Silver-containing Polymer Nanocomposites

Structure of nanocomposites based on interpolyelectrolyte complex and Ag nanoparticles, which formed by the chemical and thermochemical reduction methods from interpolyelectrolyte-metal complexes (IMC) have been investigated. It is established that chemical reduction of Ag+ ions in the pectin - Ag+ - poly(4-vinylpyridine) IMC, involving sodium borohydride at a molar ratio [Bail : [Ag+ >= 1.0 results in formation of the nanocomposite based on the pectin-poly(4-vinylpyridine)" interpolyelectrolyte complex (IPEC) and silver nanoparticles (Ag) as well. Another type of nanocomposites on the base of interpolyelectrolyte complexes pectinpolyethyleneimine (PEI)" and Ag nanoparticles was obtained by both chemical and thermochemical reduction of Ag+ ions in the polyelectrolyte-metal complexes. Such type of nanocomposites with Ag nanoparticles incorporated into polymer matrix is obtained due to the chemical reduction of Ag+ ions by NaBH4 in the interpolyelectrolyte complex, and appearance of the silver metallic phase is observed in full extent while BH4- : Ag+ molar ratio is equal to 2.0. It is defined that thermochemical reduction of Ag+ ions in IMC bulk (while films are heated to the temperature around 100 degrees C and more) results in formation of silver-containing nanocomposites. It is supposed that thermal reduction takes place owing to electrons transfer from the amino groups' nitrogen atoms of polyethyleneimine to Ag+ ions.