The anionic polymerization of 4-vinylpyridine (4VP) has been investigated in 9/1 pyridine/THF at 0 degrees C. After characterization of the living character of 4VP polymerization, its copolymerization with tert-butyl methacrylate (tBMA) has been carried out also successfully. Their relative reactivity ratios have been determined. Solvent composition as well as temperature have been varied in order to evaluate their influence on the final molecular characteristics of the polymers. Finally, a new SEC methodology in 8/1/1 N,N-dimethylformamide/triethylamine/pyridine has been developed.