Ring-opening polymerization of functionalized aliphatic bicyclic carbonates

A series of six-membered bicyclic carbonates has been prepared from an alcohol precursor through esterification, etherification and silyl-etherification methods to afford functional monomers with synthetically useful vinyl, allyl, alkynyl and polymerizable groups that allow for orthogonal polymerization strategies. Anionic ring-opening polymerization (AROP) of these monomers allows us to access densely functional aliphatic polycarbonates with Mn's and Tg's in the range of 3.2-11.7 kg mol-1 and 11-106 degrees C, respectively. Bifunctional monomers comprising two separate polymerizable groups can be selectively polymerized via AROP or radical based/ring-opening metathesis polymerization methods. Selected polycarbonates were post-modified via thiol-ene chemistry to further modulate their properties. Finally, base-mediated depolymerization of these new polycarbonates was attempted giving rise to an unusual bicyclic oxetane product, which may be upcycled through appropriate copolymerization methods. The development of new functional polycarbonates through ring-opening polymerization (ROP) of cyclic precursors is described.