ABSTRACT
Vulcanization is a process by which elastomeric materials or rubbers are converted into a three-dimensional network by tying together independent chain molecules. The product after vulcanization is called a vulcanizate. Vulcanizates retract forcibly to their original shape after the imposed mechanical deformation is removed. The cure curve gives a complete picture of the kinetics of vulcanization. Scorch time is measured by the time at a given temperature at which the crosslinking reactions start and there is an abrupt increase in the torque value. Since sulfur is used in the vulcanization of various diene rubbers, a decrease in the free sulfur may be followed to determine the state of cure. Badly under- or overcrosslinked vulcanizates have poor aging properties. Resistance to aging is best in the zone of optimum vulcanization. The most common vulcanizing agent for diene-containing rubber is sulfur. A vast amount of technical literature is available for sulfur vulcanization of rubber.
