THE INTERPOLYELECTROLYTE COMPLEXES BASED ON CHITOSAN Bombyx mori AND STARCH А. Abdurasulov, N. Vokhidova, S. Rashidova Institute of Chemistry and Physics of Polymers, Tashkent, st. A. Kadyri, 7b, Republic of Uzbekistan, e-mail: abdurasulov.arslon@bk.ru Recently, the demand for interpolyelectrolyte complexes (IPEC) based on chitosan
(CS), which are effectively used in medicine, agro-industrial complexes, and other
industries, is increasing. In particular, fundamental results are being achieved in
obtaining biologically active preparations based on natural, environmentally safe
polymers [1, 2].
Based on this, interpolyelectrolyte complexes based on chitosan
Bombyx mori and corn starch were obtained,also their composition and physicochemical
features were studied.
By the conductometric titration, method to determine the composition of CS and
IPECs based on CS/starch. The hydrodynamic characteristics were studied by the
dynamic light scattering (DLS) method.
In order to establish the composition of chitosan/starch-based IPECs, the effect of
starch on the electrical conductivity of chitosan
Bombyx mori solution was researched.
For this reason, the initial electrical conductivity of a 0.05% solution of CS was
determined and the electrical conductivity of the solution was measured during titration
with a 0.05% starch solution. The result demonstrated, that the minimum conductivity
was observed in the starch titration curve when the CS/Starch = 1:0.16, mole ratio.
Consequently, in this ratio, CS amino groups are mutually compensated by the starch
functional group, tha led to decreased the electrical conductivity solutions.
The hydrodynamic radius particle of CS, starch and their stoichiometric and non-
stoichiometric IPEC was studied in their solutions. The results established, that the
particle distribution is asymmetric, which indicating the formation of particles of
different shapes and sizes.
With increasing starch content in IPEC, at all mole ratios of
CS/Starch, the sizes of nano- and microparticles increased accordingly. Perhaps, it
depends on decries in concentration of charged functional groups both polymers in the
reaction system leads to aggregation of IPEK particles from 200 nm to 650 nm.
In summary, stoichiometric and non-stoichiometric IPECs were obtained based on
chitosan and starch. When the CS/starch = 1:0.16, it was found that the macroions react in
a stoichiometric ratio, that led to toward increase the optical density of the solution and,
accordingly, the particle size IPEC.