A dual catalyst associating InCl3 and triethylamine was found to promote controlled ring-opening polymerization of ε-decalactone (ε-DL), a monomer derived from sustainable resources. Polydecalactones (PDL) of well-defined structures with Mn up to 30 000 g/mol (Đ ~ 1.2) have been obtained free of catalytic residues under mild conditions (toluene, 3M, 60 °C, 1-20 h). Besides the typical ester end-capped PDLs, amide end groups have been installed thanks to the ability of the dual catalyst to perform with primary amines as initiators. Block PDL-b-PCL / PCLb-PDL and random P(DL-r-CL) copolymers have been also prepared by sequential and simultaneous ROP with ε-caprolactone, respectively. The absence of undesirable ASSOCIATED CONTENT Supporting Information. Electronic Supplementary Information (ESI) available: Tables containing all the ROP tests, 1 H NMR spectra of PDL dressed with different end-groups, 13 C spectra of block and random copolymers. This material is available free of charge via the Internet at http://pubs.acs.org AUTHOR INFORMATION

Polybutyrolactone tri-and di-block copolymers with well-defined structures and narrow molar distributions were prepared by trifluoromethane sulfonic acid-organocatalyzed ringopening polymerization of β-butyrolactone initiated with dihydroxylated poly(hydrogenated)butadiene and hydroxylated polystyrene. Study of the phase separation behavior of these block copolymers in the bulk and in thin film shows their ability to segregate even for low molecular weights, giving rise to spherical, cylindrical and lamellar morphologies with periodicities in the range of 10-20 nm. Estimation of the Flory-Huggins interaction parameter form the order-to-disorder transition temperatures reveals values in the same range or higher than other block copolymers associating biodegradable and polyolefin blocks