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Biocidal coatings have been used in biomedicine, cosmetology and the food industry. In this article, the coatings are described as being composed of non-stoichiometric polycomplexes, products of electrostatic coupling of two commercial biodegradable ionic polymers, anionic sodium alginate and cationic quaternized hydroxyethyl cellulose ethoxylate. Non-stoichiometric polycomplexes with a 5-fold excess of the cationic polymer were used for immobilizing hydrophobic biocidal 4-hexylresorcinol (HR). Being dispersed in water, the polycomplex particles were capable of absorbing a tenfold excess of HR in relation to the polycation. After deposition onto the plastic surface and drying, the aqueous polycomplex–HR composite formulation forms a transparent homogeneous coating, which swells slightly in water. The interpolyelectrolyte complex (IPEC) is substantially non-toxic. The incorporation of HR in the IPEC imparts antimicrobial activity to the resulting composite, in both aqueous solutions and coatings, against Gram-negative and Gram-positive bacteria and yeast. The polysaccharide-based polycomplexes with embedded HR are promising for the fabrication of biocidal films and coatings. [ABSTRACT FROM AUTHOR]

[Display omitted] Negatively charged polycomplexes have been prepared by electrostatic complexation of synthetic cationic poly(diallyldimethylammonium chloride) with excess anionic sodium alginate. These polycomplexes exhibit pronounced antimicrobial activity due to the biodegradation of the alginate matrix and the release of the biocidal polycation. The results obtained are promising for the development of simultaneously attractive and toxic polymer constructs capable of destroying microorganisms. [ABSTRACT FROM AUTHOR]

A linear anionic polysaccharide, sodium alginate, electrostatically interacts with a cationic polysaccharide, quaternized hydroxyethyl cellulose ethoxylate, in aqueous solution, thus giving an interpolyelectrolyte complex. Aqueous solutions of the initial polysaccharides and polycomplexes with an excess of the cationic or anionic polymers were used for the stabilization of soil and sand against water erosion. Physicochemical, mechanical and biological properties of the polymers and coatings were characterized by gravimetric analysis, viscosimetry, mechanical strength assessment, cell viability, and cell-mediated degradation with the following main conclusions. (a) Non-stoichiometric polycomplexes with an excess of cationic or anionic units ("cationic" and "anionic" polycomplexes, respectively) form transparent solutions or stable-in-time dispersions. (b) The complexation results in a decrease in the viscosity of polymer solutions. (c) A complete dissociation of polycomplexes to the initial components is achieved in a 0.2 M NaCl solution. (d) Soil/sand treatment with 1 wt% aqueous solutions of polymers or polycomplexes and further drying lead to the formation of strong composite coatings from polymer(s) and soil/sand particles. (e) Cationic polycomplexes form stronger coatings in comparison with anionic polycomplexes. (f) The polymer–soil coatings are stable towards re-watering, while the polymer–sand coatings show a much lower resistance to water. (g) The individual polysaccharides demonstrate a negligible toxicity to Gram-negative and Gram-positive bacteria and yeast. (h) The addition of Bacillus subtilis culture initiates the degradation of the polysaccharides and polycomplexes. (i) Films from polysaccharides and polycomplexes decompose down to small fragments after being in soil for 6 weeks. The results of the work are of importance for constructing water-resistant, low toxicity and biodegradable protective coatings for soil and sand. [ABSTRACT FROM AUTHOR]

A linear polycation, poly(diallyldimethylammonium chloride), electrostatically interacts with anionic latex particles from a carboxylated butadiene–styrene copolymer in aqueous solution thus forming an interpolyelectrolyte complex. A mutual neutralization of oppositely charged latex and polycation groups occurs at W = latex/polycation = 50 w/w ratio. At W = 27, an ultimate polycation adsorption is reached, resulting in the formation of positive polycomplex particles, while at W ˂ 27, two-component systems are formed composed of positive polycomplex particles and free polycation. A film created from the W = 12 formulation shows a high toxicity to Gram-positive and Gram-negative bacteria and yeast. Repeated washing the film leads to partial removal of polycation and a 50% decrease in the activity of the film only towards Gram-negative Pseudomonas aeruginosa. The results indicate the potential for use of the mixed polymer formulations for the fabrication of antimicrobial films and coatings. [ABSTRACT FROM AUTHOR]

We describe six aqueous formulations prepared from anionic HYPAN, an acrylic acid/acrylamide copolymer, and cationic poly(diallyldimethylammonium chloride) (PDADMAC) for stabilization of loamy sandy soil and quartz sand. The formulations were deposited on the surface of soil and sand that after drying resulted in the formation of protective polymer–soil and polymer–sand coatings. Most formulations gave mechanically stable coatings with a strength of 100–200 kg cm−2 and sustained a storm wind of 76 km h−1. A non‐stoichiometric HYPAN–PDADMAC polycomplex with a 10‐fold excess of anionic HYPAN units formed the water resistant coatings, which retained 99% soil and 90% sand. These characteristics were superior to those for coatings made from a conventional binder polyacrylamide. Additionally, the coating from soil and 'anionic' non‐stoichiometric interpolyelectrolyte complex increased the total amount of stored water and lengthened the time of water release. Anionic polymer formulations did not exhibit antimicrobial action against bacteria and yeast in both solutions and films. Cationic polymer formulations manifested strong antimicrobial action against bacteria and yeast in solutions, and suppressed the growth of Gram‐positive bacteria and yeast in films. Taking into account the commercial availability of the initial polymers and a simple procedure for polycomplex preparation, there is great potential for anionic polymer formulations as anti‐erosion binders and soil conditioners. © 2021 Society of Industrial Chemistry. [ABSTRACT FROM AUTHOR]