Thereactivity of a combination of monomers depends a great deal on thenature of the polymerizing center. For example, the reactivityratios of butadiene (1) and styrene (2) are quite different in ananionic copolymerization (r1 = 5, r2 = 0.04) and in a radicalcopolymerization (r1 = 1.39, r2 = 0.78). If a copolymerization isperformed with a 50/50 mixture of the two, what are the initialcompositions of the polymers formed in the two differentcopolymerization reactions?
