Synthesis and Ring Opening Polymerization of a New Functional Lactone, α ‐Iodo‐ ε ‐caprolactone: A Novel Route to Functionalized Aliphatic Polyesters

A new functional lactone, α ‐iodo‐ ε ‐caprolactone ( α I ε CL), was synthesized from ε ‐caprolactone by anionic activation using a non‐nucleophilic strong base (lithium diisopropylamide) followed by an electrophilic substitution with iodine chloride. Ring‐opening (co)polymerizations of the resulting monomer with ε ‐caprolactone were carried out using tin 2‐ethylhexanoate as a catalyst in toluene at 100 °C. Homopolymerization of α I ε CL was achieved, and poly( α I ε CL) was fully characterized by SEC, 1 H NMR and elemental analysis. Random copolymerizations of α I ε CL with ε CL were controlled with experimental molecular weights close to the theoretical values, narrow molecular weight distributions and a good agreement between experimental and theoretical molar compositions of α I ε CL.