AbstractThe polymerization of styrene (St) initiated by 1,4‐dimethyl‐1,4‐diphenyl‐2‐tetrazene (1c) is studied kinetically in benzene. The polymerization proceeds through a radical mechanism. The rate equation is as follows:Rp=k[1c]0,5[St]1,0. The overall activation energy for the polymerization of St is found to be 105,9 kJ · mol−1. The efficiency of the initiator is also calculated to be 0,67. On the basis of the results, the initiating ability ofN‐methylanilino radical