This Is AuburnElectronic Theses and Dissertations

Synthesis and Application of Novel Polymeric N-halamine Antimicrobial Agents

Abstract

As one of the most effective biocides, N¬halamine biocidal coatings for surfaces have gathered a great deal of interest in recent years. In this study, several novel N¬halamine moieties were synthesized, characterized, and applied onto cotton fabric through various tethering groups and attachment techniques with the purpose of improving stabilities toward washing and ultraviolet light exposure (UVA). Five projects addressing different factors on stabilities were covered in this dissertation. In the first project, an acyclic N¬halamine precursor, 2¬amino¬2¬methyl¬1¬propanol (AMP), was applied onto cotton using 1,2,3,4¬butanetetracarboxylic acid (BTCA) as a crosslinking agent so as to impart durable press and antimicrobial functionalities simultaneously. BTCA content in the coating solution was altered to address the influence of crosslinking density on the stabilities. In the second project, a novel epoxide containing N¬halamine copolymer was synthesized, characterized, and applied onto cotton fabric. Antimicrobial efficacy, stability toward hydrolysis and UVA light exposure were evaluated along with comparison to previously synthesized epoxide-containing N¬halamine monomer. In the third project, cyclic N¬halamine rings containing amine, amide, or imide functional groups were attached to the copolymer backbone synthesized in the second project with the purpose of addressing the influence of N¬halamine chemical composition on biocidal efficacies and stabilities toward repeated laundering and UVA light exposure. In the fourth project, a vinyl N¬halamine monomer, hydantoin acrylamide, was copolymerized with a siloxane¬, an epoxide¬and a hydroxyl group¬containing monomers. These novel copolymers were immobilized onto cotton fabric through hydrolysis of alkoxy groups and formation of silyl ether bonding, opening of the epoxide ring and subsequent reaction with hydroxyl groups on cellulose, and crosslinking between the hydroxyl groups on the copolymer and on cellulose, respectively. The effect of the aforementioned tethering groups on wash fastness, UVA light exposure, and antimicrobial efficiency was addressed. In the last project, novel N¬halamine polyelectrolytes were synthesized, characterized, and coated onto cotton fabric via a layer¬by¬layer assembly technique. Feasibility of electrostatic attraction utilization for N¬halamine biocidal coatings was examined in terms of biocidal efficacy and stability to washing and sun light exposure.