The biocidal polymers poly[1,3-dichloro-5-methyl-5-(4‘-vinylphenyl)hydantoin] and poly[1,3-dibromo-5-methyl-5-(4‘-vinylphenyl)hydantoin] and the monochlorinated derivative have been prepared as insoluble porous beads. Halogen stability, rechargeability, and efficacy against pathogens (Staphylococcus aureus, Escherichia coli O157:H7, MS2 virus, and poliovirus) in a water filtration application have been evaluated. While the polymers previously prepared in powdered granular solid form were effective against a wide variety of pathogens in contact times of a few seconds, the flow rates of water through cartridge filters containing them were often diminished because of clogging problems. Furthermore, the fine particles could be partially aerosolized in a manufacturing facility, thus causing a potential hazard for workers in the facility. The porous beads, prepared entirely by heterogeneous reactions, overcome these limitations while maintaining outstanding biocidal efficacies. The chlorinated beads have the potential to be used for disinfecting potable water in remote areas. The brominated beads are being evaluated as biocides for use in recirculating water applications such as for spas.

A novel cyclic‐amine monomer, 1‐acryloyl‐2,2,5,5‐tetramethylimidazolidin‐4‐one (ACTMIO), was synthesized in a good yield through the reaction of acryloyl chloride with 2,2,5,5‐tetramethylimidazolidin‐4‐one and was fully characterized with Fourier transform infrared and 1H NMR studies. ACTMIO was copolymerized with several widely used acrylic and vinyl monomers under ordinary conditions. In the presence of triallyl‐1,3,5‐triazine‐2,4,6(1H,3H,5H)‐trione, ACTMIO was easily grafted onto most textile fabrics. After regular chlorine bleach treatment, N‐halamine derivatives of the corresponding polymeric materials exhibited antibacterial properties against Escherichia coli, and these properties were durable and refreshable with chlorine bleaching. The relationship between the structures and antibacterial properties of the samples is further discussed. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3073–3084, 2001

It has been demonstrated that the biocidal polymers poly-1,3-dichloro-5-methyl-5-(4‘-vinylphenyl)hydantoin and the alkali metal salt and protonated forms of its monochlorinated derivative can be prepared as insoluble porous beads by careful control of the pH in the chlorination step. While the dichloro derivative will be primarily useful in flowing water disinfection applications, particularly for potable water and recreational water, the monochloro compounds will find use in applications in which disinfection contact time is of lesser importance, such as for recirculating water treatment and odor control. Biocidal efficacy and chlorine stability data have been presented, and the potential use patterns of the several derivatives have been discussed.