| This research focused on the regenerable antimicrobial textiles incorporated with an amine halamine compound in order to develop a high durability of the biocidal function of the modified fabric, which the previously used imide halamine compound cannot ensure. To introduce the amine halamine biocide to cellulose or cellulose-containing fabrics, a new precursor of the amine halamine, 3-methylol-2,2,5,5-tetramethylimidazolidin-4-one (MTMIO), has been synthesized by methylolation of 2,2,5,5-tetramethyl-imidazolidin-4-one (TMIO). MTMIO is then grafted onto cellulose and chlorinated through a simple bleaching process to form the biocidal amine halamine structure. The antimicrobial efficacies of the fabrics incorporated with the new amine halamine from the precursor MTMIO as well as the imide halamine from the precursor DMDMH (dimethyl-5,5-dimethylhydantoin) have been evaluated against the representative bacteria. The methods of repeated washings, extended storage and ironing at elevated temperatures were employed in the examination of the durability of biocidal function. The elemental analysis of chlorine and nitrogen were applied to quantitatively describe the change of the biocides on cellulose under the testing conditions. Also, the effects of the conditions of fabric modification, such as concentration of precursors in the finishing bath, curing temperature and time, concentration of active chlorine in the bleaching bath and pH of the bleaching solution, on the biocidal function of the finished fabrics have been discussed. Besides, the mechanical and the clothing properties of the treated fabrics have also been measured. It is found that the new amine halamine on cellulose has an effective biocidal function. Moreover, the biocidal function is far more durable than that of imide halamine under the conditions of washing, storage and ironing. Thus, the finished fabrics need less frequency of bleaching to maintain the biocidal function. In addition, the antimicrobial fabrics composed of the mixed amine halamine and imide halamine have shown the optimized biocidal efficacy and durability due to the synergistic effect between the different halamine structures, which has been verified by using UV-vis spectroscopy. |
