Nanocomposites and nanomaterials

Preparation and physicochemical properties of polymer-polymer nanocomposites based on polyvinyl alcohol and polyaniline
Dutka V.S., Kovalskyi Ya.P., Aksimentyeva O.I., Halechko H.M.
Department of Physical and Colloid Chemistry,Ivan Franko National University of Lviv, Kyryla&Mefodia str. 6, 79005 Lviv, Ukraine
E-mail: vdutka @ukr.net

Polymer-polymer nanocomposites (PPC) have unique properties. The conductive component - polyaniline (PANI) and water-soluble polymers such as polyvinyl alcohol (PVA), polymethacrylic acid and styrene copolymer with maleic anhydride, which are part of the РРС, are of considerable interest, since they have, along with good electrical conductivity film-forming properties. The combination of such properties makes these materials promising for the formation of conductive films on surfaces of different nature.
The purpose of our work was to study the РРС based on PVА and PANI. An important advantage of such a РРС is the ease of obtaining and the ability to regulate electrical conductivity within wide limits, which is of great importance for practice. The properties of such films can be influenced by both the formation methods and the methods of obtaining PVA and PANI. One of the important properties of the РРС is their thermomechanical properties, which affect the performance and durability of the devices formed by their participation. The thermomechanical curves of PVA and PANI are of a classical nature and the glass transition temperature determined for these polymers corresponds to the literary data. Investigation of the thermomechanical properties of PPС based on PVA and PANI indicates a strong interaction between the components. Quantum-chemical calculation indicates a strong polarization of PANI molecules. Polar macromolecules of PANI can form hydrogen bonds with macromolecules PVA. IR spectroscopic studies and X-ray structural studies of the received PPC confirm intermolecular interaction between PANI and PVA.
Increasing the content of PANI in composites, as one would expect, leads to an increase in electrical conductivity. An important characteristic of the PPC based on PVA and PANI is the dependence of electrical conductivity on a temperature that is of a classical nature. According to their inclination, the activation energy of charge transfer (E) was determined for all investigated PPCs. The numerical values of E indicate that the studied PPCs are typical organic semiconductors.