The anionic polymerization of 4-vinylphenyl methyl sulfide (1), (4-vinylphenyl)methyl methyl sulfide (2), and 2-(4’-vinylphenyl)ethyl methyl sulfide (3) were carried out in THF at -78 degrees C. Monomers 1 and 3 were found to undergo anionic living polymerization with typical initiators such as lithium and potassium naphthalenides, sec-butyllithium, and sec-butyllithium capped with alpha-methylstyrene. The resulting polymers possessed molecular weights predictable from [monomer] to [initiator] ratios and narrow molecular weight distributions, the values of M-w/M-n being less than 1.1. In contrast, attempts to polymerize 2, which has a benzyl sulfide structure, failed. No appreciable polymerization occurred with 2 under the identical conditions used for the successful polymerizations of 1 and 3, For this reason, Re proposed the reaction mechanism based on a 1,6-elimination of anion, followed by the formation of the very reactive p-xylylene intermediate.