ABSTRACT
The concept of a living polymerization is centralized on the idea that no chain-breaking reactions, such as transfer or termination, occur to interfere with the chain-growth process. This chapter reviews the recent developments in controlled polymerizations on p-conjugated materials, with an emphasis on poly(3-hexylthiophene) following the seminal findings by A. Yokozawa and R. D. McCullough that revolve around the utilization of Ni-mediated catalyst-transfer polycondensations. P3HT is one of the most ubiquitous p-conjugated materials used in organic photovoltaics and organic field effect transistors. These widely used materials possess desirable tunable optoelectronic properties which include excellent charge transport, broad optical absorptions, and high polarizability. Kumada catalyst transfer polymerization (KCTP) is a widely used method to obtain p-conjugated polymers. This polymerization method has been extensively studied, and many improvements have been made to modify the rates of polymerization to achieve better control. Ni(0) diffusion and disproportionation are side reactions in KCTP that can potentially reduce its living behavior by creating chain-transfer and terminations.
