Biocidal quaternary ammonium salts biocides

Recently, there has been much interest in developing water-soluble tributyltin biocides to lessen the costs of application, and to prevent fire hazards when treating material in confined spaces. Bis(tributyltin) oxide itself has a very low aqueous solubility ( 0.001%), but it may be made water-dispersible by the addition of certain (534, 535) quaternary ammonium salts. Formulations of this type, although currently under development as wood preservatives (534), have been used extensively in the United Kingdom for the treatment of stonework to eradicate fungal growths, algae, mosses, and lichens (535). 

Other biocidal agents that can be used in closed industrial water systems include copper(II) salts (which, however, can cause corrosion of metals), chlorinated phenols such as sodium pentachlorophenate (NaOCfiCls, which is toxic), and quaternary ammonium salts (lUN+X-). 

Biocidal applications. The use of quaternary ammonium salts in disinfecting systems for household and industrial cleaners has been known for many years [95, 96]. Alkyl-benzyldimethyl quaternaries, alkyltrimethyl quaternaries, and dialkyldimethyl quaternaries are the more commonly used biocidal quaternary ammonium salts [16]. Recently, dialkyldimethyl quaternary ammonium salts have received renewed attention as potential wood preservatives to replace the heavy metal types [97]. Metal-free wood preservative formulations containing dialkyldimethyl ammonium salts with non-halide anions, such as carboxylates, borates, and carbonates, have been developed [98, 99]. 

Being internally neutralized, the amphoterics have minimal impact on the biocidal activity of quaternary ammonium salts. For this reason, like the nonionics, they often find use in antimicrobial preparations that are based on cationic surfactants. 

A third class of industrial chemical biocides consists of agents with the ability to inhibit biological film formation, also called surfactants . The term surfactant originates from the phrase surface active agent. Surfactants fall into four broad categories anionic (e.g., soaps, alkyl benzenesulfonates, alkyl sulfonates, alkyl phosphates), cationic (e.g., quaternary ammonium salts), nonionic (e.g., alkyl polyglycosides, alcohol ethoxylates, alkylphenol ethoxylates), and zwitterionic. 

The biocidal efficacies of N-chlorinated polymeric beads and two derivatives of polyquat (polymeric quaternary ammonium salts) beads were compared. The biocidal effects were measured after brief contact exposures of aqueous suspensions of either Staphylococcus aureus or Escherichia coli to the water-insoluble beads. The polymeric backbone was the same in all three types of... 

SYNTHESIS, CHARACTERISATION AND BIOCIDAL PROPERTIES OF EPOXY RESINS CONTAINING QUATERNARY AMMONIUM SALTS... 

A silane containing hydroxyl and quaternary ammonium salt groups was treated with a triisocyanate to prepare a biocidal film that was active against Escherichia coli for as long as 1 month.188 Cellulose was treated with the appropriate trimethoxysilane to attach a phosphonium salt.189 Polyphosphonium salts based on polystyrene have been prepared with spacers of varying lengths between the aromatic ring and the phosphorus atom.190 Polymeric dichlorohydantoins were used to disinfect potable water... 

Essential oils are active in the inhibition of Gram positive and Gram negative bacteria, yeast, and fungi. These oils usually show weak to moderate activity when compared with chemical biocides such as antibiotics, quaternary ammonium salts, or chlorinated phenols such as triclosan. When the major components are isolated, they usually show improved activity compared to the essential oils. The test methods employed commonly determine inhibition activity via an MIC, but do not usually address the issue of MLC (minimum lethal concentration) or how quickly viable organisms are reduced over a short period of time. In order to determine this, other test methods need to be employed. Differences in... 

Ciassification Quaternary ammonium salt Uses Flocculant or coagulant for effluent treatment, waste minimization programs for water-based paints, adhesives, or other aq. systems swimming pool algicide biocide for cooling towers... 

Cationic surfactants fall into several categories depending on the nature of their cationic polar heads. Some of them have functional groups susceptible to protonation e.g. amines) and thus display cationic properties particularly in acidic media, while others, such as quaternary ammonium salts, exhibit a permanent positive charge. In household products, cationic surfactants are primarily applied in fabric softeners and hair preparations. Other applications of cationic surfactants include disinfectants and biocides, emulsifiers, wetting agents and processing additives. By volume, the most important cationic surfactants in household products are the alkyl ester ammonium salts that... 

The antibacterial effects of the chemical modifications, long alkyl chains (until C12), the antibacterial activities of the quaternary ammonium salt of chitosan, and biocidal activity have also been studied and compared elsewhere. 

Biocide Prevent biological growth in storage tanks Quaternary ammonium salts, boron compounds... 

Fortuniak, W. Mazerska, U. Chojnowski, J. Basinska, T. Slomkowski, S. Chehimi, M. M. Konopacka, A. Turecka, K. Werel, W., Polysiloxanes with Quaternary Ammonium Salt Biocidal Functions and Their Behavior When Incorporated into a Silicone Elastomer Network. J. Inorg. Organomet. Polym. 2011,21,576-589. 

Nurdin N, Helary G, Sauvet G. Biocidal polymers active by contact. 11. Biological evaluation of polyurethane coatings with pendant quaternary ammonium salts. JAppl Polym Sci 1993 50 663-70. http //dx.doi.Org/10.1002/app.1993.070500411. 

Biocides are commonly used for many industrial applications, preferably in closed-circuit systems such as cooling water systems. Biocides may be divided into two main categories (a) oxidizing agents such as chlorine, ozone, and hypochlorite and (b) non-oxidizing agents such as isothiazoUnes, aldehydes, chlorophenols, and quaternary ammonium salts. 

Emulsions often contain additives that are subject to biodegradation. The destruction of biodegradable stabilizers and rheology modifiers will lead to degradation of performance properties at best and complete destabilization of the emulsion at worst. Sometimes emulsifiers with biocidal properties such those based on quaternary ammonium salts can be used in the formulations. If that is not possible, then a small amount of biocide may be required to preserve the integrity of the emulsion. When oxidative degradation is an issue, then antioxidants will also have to be part of the formulation. 

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