Complexes of end-functionalized polystyrenes carrying amine end-group with transition metals: Association effects in organic solvents

Abstract

Linear end-functionalized polystyrenes of different molecular weights bearing amino end-group (NPS) were synthesized by anionic polymerization high vacuum techniques. The polymers were exposed to copper and iron salts (CuCl2.2H2O and FeCl3.6H2O) to form complexes with specific metal/amino molar ratios. The thermal stability of these complexes was studied by Thermogravimetric Analysis (TGA) and Differential Thermogravimetry (DTG), whereas their solution behavior was studied by Low Angle Laser Light Scattering (LALLS), Dynamic Light Scattering (DLS) and dilute solution Viscometry. Extended aggregation phenomena of these complexes were observed in organic solvents. The association behavior was influenced by the molecular weight of the polymer chain, the metal/amine group molar ratio, the chemical nature of the metal and the polarity of the solvent. A complex situation was revealed by DLS showing the existence of equilibrium between aggregates and clusters. Under the influence of shear forces applied in the capillary tube of the viscometer the clusters are disrupted.