Ion track grafting

Abstract

Radiation grafting is a well known means to change the physical and chemical properties of a polymer. Ionising particles such as ions induce in their wake through the solid a continuous trail of excitations and ionisations leading to the formation of a latent track. Radiation grafting induced by swift heavy ions ( E > 1 MeV/amu) in latent tracks is influenced by many parameters: irradiation parameters (absorbed dose, electronic stopping power), polymer substrate parameters (thickness, processing) and polymerisation parameters (monomer, grafting time). These parameters affect the polydispersity and the length of the grafted chains as well as the structure of the graft copolymer. Their influence is studied on semicrystalline polymers, the poly(vinylidene fluoride) (PVDF) and its copolymer with trifluoroethylene. A review of the results obtained in our laboratory is presented. Due to the high electronic stopping power of the particles used (from 2 to 80 MeV cm 2 mg −1), the grafting initiated by swift heavy ions is different from the one initiated with γ-rays. Moreover, the values of the grafting yield and the molecular mass distribution vary depending on the kind of ion used.