Anti-scorching agent PVI(CTP)
white powder (granules). Specific gravity 1.25-1.35. Soluble in acetone, benzene, toluene, ether, ethyl acetate, hot carbon tetrachloride, hot alcohol, slightly soluble in gasoline, insoluble in kerosene and water. Combustible.
The main application:
- PVI is a pre-vulcanized inhibitor commonly used in various sulfur bridged rubbers. The main function is to increase the safety time of the process and increase the scorch time.
- PVI is most effective in promoting sulfonamides, but it can also be used in other accelerator systems.
- Sequence of effects of PVI in various rubbers: NR> NBR> SBR> EPDM> IIR> CR.
- Most of PVI's processes in the factory, such as mixing, squeezing, extrusion (extrusion), and molding, can greatly improve the safety of the rubber to prevent scorch.
Discoloration and pollution
Non-contaminating, but slightly discolored in white and light-colored formulations.
PVI is generally used in an amount of about 0.1 - 0.4 phr. A high amount will reduce some modulus. If it is necessary to use a high amount of PVI, it is necessary to maintain the original modulus, which can improve the amount of sulfur by about 40%.
The most common is in NR formulations based on accelerator systems such as CBS. As long as 0.1 phr of PVI can be used to increase the scorch time by about 30%, about 10% of the scorch safety time can be increased in SBR.
Due to PVI and sulfur, the accelerator will react to produce some amine derivatives, and it is very difficult to dissolve in the rubber. In some formulations, there will be BLOOMING. However, as long as the dosage is below 0.6 phr, there is no such problem.
Packing and Shipping:
Package:25kg/bag ,plastic woven bag, paper with plastic film bag, kraft paper bag, or jumbo bag.