Chapter 12: Organocatalyzed Step-growth Polymerization

Organocatalysis has emerged in the last few years as an important tool for polymer synthesis. Extensively used in ring-opening processes, organocompounds have recently been applied to step-growth polymerizations for the synthesis of important classes of polymers, such as polyurethanes, polycarbonates, and polyesters, as well as less explored polymers, including polyethers, polycarbonates, and polybenzoins. Organocatalysts have already been shown to be good alternatives to the more commonly used organometallics, with in some cases comparable and better activities. Some of them have also demonstrated lower toxicity and easy removal in comparison with metal catalysts, which represents clear benefits especially when employing polymers in high values and sensitive fields such as bioelectronics and biomedical. Despite their wide utilization in ring-opening polymerization, less attention has been devoted to their use in step-growth polymerizations. This chapter will highlight recent advances in organocatalysis in step-growth polymerizations and focus on the step-growth polymerization catalyzed by (1) Brønsted and Lewis bases, (2) Brønsted and Lewis acids and (3) organic ionic salts.