What Happens to TMTD in LATZ Latex Concentrate?

Manufacturer: One of our customers is concerned about TMTD (Tetramethylthiuram Disulphide) used in the production of LATZ low-ammonia centrifuged latex concentrate and requested that we monitor the presence of TMTD in the latex. However, from our analysis we observed a declining of the level of TMTD with storage time. Some batches even show negligible level. Please explain why.

John Woon (Senior Latex Consultant): LATZ is preserved with low ammonia at 0.3% with secondary preservatives in the form of TMTD and ZnO at 0.025% each.

TMTD at this level is considered to be low when compared with TMTD used as an accelerator (at up to 1.0%) for vulcanization. Malaysian Rubber Products Research Association in the UK had done some work in the past and found that TMTD in LATZ gradually (over time) breaks down into ZDMC (Zinc Dimethyl Dithiocarbamate) and other sulphur-containing compounds.

One interesting finding was the fact that the preservation of the latex  was not affected with the "loss" of TMTD.