CTP(PVI)-80 Scorch Retarder Masterbatch: Run Compounds Faster Without Premature Scorch

Scorch is one of the costliest incidents in the mixing room: a batch that crosslinks too early means rework at best and scrap at worst, and it can even clog extruders and calenders. Jiaxing Beihua CTP(PVI)-80 pre-dispersed scorch retarder masterbatch extends processing safety time while having almost no effect on cure speed or vulcanizate properties.

What Is CTP(PVI)-80?

JXBHgran CTP(PVI)-80 is a pre-dispersed scorch retarder masterbatch: 80% N-cyclohexylthiophthalimide (CTP, also known as PVI, CAS 17796-82-6) with 20% carrier and dispersing agent, supplied as granules with a density of about 1.13 g/cm³ and a 200 µm filter screen. The granular form disperses better and weighs out more easily than powder, with less dust in the weighing area.

What Problems Does It Solve?

• Delays the onset of cure: pushes back the scorch point of NR and synthetic rubbers while total cure time stays essentially unchanged.
• Safer processing: when used together with sulfenamide or thiazole accelerators, it improves processing safety without affecting vulcanizate properties.
• More durable compounds: significantly improves the storage stability of uncured compounds and their processing safety at high temperature.
• Non-staining: using this product does not cause contact staining.

Higher Temperature, Higher Speed, Higher Output

With scorch risk lowered, calenders and extruders can run at higher temperatures and higher speeds. The formulation can also safely use a stronger cure activation system, which shortens the cure cycle and raises press capacity.

Scorch-Prone Compounds Can Sometimes Be Rescued

For compounds that have been heated by summer temperatures, handling or improper operation, or that already carry scorch risk and are hard to keep processing, CTP(PVI)-80 has a certain "reversal" effect that helps restore processability. We recommend confirming with a small-batch trial first.

Dosage & Applicable Range

Three Steps to a Trial

1. Add CTP(PVI)-80 to your existing formulation (we suggest starting at 0.2–0.5 phr) and leave everything else unchanged.
2. Compare Mooney scorch time (t5) and the MDR curve (ts2, t90) to confirm that scorch time is extended and t90 is essentially unchanged.
3. Test the vulcanizate physical properties, then fine-tune the dosage against your processing temperature and speed targets.

Request a Free Sample

Tell us your rubber type, accelerator system and the scorch problem you face in processing. We will recommend a starting dosage and send you a CTP(PVI)-80 sample.