Quaternary ammonium salts Quats-C₈, Quats-C₁₂, and Quats-C₁₈ with different alkyl chain lengths have been successfully synthesized, and used for modifying silk fabrics. The optimum reaction conditions of initiator concentration, curing temperature, curing time, and monomer concentration have been studied. The modified fabrics of silk-g-C₈, silk-g-C₁₂, and silk-g-C₁₈ were characterized by FTIR spectra. Antibacterial test showed that the modified silk fabrics possessed potent antibacterial activity against both Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli. The carbon number in the alkyl chain of monomers Quats-C₈, Quats-C₁₂, and Quats-C₁₈ can affect the antibacterial efficacy. With longer alkyl chain, the antibacterial efficacy increased. The quaternary ammonium salts-modified silk fabrics have small change on the tensile strength and wrinkle recovery angle, and have shown potential practical application. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43450.

The monomer 2-acrylamido-2-methyl-1-(5-methylhydantoinyl)propane (HA) was copolymerized with 3-(trimethoxysilyl)propyl methacrylate (SL) and covalently attached onto silica gel and sand particles. As a result HASL copolymer-grafted silica gel and sand particles (HASL SGPs and SPs) were obtained. These two types of HASL SGPs and SPs provided excellent biocidal efficacy against Gram positive S. aureus and Gram negative E. coli O157:H7 bacteria when the copolymer-grafted particles were exposed to dilute sodium hypochlorite (household bleach) solution. In a flowing water application, seven logs of bacteria were inactivated within 10 s of contact time with the particles packed into a column. The treated particles also exhibited good washing and storage stabilities. The chlorine loss during extensive flow could be recovered by further exposure to dilute bleach solution. The antimicrobial particles have potential application for use in inexpensive disinfecting water filters for slow water flows. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43413.

A novel monochloro-s-triazine-based N-halamine precursor, 4-(4-(5,5-dimethylhydantoin-3-ethylamino)-6-chloro-1,3,5-triazinylamino)-benzenesulfonate (HB), was synthesized and characterized by proton nuclear magnetic resonance. The reactive dyes dyeing method was applied to bond HB onto cotton fabrics, and the treated fabrics were confirmed by Fourier transform infrared spectrometer and scanning electron microscope. The chlorinated HB-treated fabrics showed excellent antibacterial efficacies against Staphylococcus aureus and Escherichia coli O157:H7 and inactivated all inoculated bacteria within 1 min of contact. Interestingly, it was found that the finishing process and following chlorination caused smaller tensile strength loss of cotton fabrics than the traditional pad-dry-cure method. Furthermore, the antimicrobial cotton fabrics exhibited good stability and regenerability. Copyright © 2015 John Wiley & Sons, Ltd.

γ-(β-Hydroxy-γ-5,5-dimethylhydatoin)-propyltriethoxysilane, a N-halamine precursor, was synthesized with 3-aminopropyltriethoxysilane and 3-glycidyl-5,5-dimethylhydantoin. The N-halamine precursor was tethered to the cotton fabric through ether linkages. The treated fabrics can be rendered excellent antimicrobial activity through a bleaching process. It can inactivate 100% of the Staphylococcus aureus and Escherichia coli O157:H7 with a contact time of 10 min and 30 min, respectively. Over 30% of the chlorine could be regained after the equivalent of 50 machine washes and rechlorination. The coatings resulted in a significant increase of hydrophobicity of cotton samples. In addition, the wrinkle recovery angle of the treated fabrics increased to some degree. Copyright © 2014 John Wiley & Sons, Ltd.

An N-halamine precursor monomer, 2,2,6,6-tetramethylpiperidinyl acrylate (TMPA), was synthesized and successfully grafted onto cotton fibers via an impregnation process (IP) and electron-beam irradiation (EB). The grafted cotton fibers could provide antibacterial efficacy after chlorination through a dilute sodium hypochlorite solution. The antibacterial efficacy was challenged against Staphylococcus aureus and Escherichia coli. The cotton fibers grafted with TMPA and acrylic acid by EB inactivated all of the bacteria within 30 min of contact, whereas the samples grafted with TMPA via an IP could not completely kill the bacteria with 60 min. The breaking strength and UVA light stability also improved significantly. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42023.

In this study, new cationic homopolymer and anionic copolymer were synthesized, and deposited onto polyglycolide sutures using a layer-by-layer assembly technique. The coated sutures were rendered antibacterial by chlorinating with dilute solution of household bleach solution at pH 7. The chlorination treatment transformed the NH groups of anionic copolymer into N-halamine structures. The N-halamine-modified sutures were challenged with Staphylococcus aureus and Escherichia coli O157:H7 bacteria at different contact times. The suture with chlorine loading of 0.22% completely inactivated both bacterial strains in 30 min contact time. Fourier transform infrared spectroscopy, scanning electron microscopy, and analytical titration confirmed the successful deposition of the N-halamine multilayers. The effect of layer-by-layer coatings of polyelectrolytes on the chlorine loading and antibacterial efficacy of sutures was evaluated. The straight-pull and knot-pull strength tests performed on the sutures reported slight decline in tensile properties after chlorination treatment. The in vitro hemolysis and cytocompatibility tests revealed that the N-halamines-based antibacterial sutures were biocompatible. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42483.

This study reports the formation of cyanuric chloride hydrolysate and its attachment onto cellulose fibers though covalent bonding. The hydrolysis product, 2,4-dichloro-6-hydroxy-1,3,5-triazine, is prepared in water solution at ambient temperature, and directly used as a treatment solution for the treatment of cotton fabrics without any prior work-up. The triazine treated fabrics are rendered antimicrobial through exposure to chlorine bleach. The oxidative chlorine bonded to the triazine-treated cotton is very stable and regenerable to standard washing tests and UVA irradiation test. The N-halamine modified cotton fabrics demonstrate excellent antimicrobial efficacy against Staphylococcus aureus ATCC 6538 and Escherichia coli O157:H7 ATCC 43895 with 7-logs reductions within the contact time of 10 and 5 min, respectively. In addition, the results of in vitro cell viability test suggested that the N-halamine modified fabrics have excellent cytocompatibility to mammalian cells. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40627.

Two N-halamine precursors, 1-glycidyl-s-triazine-2,4,6-trione and 1-(2,3-dihydroxypropyl)-s-triazine-2,4,6-trione, were synthesized and tethered onto cotton fabrics via the crosslinking agent 1,2,3,4-butanetetracarboxylic acid. The modified samples were characterized by Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope (SEM). The modified fabrics were rendered biocidal activities upon exposure to dilute hypochlorite solutions. The chlorinated cotton swatches were challenged with Staphylococcus aureus (ATCC 6538) and Escherichia coli O157:H7 (ATCC 43895) and exhibited excellent biocidal efficacy. The stability and rechargeability of the modified samples during washing and ultraviolet irradiation were also investigated. In vitro cell cytocompatibility studies demonstrated that the antibacterial cotton has good biocompatibility. Copyright © 2014 John Wiley & Sons, Ltd.

To achieve biocidal properties, a cyclic N-halamine precursor, 7,7,9,9-tetramethyl-1,3,8-triazaspiro[4.5]-decane-2,4-dione (TTDD), was synthesized and introduced into nanosized polyacrylonitrile fibrous mat by an electrospinning technique. It was rendered antimicrobial by exposure to dilute hypochlorite solution. Synthesis routes and characterization data are presented. Scanning electron microscopy (SEM) demonstrated that the ultrafine fiber possessed average diameter 414 nm (from 240 to 650 nm). The chlorinated nanofibrous composites provided about 4.9 log reductions of both Gram-positive bacteria Staphylococcus aureus (ATCC 6538) and Gram-negative bacteria Escherichia coli O157:H7 (ATCC 43895) within 5 min of contact time. This is indicative of promising possible applications in the filtration of water and air. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013