Synthesis of functional unsaturated polyesters using rare earth coordination catalysts, 3. Mechanistic aspects of maleic anhydride‐epichlorohydrin copolymerization with Nd[(RO)2 PO2]3/Al[CH2CH(CH3)2]3 as a catalyst

Abstract Ring‐opening alternating copolymerization of maleic anhydride and epichlorohydrin was carried out at 70°C with rare earth coordination catalysts composed of Nd[(RO)2 PO2]3 (R = CH3(CH2)3CH(C2H5)CH2)and trialkylaluminium. Anlaysis of end‐groups showed that the copolymer chain contains one OH and one CHCHCOCH2CH(CH3)2 end‐group. IR, UV‐Vis, 1H NMR and GPC results imply that a catalyst‐maleic anhyride complex is formed in the initiation step that the ring‐opening copolymerization proceeds via coordinate insertion mechanism accompanied with chain‐transfer.