Properties & Applications & PackagesInquiry

Product Overview

Cyclohexylthiophthalimide (CTP) is a reliable delayed-action anti-scorch additive used in rubber and elastomer formulations. It helps extend scorch time, reduce the risk of premature curing, and improve processing safety in high-temperature compounding and shaping operations.

N-cyclohexylthiophthalimide is also known as scorch retardant, early vulcanization inhibitor, anti-scorch agent CTP, and anti-scorch agent PVI. It is white, light yellow or light yellow-brown crystal at room temperature. The product recrystallized from n-heptane is white crystal.

Easily soluble in acetone, benzene, toluene, ether, ethyl acetate and ethyl acetate, slightly soluble in gasoline, insoluble in kerosene and water, soluble in hot carbon tetrachloride, ethanol and heptane. React cyclohexane with hydrochloric acid to form chlorinated cyclohexane. Then use sulfur for sulfurization to prepare chlorothiocyclohexane. Finally, this product is prepared by reacting phthalimide and chlorothiocyclohexane in the presence of acid absorbent.

Key Specifications

Melting Point	90°C
Boiling Point	422.6±28.0 °C(Predicted)
Density	1.25~1.35g/cm3
Refractive Index	1.7500 (estimate)
Storage Temp.	Sealed in dry,Room Temperature
Water Solubility	Insoluble in water
PKA	-2.91±0.20(Predicted)
Form	Powder to crystal
Color	White to Light yellow

Performance Benefits

Delays premature vulcanization during processing.
Improves compound safety and stability.
Helps maintain scorch resistance under demanding processing conditions.
Supports smoother extrusion and better production control.

Typical Applications

Natural rubber and synthetic rubber compounds.
Tires, hoses and technical rubber goods.
EPDM, SBR, NBR and other elastomer systems.
Rubber products requiring improved scorch resistance and processing window.

It can be used for natural rubber and synthetic rubber. It can effectively prevent the rubber material from scorching during processing and improve production efficiency. At the same time, it has a restorative effect on rubber materials that have experienced high heat or are slightly scorched. N-cyclohexylthiophthalimide is widely used in sulfur-vulcanized elastomers and has good anti-scorch effects when used with various general accelerators.

Use with the anti-scorch agent CTP, whether it is open or high-temperature rapid internal mixing, a one-stage mixing process can be used to effectively prevent scorch. It can be used together with accelerator M, DM, TMTD and effective or semi-effective vulcanization system to improve rubber properties. It can improve the production efficiency of calendering and extrusion. It is beneficial to improve the adhesion between rubber and brass-plated steel wire. It is widely used in various general-purpose rubbers and special rubbers including nitrile rubber, ethylene-propylene or EPDM rubber, butyl rubber and chloroprene rubber. During storage, avoid excessively high or too low temperatures and humidity, and store in a ventilated and dry place to avoid heat and moisture. Flammable, low toxicity.

Packaging, Grades & Supply

We supply Cyclohexylthiophthalimide (CTP) in bags, cartons and bulk packaging for industrial buyers. COA and MSDS are available with each order. For procurement teams and distributors, please ask our CTP factory for the current price and bulk supply terms based on your required volume.

Why choose Greenchem International?

Stable export supply and strict quality control.
Flexible packaging and bulk logistics support.
Technical support for rubber formulation and application selection.
Competitive commercial terms for long-term buyers.

Ordering & Inquiry

To buy Cyclohexylthiophthalimide (CTP, CAS 17796-82-6) or request COA, MSDS and a competitive quotation, please send your required grade, quantity and delivery country. We will reply with lead time and pricing.