Modeling the Impact of Polychloramide Solution Properties on Bacterial Disinfection Kinetics

Area of Science:

• Polymer Chemistry
• Antimicrobial Agents
• Disinfection Kinetics

Background:

• Anionic water-soluble polychloramide biocides are investigated as alternatives to cationic antimicrobial polymers.
• Anionic biocides are less prone to sequestration by non-microbial soil compared to cationic counterparts.
• Polychloramides can transfer oxidative chlorine to microbial surfaces despite electrostatic repulsion.

Purpose of the Study:

• To modify the Chick-Watson model of disinfection kinetics to incorporate polychloramide properties.
• To investigate the influence of polychloramide molecular weight (MW) and solution configuration (C*) on biocide efficacy.
• To develop a more predictive model for polychloramide-based disinfection.

Main Methods:

• Modification of the Chick-Watson model to the polymer-modified Chick-Watson (PCW) model.
• Incorporation of polychloramide molecular weight (MW) and overlap concentration (C*) into the kinetic model.
• Analysis of disinfection kinetics based on the rate of oxidative chlorine transfer.

Main Results:

• The PCW model, incorporating MW and C*, has fewer unknown parameters than the traditional Chick-Watson equation.
• The model predicts that lower MW polychloramides are more effective biocides.
• More compressed polymer configurations in solution correlate with enhanced biocidal activity.

Conclusions:

• Experimental evidence supports the PCW model's predictions regarding MW and configuration.
• Effective disinfection requires multiple transient contacts between polychloramide chains and bacterial surfaces for sufficient chlorine transfer.
• The study provides a framework for designing more effective anionic biocides.