Samaneh Heidaryan - Surface Coatings and Corrosion Department, Institute of Colorants, Paints and Coatings, Hossein Abad Square, Pasdaran Street, Tehran, Iran.
Zahra Ranjbar - Surface Coatings and Corrosion Department, Institute of Colorants, Paints and Coatings, Hossein Abad Square, Pasdaran Street, Tehran, Iran.
Saeed Rastegar - Faculty of Polymer & Color Engineering, Amirkabir University of Technology, P.O. Box 15875-4413, Tehran, Iran.

Chitosan is a linear hydrophilic polysacharid obtained by deacetylation of nature chitin. It is an attractive biocompatible and nontoxic biopolymer that exhibits excellent film formingability. Moreover, it responsive to localized electrical signals, serves as an excellent candidate for electrodepositing process. Biopolymer chitosan with some primary amino group has PKa about 6.3. At lower pH most of the amino groups areprotonated making chitosan water soluble polyelectrolyte.When the pH is higher than pKa, the amino groups are deprotonated and chitosan become insoluble. This propertyallows the chitosan hydrogel to be electro assemble from an aqueous bulk solution onto a conductive surface in response tocathodic signal. Although there are increasing numbers of report on application of functional device or hybrid composite in which chitosan is electrodeposited, the mechanism by whichan electrodeposited film is formed are not well understood. In this report, we have focused on explanation of the electrodeposition behavior of chtitosan solution by different solid contents.