Preparation and characterization of antibacterial zeolite–polyurethane composites

Abstract

In this study, antibacterial properties were induced in polyurethane (PU) films by the incorporation of Ag þ -loaded zeolites as fillers. The mechanical and thermal properties of the prepared composites were also investigated. For this purpose, two different types of zeolite microparticles, high-silica zeolite beta crystals and low-silica zeolite A crystals, were synthesized. Ag þ was added by ion exchange, and these particles were incorporated into the PU prepolymer, which was prepared from its main components of toluene diisocyanate and polypropylene ethylene glycol (medical purity). Microbiological tests revealed that both types of composites, prepared by the addition of Ag þ -containing zeolite beta or zeolite A to the PU matrix, had antibacterial properties. It was demonstrated for the first time that a high-silica zeolite (zeolite beta) and its composite film could be effectively employed as antibacterial materials. Furthermore, mechanical and thermal characterization of the composites showed that the zeolites enhanced the mechanical properties of the polymer and did not cause any deterioration in its thermal properties.

Development of durable antimicrobial surfaces containing silver- and zinc-ion–exchanged zeolites

“…Therefore, antimicrobial activity on the PP surfaces was relatively short-term in comparison to coated materials. Our data supports the findings of previous studies that reported that silver-, copper-, and zinc-ion-exchanged zeolite/polyurethane composites have antimicrobial effects against E. coli, methicillin-resistant S. aureus, P. aeruginosa, and C. tropicalis (Kamışoğlu et al, 2008;Kaali et al, 2011).…”

The influence of Ag+, Zn2+ and Cu2+ exchanged zeolite on antimicrobial and long term in vitro stability of medical grade polyether polyurethane

“…The applications of zeolite as filler in polymeric materials were previously reported in literature and proved that the antibacterial activity of these polymers was enhanced [26,27]. Furthermore the effect of zeolite content on physical and thermal properties of the polymer was also examined [26,27]. By increasing the silver-zeolite content in the polymer an increased antimicrobial activity was observed (due to the higher silver ion concentration) [22,28] but, depending on the application the zeolite content may influence physical, thermal and/or chemical properties.…”

“…The released silver ions attach to the bacteria by forming chelate complexes with the deoxyribonucleic acid (DNA) and block the transport processes in the cell [14,15]. The applications of zeolite as filler in polymeric materials were previously reported in literature and proved that the antibacterial activity of these polymers was enhanced [26,27]. Furthermore the effect of zeolite content on physical and thermal properties of the polymer was also examined [26,27].…”

Antimicrobial Biomimetics

“…Silver-containing zeolite compounds received approval of Food and Drug Administration (FDA) for being used as food contact surfaces (Joerger, 2007). Silver-zeolites have already been incorporated into polymeric films yielding antimicrobial properties (Kamisoglu et al, 2008;Zampino et al, 2008;Fernández et al, 2010). Polymer composites of plasticized poly(vinylchloride) pellets with silver zeolites demonstrated activity against S. epidermidis and E. coli (Zampino et al, 2008), while polyurethane composites with silver zeolites showed antimicrobial action against E. coli (Kamisoglu et al, 2008) and polylactid acidpolylactide (PLA)/silver zeolite composites also presented activity against S. aureus and E. coli, with silver being effectively released from the films .…”