AbstractThe following stoichiometric vinylpyridine complexes have been prepared: (4‐VP)2—Zn(SCN)2, (2‐VP)2—Zn(SCN)2, (MVP)2—Zn(SCN)2, (MVP)2—ZnCl2, (MVP)2—ZnBr2, (MVP)2—ZnI2, and (MVP)2—HgCl2, where 4‐VP, 2‐VP, and MVP denote 4‐vinylpyridine, 2‐vinylpyridine, and 2‐methyl‐5‐vinylpyridine, respectively. Results of radical polymerization initiated by azobisisobutyronitrile indicate that the effect of complex formation between the monomers and the metal salts is to enhance the rate of polymerization with the exception of the 2‐VP complex. The Rp for the solution polymerization in dimethylformamide increases in the following order: (1) (MVP)2—Zn‐(SCN)2 > (MVP)2‐ZnCl2 > (MVP)2—ZnBr2 > (MVP)2—ZnI2 > free MVP; (2) (4‐VP)2—Zn(SCN)2 > (MVP)2—Zn(SCN)2 > free MVP > (2‐VP)2—Zn(SCN)2; and (3) MVP + Zn(CH3COO)2 < MVP + Cd(CH3COO)2. When ethanol, acetone, or tetrahydrofuran is used as solvent, the change in Rp is more marked, partly due to insolubility of the PMVP complexed with the metal salts. The increase in Rp would be attributed to the change in kp since the molecular weights of PMVP are nearly proportional to Rp when (MVP)2—ZnX2 where X is Cl−, Br−, I−, or SCN− is polymerized in DMF under fixed conditions. Copolymerizations of MVP—ZnX2 complexes (where X is Cl−, Br−, I−, or CH3COO−) with styrene indicate that the e values of complexed MVP are more positive than that of free vinylpyridine, and the amounts of the positive shift in e values increase with decreasing polarizability of the halide anions. These results are discussed in terms of the charge‐transfer properties of anions, the nature of coordination bonds, and the structures of vinylpyridines. The complexed monomers are hardly polymerized by a cationic or an anionic mechanism. Radiation‐induced solid‐state polymerization gives polymers in low yields.