This work aims at developing a strategy to synthesize functional cyclic copolyesters

based on the living ring-opening polymerization and the intra-molecular cross-linking reaction by UV irradiation.First

-chlorocyclohexanone was converted into -chloro--caprolactone (ClCL) in the presence of m-chloroperoxybenzoic acid (mCPBA) by the Baeyer-Villiger oxidation.Second

the quantitative polymerization of a mixture of CL and the functional monomer ClCL was initiated in toluene by 2

2-dibutyl-2-stanna-1

3-dioxepane (DSDOP) to obtain a precursor

i.e.

a living cyclic copolyesters (LCP(CLcoClCL)).The molecular weight of the precursor can be controlled by varying the molar ratio of monomer to initiator.When the comonomers were converted completely

a fresh feed of -(1-acryloyloxyethyl)--caprolactone (AECL) was added to the polymerization medium to achieve living cyclic copolyesters

poly((CLcoClCL)-b-(AECL)).Finally

the functional cyclic copolyester which is stable and free of tin dialkoxides

i.e.

cP(CLcoClCL) (Mn

NMR=32400)

was synthesized by the intramolecular photo cross-linking of few acrylic unsaturations in the close vicinity of the living cyclic chain under UV irradiation.The structures and properties of the polymers were characterized by SEC

NMR and DSC technologies.The characterization by SEC and viscosity showed that the hydrodynamic volumes of the functional cyclic copolyesters were smaller than those of their linear counterparts.DSC study showed that both the melting point and degree of crystallinity of the functional random copolyesters decreased upon cyclization.The strategy herein proposed has been successfully tested for the synthesis of cyclic copolyesters with high molecular weight and high efficiency.