Activation of the anionic polymerization of styrene by crown tertiary amines in cyclohexane

Summary The half life time of active species propagating the anionic polymerization of styrene in the presence of tetramethyltetraazacyclotetradecane (TMTCT), is higher than the polymerization time at room temperature. The kinetic study of the propagation step measures the activating effect for a ratio at room temperature. First-order kinetics with respect to living centres is observed; the corresponding absolute rate constant is equal to 750 1. mole^–1.s^–1 at 20°C. Such an increase of the reactivity of ion-pairs is interpreted in terms of the stretching of the carbonmetal bond in polystyryllithium.