Free Radical Mechanism

Q. SBR (GRS, Buna-S, Cold Rubber) is obtained by a free radical co-polymerisation of:

1. Buta-1, 3-diene (70%) and 30% phenyl ethane (styrene)
2. Chloroprene and styrene
3. Vinyl acetylene and styrene
4. Isoprene and 1, 3-butadiene

Q. Arrange the following steps as they occur (first to last) during the free radical mechanism of polymer formation I. Chain propagation II. Chain initiation III. Chain termination

1. I, II, III
2. II, I, III
3. III, I, II
4. I, III, II

Q. Which of the following can initiate the free radical reaction?

1. Catalyst
2. Heat
3. Light
4. All the above

Q. Difference between free radical polymerisation and ionic mechanism is reaction between carbanion and monomer

1. True
2. False