Question

Which of the following is not a co-polymer?

• A. Buna-S rubber
• B. Neoprene rubber
• C. Bakelite
• D. Urea--Formaldehyde

Hint:

A co-polymer is formed from two or more different monomers; neoprene is formed from chloroprene only.

Answer 1

The Correct Option is B

Step 1: Understanding the Concept:
This question requires us to distinguish between homopolymers and copolymers. - A homopolymer is a polymer formed from the polymerization of a single type of monomer. - A co-polymer is a polymer formed from the polymerization of two or more different types of monomers. We need to identify the monomers for each polymer listed.
Step 2: Detailed Explanation:
Let's analyze the composition of each polymer:
(A) Buna-S rubber: This is a synthetic rubber. Its name indicates its monomers: 'Bu' for 1,3-Butadiene, 'na' for sodium (catalyst), and 'S' for Styrene. Since it is formed from two different monomers (butadiene and styrene), it is a co-polymer.
(B) Neoprene rubber: This is a synthetic rubber formed by the polymerization of the monomer chloroprene (2-chloro-1,3-butadiene). Since it is formed from only a single type of monomer, it is a homopolymer.
(C) Bakelite: This is a thermosetting plastic. It is formed by the condensation polymerization of two different monomers: Phenol and Formaldehyde. Therefore, it is a co-polymer.
(D) Urea - Formaldehyde resin: As the name suggests, this polymer is formed by the condensation reaction of two different monomers: Urea and Formaldehyde. Therefore, it is a co-polymer.
Step 3: Final Answer:
Neoprene rubber is a homopolymer, as it is made from a single monomer, chloroprene. The others are all co-polymers. Therefore, option (B) is the correct answer.