Preparation and Evaluation of Antimicrobial Hyperbranched Emulsifiers for Waterborne Coatings

Nosocomial infections are a major problem in medical health care. To solve this problem, a series of antimicrobial waterborne paints were prepared by using antimicrobial hyperbranched (HB) emulsifiers. The HB-emulsifiers were prepared by polymerizing AB2 monomers obtained in a one-step reaction of bis(hexamethylene)triamine and carbonyl biscaprolactam. The blocked isocyanate end groups (B groups) of the HB-polymer were utilized to introduce tertiary amino groups through the reaction with compounds comprising either a hydroxyl or a primary amino group and a tertiary amino group. Quaternization of the tertiary amines with 6 different alkyl bromides resulted in 12 amphiphilic cationic species. The 12 emulsifiers showed the successful inhibition and killing of 8 bacterial and 2 fungal strains. The killing efficacy increased with increasing alkyl chain length. The octyl-functionalized compound was chosen for suspension polymerizations because of the good compromise between killing and emulsifying properties. W...