ナノカーボン系材料のフィラーとしての展望 カーボンナノチューブへのグラフト重合

Abstract

Recent advances in surface grafting of polymers onto nanocarbon materials, such as carbon nanotube (CNT) and vapor grown carbon nanotube (VGCF), are reviewed. The grafting of polymers onto these surfaces was achieved by (1) the “grafting onto” method and (2) “grafting from” method. For the grafting of polymers, surface functional groups, such as carboxyl groups, previously introduced onto CNT surfaces by oxidation with nitric acid, were used as grafting sites. The grafting by “grafting onto” method was carried out by the reaction of the functional groups on CNTs with terminal functional groups of polymers to give polymer-grafted CNTs. Polycondensed aromatic rings (graphene) of CNT and VGCF were used as grafting sites by using ligand-exchange reaction with polymers containing ferrocene moieties in the presence of AlCl3. The radical trapping activiity of CNT and VGCF surface was successfully used for the grafting of polymers. On the other hand, surface functional groups were converted into various initiating groups and surface initiated graft polymerization was achieved. The grafting of polymers with controlled molecular weight and narrow molecular weight distribution onto CNT by surface initiated living radical polymerization, such as atom transfer radical polymerization and nitroxide mediated radical polymerization were summarized.