replacing TBSI
replacing TBSI
(OP)
I have a formulation (NR, for thicker articles, compression moulding) where TBSI is used.
I cannot find TBSI, so I wondered if anyone knew a (possible) replacement.
I cannot find TBSI, so I wondered if anyone knew a (possible) replacement.





RE: replacing TBSI
Perhaps the nearest sulfenamide contender is the dicyclohexyl derivative, DCBS, but this is very slow curing and not very efficient in terms of crosslink density. Replacing TBSI by CBS, TBBS or MBS (assuming nitrosamines is not a problem) ought to be possible with the aid of a retarder, but maybe not PVI because this does not reduce cure rate. A more conventional retarder such as salicylic acid may be more suitable. However, no advice can really be given unless more information on the rest of the formulation, the intended application and key vulcanizate properties is provided. For instance, is the vulcanizing system a conventional high sulfur one or is it a semi EV?
I am not aware of any other commercially available sulfenimdes.
RE: replacing TBSI
The vulcanizing system is a high sulfur (2.2phr) one. The application is for thick parts which need a high crosslink density.
RE: replacing TBSI
Another possibility to ensure use of a higher cure temperature is to use a post vulcanization stabiliser such as Duralink HTS, but I have no personal experience of these.