(N/A) Natural rubber,while useful,has several limitations:
$1.$ It is soft and sticky at room temperature,becomes softer at high temperatures $( > 335 \ K)$,and brittle at low temperatures $( < 283 \ K)$.
$2.$ It has a high capacity to absorb water.
$3.$ It possesses low tensile strength and low resistance to abrasion.
$4.$ It is soluble in non-polar solvents.
$5.$ It is easily attacked by oxidizing agents.
Vulcanization is performed to overcome these limitations. In this process,raw rubber is heated with sulfur and appropriate additives at a temperature range of $373 \ K$ to $415 \ K$. This creates cross-links between polymer chains,significantly improving the rubber's mechanical properties,elasticity,and durability.