Stable vinyl polyperoxide: Synthesis, characteristics and thermal initiation potentials of poly(alpha-phenylstyrene peroxide)

The stable vinyl polyperoxide, namely, poly(alpha -phenylstyrene peroxide) (PAPSP), an alternating copolymer of alpha -phenylstyrene and oxygen, has b een synthesized by the oxidative polymerization of alpha -phenylstyrene. It was characterized by H-1 and C-13 NMR, FT-IR, DSC, GC-MS and GPC studies. The overall activation energy (E-d) for the degradation of PAPSP was found to be 45.0 kcal/mol. The stability of PAPSP was estimated from its isotherm al degradation rate and compared with other related vinyl polyperoxides. Th ermal initiating potentialities of PAPSP have been studied by polymerizing styrene at 80 degreesC. The polymerization follows classical kinetics. The mechanism of polymerization has been discussed. The active polymer, which c ontains PAPSP segments in the polystyrene chain was confirmed by H-1 NMR st udy. The values of K-2 for PAPSP compared to that of 2,5-dimethyl-2,5-dihyd roperoxyhexane and di-tert-butyl peroxide at 80 degreesC indicate that PAPS P can be used as an effective high temperature initiator.