AbstractThe bulk copolymerization reactions of 2‐methyl‐5‐vinylpyridine(MVP) with styrene(St), methyl methacrylate(MMA), methyl acrylate(MA), and acrylonitrile(AN) at 60°C. have been investigated. The copolymer compositions were estimated by means of electrometric titrations in a nonaqueous solvent mixture.The monomer reactivity ratios of the following systems were determined: St/MVP (r1= 0.812 ± 0.005; r2= 0.91 ± 0.02), MMA/MVP (r1= 0.46 ± 0.02; r2= 0.61 ± 0.08), MA/MVP (r1= 0.172 ± 0.007; r2= 0.88 ± 0.10), and AN/MVP (r1= 0.116 ± 0.003; r2= 0.27 ± 0.04). Moreover the Q‐ and e‐values were calculated for the methyl vinylpyridine and its behavior in copolymeriz