Obtaining and Studying the Properties of Highly Substituted Cross-Linking with Sodium Trimetaphosphate Cationic Starches of Various Botanical Origins

Regularities are investigated and a method is developed for one-stage cationization and cross-linking of potato and corn starches using sodium trimetaphosphate as a cross-linking agent. The obtained crosslinked cationic starches retain their granular structure, while the degree of crystallinity of the samples, regardless of the temperature (20–45°C), reaction time (24–96 h), and the dose of the crosslinking agent (0.05–5.0%), is reduced insignificantly. It is shown that in a one-stage process, the efficiency of the starch phosphorylation reaction decreases with an increase in the concentration of sodium trimetaphosphate in the system, while the efficiency of the cationization reaction does not change. The rate of flocculation of kaolin suspensions increases with an increase in the dose of flocculant for all types of cationic starches. Regardless of the dose, the maximum sedimentation rates of kaolin in model systems are observed when using cross-linked cationic potato starch. The results obtained can be used to develop a technology for producing biodegradable crosslinked cationic starches with the aim of their further use in polymer flooding to increase oil recovery, and also as effective flocculants for cleaning aqueous solutions as an alternative to synthetic polyacrylamide derivatives.