Questions & Answers

Explain the preparation of Buna-N with the equation.

VerifiedVerified
146.4k+ views
Hint: Buna-N is an example of a synthetic rubber. It is prepared by the copolymerization of 1,3-Butadiene and acrylonitrile. Peroxide is used as a catalyst.

Complete step by step answer:
-Buna-N is an example of a synthetic rubber.
-Synthetic rubber may be defined as any vulcanized rubber-like polymer which is capable of getting stretched to twice its length. Synthetic rubbers are either homopolymers of 1,3-butadiene or its derivatives or are copolymers of 1.3-butadiene or its derivatives with another unsaturated monomer. Buna-N is a copolymer rubber.
-Copolymerization is a technique in which two or more different compounds are allowed to polymerize. The product formed after copolymerization is called copolymers. A copolymer can be made not only by chain-growth polymerization but also by step-growth polymerization. It contains a large number of units of each monomer used in the same polymeric chain.
-1,3-Butadiene and acrylonitrile are copolymerized to form Buna-N. This copolymerization takes place in the presence of peroxide as a catalyst.
n number of 1,3-butadiene and n number of acrylonitrile reacts with each other. The double bonds shift to form a single chain. We get n number of Buna-N compounds.
The reaction of formation of Buna-N is given below:


The letter ‘N’ in Buna-N stands for acrylonitrile.
-It doesn’t get affected with the action of petrol, lubrication oil, and organic solvents. It is, therefore, used in making oil seals, hoses, and tank linings, etc.

Note:
Buna-S is also a copolymer which is prepared by the same method. It is prepared by the copolymerization between 1,3-butadiene and styrene. The letter ‘S’ in Buna-S stands for styrene.