Application of the zeta potential measurements to explanation of colloidal Cr2O3 stability mechanism in the presence of the ionic polyamino acids

• Published in: Colloid and polymer science Vol. 292; no. 10; pp. 2453 - 2464
• Main Authors: Ostolska, Iwona, Wiśniewska, Małgorzata
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2014; Springer
• Subjects: Aminoacid polymers; Applied sciences; Characterization and Evaluation of Materials; Chemistry; Chemistry and Materials Science; Complex Fluids and Microfluidics; Exact sciences and technology; Food Science; General and physical chemistry; Nanotechnology and Microengineering; Original Contribution; Physical Chemistry; Physicochemistry of polymers; Polymer Sciences; Soft and Granular Matter; Solid-liquid interface; Surface physical chemistry; Synthetic biopolymers; Suspension stability; Chromium (III) oxide; Polyamino acids; Zeta potential; Polymer functional groups; Turbidimetry; Polyaspartic acid; Polylysine; Liquid solid adsorption; Lysine polymer; Experimental study; Aminoacid polymer; Submicron particle; Polyelectrolyte; Aspartate polymer; Concentration effect; pH; Electrokinetic potential; Polyacid; Aqueous solution; Colloid particle; Chromium III Oxides
• ISSN: 0303-402X; 1435-1536
• DOI: 10.1007/s00396-014-3276-y

In the presented paper, the influence of the molecular weight and the type of polyamino acid functional groups on the electrokinetic properties and the stability of chromium (III) oxide suspension were examined. Analysis of the data obtained from the adsorption, potentiometric titration, zeta potential, and stability measurements allows to propose stabilization or destabilization mechanism of the studied systems. In the studies, there were used polyamino acids with different ionic characters: anionic polyaspartic acid and cationic polylysine. The measurements showed that the zeta potential depends on the concentration and molecular weight of the applied polymer. Stability of the chromium (III) oxide suspensions in the presence of ionic polyamino acids increases compared to the results obtained in the absence of polymers. The exception is LYS 4,900 at pH = 10. Under these conditions, the decrease in stability is observed due to formation of polymer bridges between the polymer chains adsorbed on different colloidal particles. Determination of the stabilization/destabilization mechanism of the polyamino acid/chromium (III) oxide system and examination of the effects of polymer molecular weight on the stabilization properties can contribute to a wider use of this group of compounds as potential stabilizers or flocculants in many industrial suspensions.