What is accelerator in rubber vulcanization?

An accelerator is defined as the chemical added into a rubber compound to increase the speed of vulcanization and to permit vulcanization to proceed at lower temperature and with greater efficiency. Accelerator also Decreases the Quantity of Sulphur necessary for vulcanization and thus improving 'aged' properties of the rubber vulcanizates.

Is DCBS a sulfonamide accelerator?

Soluble in acetone organic liquids, including fats and oils, insoluble in water. DCBS is a sulfonamide accelerator with excellent anti-scorching property and delayed onset of cure. It is compatible with natural and synthetic rubbers. Suitable for radial ply tyre, rubber belts and shock absorber, etc. Particularly it produces good adhesion to metal.

What is the role of accelerator in vulcanization?

Accelerator also Decreases the Quantity of Sulphur necessary for vulcanization and thus improving 'aged' properties of the rubber vulcanizates. Accelerators are also classified as Primary and / or Secondary accelerators based on the role they play in a given compound.

How is rubber vulcanized?

Vulcanization of rubbers by sulfur alone is an extremely slow and inefficient process. The chemical reaction between sulfur and the Rubber Hydrocarbon occurs mainly at the C = C (double bonds) and each crosslink requires 40 to 55 sulphur atoms (in the absence of accelerator).

Is vulcanizate a polysulfidic cross link?

The combined sulfur with rubber exists predominantly in the ‘Polysulfidic cross links’ form and the amount of free sulfur and the ratio of free sulfur to accelerator varies from rubber to rubber. A fair degree of wasted sulphides and main chain modifications are present in the vulcanizate.

What is the mechanism of rubber vulcanization with sulfur?

Many studies have been carried out to understand the mechanism of rubber vulcanization with sulfur in the presence of accelerators and activators. Vulcanization is the phenomenon of formation of cross links with rubber macromolecules.