Question

Write equations for the preparation of any two polymers of the polydienes class and mention their uses.

Answer 1

Neoprene: It is prepared by the free radical addition polymerisation of chloroprene (2-chlorobuta-1, 3-diene) in the presence of a peroxide.

It is used in making hoses, gloves, shoe soles, insulating materials, etc.

Buna-S (SBR): It is a copolymer of buta-1, 3-diene and styrene. In its name Buna-S, ‘Bu’ stands for butadiene, ‘na’ for the symbol of sodium (Na), which is the polymerising agent and ‘S’ stands for styrene. It is also known as SBR, which stands for styrene butadiene rubber.

It is prepared by the addition polymerisation of a mixture of buta-1, 3-diene and styrene in an emulsion system at 273 K in the presence of a peroxide catalyst.

It can be used in the production of mechanical goods that require greater resistance to mechanical abrasion. Therefore, it is largely used in the production of automobile tyres, rubber soles, and various mechanical rubber products.