SYNTHESIS OF POLY(NORBORNENE-G-EPSILON-CAPROLACTONE) COPOLYMERS BY SEQUENTIAL CONTROLLED RING-OPENING POLYMERIZATION

Poly(norbomene-g-epsilon-caprolactone) copolymers have been prepared b y the ''grafting from'' technique. Well controlled polynorbornene cont aining 5% acetate pendant groups has been firstly synthesized by ruthe nium complex-mediated ring opening metathesis polymerization. The acet ate groups have been derivatized into aluminum alkoxides by hydrolysis into alcohol followed by reaction of the alcohol with triethylaluminu m. The two polymerization steps are under complete control, so that gr aft copolymers have been synthesized with a narrow molecular weight di stribution and are free from any detectable traces of the parent homop olymers as stated by selective fractionation experiments. These origin al copolymers have been characterized by SEC, FTIR, H-1 NMR, DSC, TGA.