Synthesis and Degradation Behavior of Cyclic Poly(ε-caprolactone)

Narrow polydisersity cyclic poly(caprolactone) was synthesized by cyclization of linear α,ω-functionalized poly(caprolactone). The linear precursors were prepared via ring-opening polymerization from an azido-functionalized initiator, followed by end group modification to attach a terminal alkyne. Click coupling afforded the cyclic polymer in high yields and provided linear and cyclic poly(caprolactone) with exactly identical molecular weight distributions. The thermal and acid-catalyzed degradation of analogous linear and cyclic poly(caprolactone) samples were investigated to determine the effect of architecture.