SYNTHESIS OF POLY(TETRAHYDROFURAN-B-EPSILON-CAPROLACTONE) MACROMONOMER VIA THE SMI2-INDUCED TRANSFORMATION

A novel well-defined macromonomer consisting of different types of monomers in polymerization mechanisms was synthesized for the first time through the SmI2-induced transformation. The macromonomer, omega-methacryloylpoly-(tetrahydrofuran-b-epsilon-caprolactone), was prepared by the reaction of methacryloyl chloride with living poly(teaahydrofuran-b-epsilon-caprolactone) [poly(THF-b-CL)] which was obtained by the two-electron reduction of the cationic growing center of poly(THF) by samarium iodide (SmI2) followed by the polymerization of CL. H-1 NMR analysis indicated the quantitative introduction of the methacryloyl group onto the polymer end. The molecular weight distribution of the macromonomer was relatively narrow, and the unit ratio of THF to CL could be controlled by both polymerization time of THF and the amount of CL, resulting from the living nature of both CL- and THF-polymerizations Radical copolymerization of the produced macromonomers with methyl methacrylate in the presence of AIBN resulted in a polymethacrylate backbone grafted with poly(THF-b-CL) block copolymers.