Carbon Nanotubes (CNTs) chemistry is under constant evolution, as a consequence of the deep interest of the scientific community in finding new applications for these versatile materials. New and old synthetic protocols are used for improving the control of the functionalization degree of the final materials and for offering to scientists the possibility to fine-tune their final properties. In this Review, we focus the attention on radical reactions, a class of protocols characterized by small number of steps, different degrees of functionalization and enhanced solubility of the final modified CNTs, in the desired environment. The most well-known protocols are analysed providing some relevant examples appeared in the literature in the last years, monitoring the new application fields and giving insights into their mechanism in order to explain why these protocols are considered standard procedures for a wide number of scientific groups.
Keywords: Carbon nanotubes, radicals, carboxylation, diazonium salts, Birch reduction, epoxidation, polymer grafting.