Though quaternary ammonium compounds provide

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Though quaternary ammonium compounds provide potential activity to different fi bers, it binds via ionic interactions to polyamide fabrics. Attempts have been made to overcome these problems by the use of chemical cross-linking and modifying agents (Simoncic and Tomsic 2010 ). It is worthy to note that modi fi ed quaternary ammonium compounds and composites are now used in order to get bonded to textile surfaces for simultaneously enhancing the antimicrobial property of treated textiles. 2.1.2 N -Halamines N -halamines are chlorinated products of 5,5-dimethylhydantoin and 2,2,5,5- tetramethyl-4-imidazolidinone containing one or two covalent bonds between nitrogen and a halogen atom usually chlorine (Gao and Cranston 2008 ). Chlorination of amine, amide, or imide groups in dilute sodium hypochlorite can generate nitrogen and chlorine bonds of different stability. N -halamines act as biocides for a broad spectrum of bacteria, fungi, and viruses, and this effect is based on the electrophilic substitution of chlorine in the nitrogen chlorine bond with hydrogen in the presence of water and results in the transfer of Cl + ions that can bind to acceptor regions on microorganisms and hinders enzymatic and metabolic processes, leading to the destruction of the microorganisms (Sun et al. 1995 ; Worley et al. 1988 ). N -halamines were modi fi ed or many compounds were incor- porated with them to get high durability to washing. 2.1.3 Polybiguanides Polybiguanides are polymeric polycationic amines that include cationic biguanide repeat units separated by hydrocarbon chain linkers. Polyhexamethylene biguanide 100 Shahid-ul-Islam et al.
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is widely used in medicine as an antiseptic agent, mainly used for preventing wound infection by antibiotic-resistant bacteria (Moore and Gray 2007 ; Mulder et al. 2007 ). Their remarkable biocidal activity and low toxicity have attracted attention for antimicrobial fi nishing of textiles mainly for the protection of cellulose fi bers (Blackburn et al. 2007 ; Kawabata and Taylor 2007 ; Krebs et al. 2005 ). Polyhexamethylene biguanide can bind to the anionic carboxylic groups of cellu- lose through oxidation of glucose rings during pretreatment by bleaching and mercerizing. 2.1.4 Triclosan It is a halogenated compound commonly known as triclosan 5-chloro-2- (2.4-dichlorophenoxy) phenol and has been used as a biocide in detergents and household objects, including textiles and plastics. Triclosan has been tested as antibacterial agent on cotton against Escherichia coli and Staphylococcus aureus , and simultaneously exposed to acidic, basic, and synthetic urine solutions (Orhan et al. 2007 ). It blocks lipid biosynthesis and thereby inhibits bacterial and fungal growth (Gao and Cranston 2008 ). To get the high durability to washing and to avoid leaching, triclosan is applied to fabrics in the presence of a number of cross-linking agents such as polycarboxylic acids (Guo et al. 2013 ; Yazdankhah et al. 2006 ).
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  • Fall '19
  • N. Gokarneshan

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