Which of the following polymers are obtained by chain growth polymerization?

(A) Orlon

(B) Nylon

(C) Teflon

(D) Nylon 2 - nylon 6

(E) Dacron

Choose the correct answer from the options given below:

A, C only

The correct answer is option 2. A, C only.

Chain growth polymerization: In this process, individual monomer units add one after another to the active chain end, forming long polymer chains. This process typically involves free radicals or ionic species as initiators.

Polymer options:

1. Orlon (acrylic): Chain growth polymer formed by the free radical polymerization of acrylonitrile.

2. Nylon (polyamide): Step-growth polymer formed by the condensation reaction between diamines and diacids.

3. Teflon (polytetrafluoroethylene): Chain growth polymer formed by the radical polymerization of tetrafluoroethylene.

4. Nylon 2 - nylon 6: Not a specific polymer, but refers to different types of nylons depending on the carbon chain lengths of the diamine and diacid used. They are all step-growth polymers.

5. Dacron (polyester): Step-growth polymer formed by the condensation reaction between dicarboxylic acids and diols.

Therefore, only Orlon (A) and Teflon (C) are obtained by chain-growth polymerization. The other options, Nylon (B), Nylon 2-nylon 6 (D), and Dacron (E), are all formed by step-growth polymerization.