1. Saratov Fall Meeting 2015 Optical activity of chitosan films with induced anisotropy Natalia O. Gegel, Anna B. Shipovskaya Research and Education Institution of Nanostructures and Biosystems, Saratov State University

2. Abstract The optical activity of chitosan films in the form of polysalt and polybase: the initial ones and those sorbed formic acid vapor, was studied. The modification of such films in formic acid vapor is shown to be accompanied by induced optical anisotropy, by varying specific optical rotation [α], and a sign inversion of [α].

3. Objects of research The films obtained from the solutions chitosan of formic acid Research methods Polarization microscopy Spectropolarimetry Experimental scheme

4. PM films prepared from aqueous formic solution of chitosan, cycle sorption-desorption vapor 56% formic acid CH-700 In the form of polysalts (S-form) Molecular weight of chitosan (CH) In the form of polybases (B-form) CH-200

5. Cycle sorption-desorption vapor 56% formic acid The dependence of the specific optical rotation [α] of the angle of orientation of the sample θ in polar coordinates Original (a) and modified (b) films CH-200 (a)(b)

6. Cycle sorption-desorption vapor 56% formic acid Original (a) and modified (b) films CH-700 (a)(b) The dependence of the specific optical rotation [α] of the angle of orientation of the sample θ in polar coordinates

7. Conclusions The optical activity of chitosan in the form of films and polisoli poliosnovaniya: initial and modified vapor of formic acid; The angular dependence (indicatrix) specific optical rotation films, the orientation angle of the sample relative to the direction of the polarization vector of the incident light beam in a plane perpendicular to the given beam; It is shown that steam treatment results in the formation of films induced optical anisotropy; It is shown that the analyzed systems are characterized by high values ​​ of specific optical rotation, indicates the formation of a cholesteric mesophase in the film by the action of formic acid vapor; Indicatrices films modified in pairs of formic acid are irregular.