Synthesis of Carboxymethyl Chitosan and its Rheological Behaviour in Pharmaceutical and Cosmetic EmulsionsDesislava Tzaneva, Apostol Simitchiev, Nadezhda Petkova, Ventzislav Nenov, Albena Stoyanova, Panteley Denev.
The aim of the current study was synthesis and characterization of CMC and further evaluation of its emulsion stabilizing properties for preparation of pharmaceutical and cosmetic emulsions. Carboxymethyl chitosan (CMC) with high degree of substitution (50 %) has been synthesized and further characterization of resulting product by FTIR, NMR spectroscopy and thermal analysis (TGA/DTA) was carried out. CMC was also characterized as water soluble polymer with ability to give solutions with high viscosity. Rheological behavior of cosmetic emulsions prepared with 0.3 and 0.5 % CMC was investigated. Thermodynamic parameters of emulsions Gibbs free energies, enthalpies and entropies have been calculated. The current study demonstrated use of CMC as stabilizer of emulsions with potential application in pharmaceutical and cosmetic oil/water emulsions.
Key words: carboxymethyl chitosan, FTIR spectroscopy, NMR spectra, TGA, emulsions, rheological and thermodynamic properties