Room temperature organocatalyzed reductive depolymerization of waste polyethers, polyesters, and polycarbonates

Abstract

The reductive depolymerization of a variety of polymeric materials based on polyethers, polyesters, and polycarbonates is described using hydrosilanes as reductants and metal-free catalysts. This strategy enables the selective depolymerization of waste polymers as well as bio-based polyesters to functional chemicals such as alcohols and phenols at room temperature. Commercially available B(C6 F5)3 and [Ph3 C(+),B(C6 F5)4(-)] catalysts are active hydrosilylation catalysts in this procedure and they are compatible with the use of inexpensive and air-stable polymethylhydrosiloxane and tetramethyldisiloxane as reductants. A significant advantage of this recycling method is derived from its tolerance to the additives present in waste plastics and its ability to selectively depolymerize mixtures of polymers.

Keywords: depolymerization; homogeneous catalysis; hydrosilylation; polyesters; recycling.