TRANSITION-METAL COMPLEXES OF N-PICOLYL POLYURETHANE

N-Picolyl polyurethanes (PUPY) were synthesized by nucleophilic substi tution. The blends of these polyurethanes with various of transition m etal chlorides [cobalt(II), nickel(II), and copper(II)] were studied b y spectroscopic and thermal analysis. Ultraviolet-visible and infrared spectroscopic evidence indicates that a tetra hedral cobalt(II) compl ex with two pendent picolyl groups in the first-shell coordination sph ere of Co2+ is formed in a series of blends with different molar ratio (from 10/1 to 2/1) of picolyl groups to cobalt(II) ions. According to the result of Small-Angle X-ray Scattering (SAXS), Differential Scann ing Calorimetry(DSC), and Dynamic Mechanical Thermal Analysis (DMTA), coordination interaction between ligands in hard segments and metal io ns provides a driving force for phase separation. The coordination str ength of pyridine with Ni2+ is stronger than Co2+ and Cu2+. (C) 1998 J ohn Wiley & Sons, Inc.