Di-t-butyl perfumarate (DBPF) was found to induce the radical polymerizations of various vinyl monomers at 60 degrees C in benzene, although the initiation activity was considerably lower than those of dimethyl 2,2＇-azobisisobutyrate and benzoyl peroxide. The polymerizations with DBPF showed a tendency of dead-end polymerization. The polymerization of methyl methacrylate (MMA) with DBPF was kinetically studied in chlorobenzene. The initial polymerization rate (R-p) was given by R-p = k [DBPF](0.5) [MMA](1.1). The overall activation energy of the polymerization was 47 kJ/mol, a very low value. Use of this value and activation energies of propagation and termination for MMA gave an unexpectedly low activation energy (65 kJ/mol) to the decomposition of DBPF, a t-butyl perester, in the polymerization system. An ESR study on the polymerization of di-2-ethylhexyl itaconate with DBPF revealed that the observed dead-end tendency comes from the consumption of DBPF. These results suggest that the initiator efficiency of DBPF is considerably low in the present polymerization systems. Some solvent effect was observed on the polymerization of MMA with DBPF. (C) 2000 John Wiley & Sons, Inc.