A 0.16 mol dm-3 solution (3.50 cm3) of s-butyllithium in toluene was added to a solution of styrene (8.40 g) in toluene (200 cm3). After complete conversion of the styrene, isoprene (28.00 g) was added. When the isoprene had completely polymerized, the reaction was completed by addition of a 0.10 mol dm-3 solution (2.80 cm3) of dichloromethane in toluene.
Write down the reactions occurring in each stage of this reaction sequence and show the structure of the final polymer. Evaluate the relevant degrees of polymerization and the corresponding molar masses for the final polymer.