Conjugate substitution reaction of α-(halomethyl) acrylates that proceeds in addition-elimination (SN2’) mechanism is attractive for polymer chemists, because it undergoes under ambient conditions in quantitative yields to afford α-(substituted methyl) acrylates. In this report, the conjugate substitution reaction is applied to elemental reactions in polymer chemistry, including termination of stereospecific living anionic polymerization, polycondensation, and main chain scission.