ESR study of radiation-chemical crosslinking of polyvinylidene fluoride in presence of imide additives☆

The ESR method has been used to study the mechanism of radiation-chemical crosslinking of PVDF in presence of N,N′-m-phenylenedimaleimide, its saturated analogue—N,N′-m-phenylene disuccinimide and N-phenylmaleimide. The nature of the radicals in PVDF, the additives and composites is analysed. In the PVDF matrix polymerization of the additives initiated by the radicals formed from them on irradiation proceeds with total conversion as compared with the 1–2% yield on polymerization of these monomers in the crystalline matrix itself. The experimental findings taken as a whole indicate that imide additives are localized in the amorphous regions of the polymer matrix of PVDF. The spatial network appearing on polymerization of N,N′-m-phenylenedimaleimide forms with the crosslinked polymer matrix a system of interpenetrating networks.