Cellulose Acetate Membranes Modification by Aminosilane Grafting in Supercritical Carbon Dioxide towards Antibiofilm Properties

Abstract

The study explores the grafting of cellulose acetate microfiltration membranes with an aminosilane to attain antibiofilm properties. The grafting reaction was performed in the supercritical carbon dioxide used as a transport and reaction medium. The FTIR analyses and dissolution tests confirmed the covalent bonding between the aminosilane and polymer. The membranes’ microstructure was investigated using a dual-beam SEM and ion microscopy, and no adverse effects of the processing were found. The modified membranes showed a more hydrophilic nature and larger water permeate flow rate than the neat cellulose acetate membranes. The tests in a cross-filtration unit showed that modified membranes were considerably less blocked after a week of exposure to Staphylococcus aureus and Escherichia coli than the original ones. Microbiological investigations revealed strong antibiofilm properties of the grafted membranes in experiments with Staphylococcus aureus, Listeria monocytogenes, Escherichia coli, and Salmonella Enteritidis.

Cellulose Acetate Membranes: Fouling Types and Antifouling Strategies—A Brief Review

“…Surface grafting is a chemical modification, e.g., covalent bonding between the surface and a substance, leading to a change in the surface's properties [176]. For example, Tyrka et al [176] examined the potentiality of covalent bonding, an active substance covalently bonding 3-aminopropyl (diethoxy)methylsilane to the CA membrane surface in scCO 2 to obtain anti-biofouling properties. Grafting increased material hydrophilicity, as supported by contact angle results, and showed anti-biofouling solid properties.…”

Polymeric Materials Obtained by Extrusion and Injection Molding from Lignocellulosic Agroindustrial Biomass

“…Graft polymerization is a cellulose modification strategy whose purpose is to stimulate highly resistant covalent bonds to generate a branched copolymer, without affecting the primary characteristics of the biomaterial [37]. The grafting procedure drastically reduces the interaction between solutes and unattractive aggregates with the cellulolytic surface, providing groups suitable for designing electrostatic repulsion from the membrane surface or enhancing hydrophilicity to enhance water-surface interactivity [93]. The grade of the grafted polymer directly affects the properties of the natural fiber, mainly the mechanical characteristics, elasticity, potential absorption, ion exchange competence, propensity for rupture of the resistant structure with extreme conditions of temperature and abrasion, and resistance [94].…”

Cellulose Acetate-Based Materials for Water Treatment in the Context of Circular Economy

“…Fouling occurs as a result of the accumulation of chemical species on the membrane surface and translates mainly into a decrease in the flow and filtration capacity [58,65]. Since CA membranes are used in all types of membrane processes, the fouling nature varies from organic and inorganic substances to biological or colloidal aggregate species.…”