High conversion copolymerization of α-methylstyrene (α-MeSt) with N-methylmaleimide (NMeMl) or VV phenylmaleimide (NPhM1) was performed in a Calvet differential microcalorimeter under different ratios of monomer-to-monomer in the feed by using 2,2-azobis(isobutyronitrile) (AIBN) as the initiator. From a tracing of the electric signal of the calorimeter it was observed that in the presence of an excess of NMeMl or NPhMl, alternating copolymerization was the first reaction, and homopolymerization started only after the copolymerization was finished. The calorimetric method is therefore a convenient procedure for the preparation of blends of alternating copolymers with homopolymers of NMeM1 or NPhM1 of predetermined composition. Preliminary experiments indicate that based on a singleTgcriterion, blends prepared within this work are miscible.