Studies on Non-regulated Safe Binary Accelerator System for Efficient Vulcanisation of Natural Rubber

Abstract

Nitrosamines (NA) reported to be found in rubber products vulcanized using conventional accelerators such as tetramethylthiuramdisulphide (TMTD) are carcinogenic. Tetra benzyl thiuramdisulphide (TBzTD) has been used in an efficient vulcanisation (EV) system to prepare rubber vulcanisates having properties comparable to the vulcanisate prepared using TMTD. TBzTD is reported to be non regulated and safe. The compound containing TBzTD shows better scorch safety. The novel safe vulcanisate shows comparable mechanical properties, crosslink density and improved aging resistance.

Influence of environmentally friendly curing system on properties of railway rubber pad

“…21 Nitrosamine is produced during the curing process of TMTD, which is harmful to human health, especially to vulcanization workshop workers. [22][23][24] Second, the effect of accelerator on the R d/s has not been reported in the literature. 25 Third, rubber compounds have a short scorch time, especially in the summer, and rubber compounds can be easily scorched, resulting in waste.…”

“…SEV systems could achieve optimum levels of mechanical and dynamic properties of vulcanizates with intermediate heat and reversion resistance. 24 In this work, TBSI and TB Z TD were used as accelerators. TBSI and TB Z TD serve as environmentally friendly accelerators, producing no nitrosamines during vulcanization.…”

The use of diisopropyl xanthogen polysulfide as a potential accelerator in efficient sulfur vulcanization of natural rubber compounds

“…Various attempts have been taken to eliminate or reduce the nitrosamine generation associated with traditional accelerators including the use of nitrosamine-free/ safe accelerators. 8,[11][12][13][14][15] Although nitrosamine-free xanthogen polysulfide type accelerators are probable alternatives for NR compounding, their use in commercial scale has not been reported. Stafford 16 and Beaver 17 disclosed the use of diisoamyl xanthogen tetrasulfide and diethyl xanthogen tetrasulfide in dry and synthetic rubber compounding.…”

Comparative study among TMTD, TBzTD, and ZBEC accelerators in isobutylene‐isoprene elastomer vulcanization

“…One of the main problems related to the use of some accelerators is the release of nitrosamines like N ‐nitrosodiethylamine and N ‐nitrosodimethylamine, that are classified as carcinogenic substances by international organizations and regulatory authorities, such as National Health Surveillance Agency (ANVISA‐Brazil), Registration, Evaluation, Authorization and Restriction of Chemicals (REACH‐European Union), Environmental Investigation Agency . The tetramethylthiuram disulfide (TMTD), (MM = 24,041 g mol −1 ; T m = 140 °C) is indicated as the cause of the appearance of nitrosamines, because this accelerator contains in its molecular structure groups of secondary amines …”