Scorch Retarder CTP/PVI for Complex Extrusion & Thick-Section Molding: Safety & Processing Window

Oct 26, 2026 Beihua

How N-cyclohexylphthalimide (CTP/PVI) extends scorch safety for complex profiles and thick rubber goods without sacrificing final properties.

Where Scorch Bites

Complex extrusions run hot and thick-section moldings trap heat, both risking premature cure (scorch) before the part is formed.

What CTP/PVI Does

CTP-50 masterbatch delays the onset of cure (longer induction / scorch time) while the final crosslink density and physical properties stay intact when dosed correctly.

Dosage Guideline

0.2–0.5 phr, adjusted to compound, temperature and residence time. Add at the final mixing stage to avoid premature activation.

Watch Points

Too high a dose can over-delay cure and reduce throughput. Always check MDR scorch time (ts1/ts2) before production.

CTP(PVI)-80

TDS / Technical Data Sheet

Product CTP-50 / PVI Scorch Retarder
Active content 50% min. N-cyclohexylphthalimide
Carrier SBR / EPDM polymer
Appearance Pale yellow granules
Melting point 90–95°C
Loss on drying max. 1.0%
Shelf life 12 months

SDS Highlights

Low toxicity. Avoid inhalation of dust and contact with eyes. Use gloves and dust mask; keep away from strong oxidizers. Dispose of as chemical waste per local rules.

COA Sample

Batch No. CTP25-0905
CTP content 50.3% (spec. 50.0 min.)
Melting point 92.5°C
Loss on drying 0.62%
Appearance Conforms
Result PASS

Product Information

Packaging 20 kg plastic drum with aluminum foil liner; 800 kg per pallet
MOQ 200 kg (approx. 10 drums)
Shipping port Shanghai Port / Ningbo Port, China
scorch retarder CTP PVI rubber additive extrusion safety time CTP-50 masterbatch

+8613706519013