A novel (main chain)-(side chain) polymeric peroxide: synthesis and initiating characteristics of poly(α-(tert-butylperoxymethyl)styrene peroxide)

Abstract

A novel (main chain)-(side chain) vinyl polyperoxide, poly(α-(tert-butylperoxymethyl)styrene peroxide) (MCSCPP), an alternating copolymer of α-(tert-butylperoxymethyl)styrene (TPMS) and oxygen, has been synthesized by the oxidative polymerization of TPMS. The MCSCPP was characterized by ¹H NMR, ¹³C NMR, IR, DSC, EI-MS, and GC-MS studies. The overall activation energy (E_a) for the degradation of MCSCPP was found to be 27 kcal/mol. Formaldehyde and α-(tert-butylperoxy)acetophenone (TPAP) were identified as the primary degradation products of MCSCPP; TPAP was found to undergo further degradation. The side chain peroxy groups were found to be thermally more stable than those in the main chain. Polymerization of styrene in the presence of MCSCPP as initiator, at 80 °C, follows classical kinetics. The presence of peroxy segments in the polystyrene chain was confirmed by both ¹H NMR and thermal decomposition studies. Interestingly, unlike other vinyl polyperoxides, the MCSCPP initiator shows an increase in molecular weight with conversion.