Self-Assembled and Crystallized Composites Made from Poly(ether amine) and Montmorillonite in the Presence of Copper(II) Ions

Abstract

Self-assembled and crystallized composites made from montmorillonite (MMT) by intercalation with poly(ether amine) salts and copper(II) [Cu(II)] ions simultaneously were studied. The manipulation of the silicate unit structure of the secondary (001) lattice by physically imposed osmotic pressure on the platelet interlayer was used. Divalent copper salt assisted a strong depletion effect with balancing the counterions in the clay interlayer and resulted in the extension of the dimensions of the (001) plane by increasing the spacing expansion by more than two orders of magnitude. The simultaneous adsorption of Cu(II) and intercalation of poly(oxypropylene)amine (POP) salts onto the MMT units ultimately minimized their amorphous aggregation through electrostatic attraction between the negative surface and positive edge among the silicate units. Alternatively, the attraction force through face-to-face stacking on the silicate surface is proposed, and the conformation of the POP/Cu(II) complex aligned with the approaching platelets to form orderly structures. X-ray diffraction of the MMT units exhibited a high order of reflection (i.e., (006)) in Bragg's pattern; this implied a repetitive regularity between the plate-plate distances. The high regularity disappeared when the Cu(II) adsorption exceeded the critical clay cation-exchange capacity of 1.4. The conformation of the flexible polyether backbone was altered and could no longer sustain the plate distance and the symmetric packing was destroyed when the basal spacing was decreased from 82.6 to 18.0 angstrom. (C) 2010 Wiley Periodicals, Inc. J Appl Polym Sci 19: 3437-3445, 2011