the world, and its total consumption accounts for more than 35% of the global accelerator consumption.
Representative products TMTD, TMTM, TETD, DPTT, etc. TMTD accelerators are still used today because of their good promotion effect and low price advantage. However, because it has been proved that the rubber products used as accelerators will produce strong carcinogenic nitrosamines during the use process, there are gradually Trend to be replaced by more environmentally friendly complex salt vulcanization accelerators such as zinc and nickel.
Representative products ZBEC, ZDC, BZ, PZ. Such products are widely used because of good scorch resistance and safe operation, and are not easy to produce nitrosamines with carcinogenic properties during use.
Representative products DIP, ZIX. This type of accelerator is mainly used for the vulcanization of latex at room temperature due to its high acceleration rate. Compared with thiuram-type vulcanizing agents, it also has the advantage of not producing carcinogenic nitrosamines. However, such accelerators have a strong odor, are polluting to the environment, and are toxic.
In addition to 5 types, there are guanidines: representative products DPG, DOTG; thioureas: representative products ETU, DETU, DPTU; aldehyde amines: representative products H, 808, and so on.
(2) Classification according to pH value
1. Acidic (Type A): thiazoles, thiurams, dithiocarbamates, xanthates.
2. Alkaline (Type B): sulfenamides, thioureas.
3. Neutral accelerators (N type): guanidines, aldehyde amines.