Upcycling of Polyolefins

Upcycling of polyolefins through chemical methods offers a promising path to a sustainable plastic waste solution. Low temperature thermal pyrolysis of polyolefins has been tuned to selectively yield a solid residue with controlled molecular weight. High temperature pyrolysis yields low molecular weight polymers with functional terminal vinylidene end groups; however, the resulting functionalization from mild degradation is low. We have identified the coupling of mechanical forces, in our case sonochemistry, in tandem with mild degradation result in increased substitution of functional end groups and control of polymer molecular weight and dispersity. We further explore post-functionalization of degraded polyolefin residue with useful chemical groups such as maleic anhydride or carboxylic acid groups. Here, we describe the independent control over molecular weight and end group functionality achieved by the coupled sonochemistry and low temperature pyrolysis. This functionalized polyolefin can be used as a unit for polymerizations of other useful materials and serves as a foundation for the design of a new class of sustainable polymers.