Question

Discuss the main purpose of vulcanisation of rubber.

Answer 1

$\text{Vulcanisation of rubber}$

The process of heating and mixing crude rubber with sulphur to a definite temperature for a specific time is known as vulcanization


$\text{Main purpose of vulcanisation}$

Natural rubber is useful, but its use does have problems.

The disadvantages of natural rubber are as follows:

1. The natural rubber, at room temperature, is sticky and soft. It gets even softer at elevated temperatures, greater than $335K$. It becomes brittle at low temperatures, fewer than $283K$. Therefore, natural rubber can only be used to maintain its elasticity at a temperature range of $283K-335K$.

2. Natural rubber absorbs a large amount of water.

3. Natural rubber is soluble in non-polar solvents.

4. Natural rubber is easy to attack by oxidizing agents.

To improve upon these physical properties, a process of vulcanisation is carried out.

On vulcanisation, sulphur forms cross links at the reactive sites of double bonds and thus the rubber gets stiffened