Pilcure MBT is a semi ultra fast accelerator for NR, SBR, BR, NBR and other highly unsaturated diene rubbers. It readily disperses in rubber compounds and also acts as a mild peptizer for NR & CR. Pilcure MBT is a re-tarder of cure in rubber compounds accelerated using thiurams (TMTD/TMTM) / dithiocarbamates (ZDC, ZDBC) or ETU class accelerators as main accelerators. Even relatively small dosages of Pilcure MBT show significant effect and reduce bloom of thiurams and dithiocarbamates. Pilcure MBT also acts as a retarder in CR based compounding formulations.

Pilcure MBT has a long curing range and is very active above 115°C. Pilcure MBT gives flat curing characteris-tics for 'polyisoprene' rubber (e.g. NR) based compounds exhibiting ability to withstand long over cures. However, MBT accelerator is scorchy in nature and the rate and the state of cure achieved is comparatively lower than sulphenamide accelerators like CBS & TBBS. Thus, when used alone, Pilcure MBT exhibits comparatively lower tensile properties and resilience. However, in combination with other accelerators marked improvements are observed.

Normal dosages of Zinc oxide and Stearic acid are necessary as cure activators for Pilcure MBT based sulphur cure systems. Pilcure MBT when used alone shows poor response to low sulphur cure systems. However; in combination with other basic accelerators like TMTM, TMTD very low, medium or high sulphur cure systems can be designed.

Pilcure MBT based cure systems can be activated by using small proportions of basic accelerators like DOTG, DPG, TMTM, TMTD, ZDC etc. to improve the rate and the state of cure with a compromise on scorch, reversion and ageing resistance particularly when dithiocarbamate type accelerators are used as booster accelerators.

Pilcure MBT based cure systems can be retarded by using small proportions of Pilgard PVI, or other retarder like pthalic anhydride, salicylic acid, etc. Addition of extra Stearic acid or partial replacement of MBT accelerator by sulphenamide accelerator can also control scorch to some extent.

In case of low unsaturation content rubbers (e.g. IIR / EPDM) cured with thiurams and dithiocarbamate accelerators ; Pilcure MBT acts as a retarder. In EPDM based rubber compounds the dosage of Pilcure MBT is kept below 2.5 - 3.0 phr to avoid bloom of dithiocarbamate / thiurams type accelerators. Pilcure MBT is generally avoided in carbon black filled halogenated butyl rubber based stocks due to its scorching tendency; however, the same can be used in light colored Chlorobutyl based compounds for faster cure.

Pilcure MBT itself does not discolor white /colored vulcanizates, however; slight yellowing effect is observed when white colored products are exposed to sunlight. The effect of Pilcure MBT on colored products is very minimal. Pilcure MBT and other thiazole class accelerators are particularly preferred for rubber to metal bond-ing applications due to the absence of any free amines.

Pilcure MBT and its combinations with booster accelerators is extensively used in NR,SBR, NR-SBR/BR blends, NBR, IIR,EPDM and other synthetic rubber based compounds used for the manufacture of motor cycle and scooter tyres, butyl tubes, cycle tyres and tubes, beltings, retreading materials, footwear, hot air cured products, hoses, cables and miscellaneous molded and extruded rubber products.