Quaternary Ammonium Salt Groups Research Articles

Cationic hybrids from poly(N,N‐dimethylaminoethyl methacrylate) covalently crosslinked with chloroalkyl silicone derivatives effective in binding anionic dyes

ABSTRACTThe synthesis and characterization of some novel ionic organic/inorganic hybrids containing quaternary ammonium salt groups in the side chain, built on the basis of poly(N,N‐dimethylaminoethyl methacrylate), as an organic component and cation provider, and chloroalkyl‐functionalized silicone derivatives as crosslinkers and anion generators, are reported in this work. The resulted structures were investigated using Fourier transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and energy dispersive X‐ray spectroscopy. The swelling behavior of the ionic hybrids in water as a function of pH as well as the water vapor sorption capacity in dynamic regime was also studied. The cationic hybrids have a higher swelling capacity at pH 2 compared with deionized water (pH 6) due to the presence of tertiary amine groups belonging to the organic compound. The ionic organic/inorganic hybrids were tested as potential sorbents for anionic species such as dyes [e.g., methyl orange (MO)]. The equilibrium sorption capacity increased with the increase of the organic component up to around 32 mg MO/g hybrid. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016, 133, 43942.

Efficient adsorption of both methyl orange and chromium from their aqueous mixtures using a quaternary ammonium salt modified chitosan magnetic composite adsorbent

A quaternary ammonium salt modified chitosan magnetic composite adsorbent (CS-CTA-MCM) was prepared by combination of Fe3O4 nanoparticles. Various techniques were used to characterize the molecular structure, surface morphology, and magnetic feature of this composite adsorbent. CS-CTA-MCM was employed for the removal of Cr(VI) and methyl orange (MO), an anionic dye, from water in respective single and binary systems. Compared with chitosan magnetic adsorbent (CS-MCM) without modification, CS-CTA-MCM shows evidently improved adsorption capacities for both pollutants ascribed to the additional quaternary ammonium salt groups. Based on the adsorption equilibrium study, MO bears more affinity to CS-CTA-MCM than Cr(VI) causing a considerable extent of preferential adsorption of dye over metal ions in their aqueous mixture. However, at weak acidic solutions, Cr(VI) adsorption is evidently improved due to more efficient Cr(VI) forms, i.e. dichromate and monovalent chromate, binding to this chitosan-based adsorbent. Thus chromium could be efficient removal together with MO at suitable pH conditions. The adsorption isotherms and kinetics indicate that adsorptions of Cr(VI) and MO by CS-CTA-MCM both follow a homogeneous monolayer chemisorption process. This magnetic adsorbent after saturated adsorption could be rapidly separated from water and easily regenerated using dilute NaOH aqueous solutions then virtually reused with little adsorption capacity loss.

Cationic polyelectrolyte induced separation of some inorganic contaminants and their mixture (zirconium silicate, kaolin, K-feldspar, zinc oxide) as well as of the paraffin oil from water

The flocculation efficiency of a cationic polyelectrolyte with quaternary ammonium salt groups in the backbone, namely PCA5 was evaluated on zirconium silicate (kreutzonit), kaolin, K- feldspar and zinc oxide (ZnO) suspensions prepared either with each pollutant or with their mixture. The effect of several parameters such as settling time, polymer dose and the pollutant type on the separation efficacy was evaluated and followed by optical density and zeta potential measurements. Except for ZnO, the interactions between PCA5 and suspended particles led to low residual turbidity values (around 4% for kreutzonit, 5% for kaolin and 8% for K-feldspar) as well as to the reduction of flocs settling time (from 1200 min to 30 min and 120 min in case of kaolinit and K-feldspar, respectively), that meant a high efficiency in their separation. The negative value of the zeta potential and flocs size measurements, at the optimum polymer dose, point to contribution from charge patch mechanism for the particles flocculation. A good efficiency of PCA5 in separation of paraffin oil (a minimum residual turbidity of 9.8%) has been also found.

Ionic dextran derivatives for removal of Fastac 10 EC from its aqueous emulsions

Separation studies of Fastac 10 EC from model emulsions by cationic polysaccharides were followed by UV–vis spectroscopy and zeta potential measurements. Floc size measurements at the optimum polycation dose were also carried out using laser diffraction technology. The investigated polyelectrolytes contained various amounts of quaternary ammonium salt groups, N-ethyl(octyl)-N,N-dimethyl-2-hydroxypropyl ammonium chloride, attached to a dextran backbone. The effects of polycation dose, its charge density, emulsion pH and pesticide concentration on the flocculation performance were studied. The pesticide removal results (UV–vis spectroscopy) show that the optimum polycation dose decreased with increasing polymer charge density and the emulsion pH and increased with increasing pesticide concentration. The zeta potential values close to zero at the optimum polymer dose point to contribution, mainly, from charge neutralization mechanism for the flocculation process. The flocs size increase with increasing pesticide concentration was also observed.

Preparation, characterization, and antibacterial activities of quaternarizedN‐halamine‐grafted cellulose fibers

ABSTRACTA viable method for coating of cellulose fiber with quaternarized N‐halamine is reported in this article. The use of quaternary ammonium salt group in combination with N‐halamine group can reinforce the antibacterial activity. The chemical structure of as‐synthesized N‐halamine precursor 4‐(Bromo‐acetic acid methylester)‐4‐ethyl‐2‐ oxazolidinone (BEO) was characterized by1H‐NMR. The cellulose fibers were characterized by Fourier transform infrared spectra and X‐ray photoelectron spectra. The spectra data confirmed that the quaternarized N‐halamine‐grafted cellulose fibers were successfully obtained. The antibacterial properties of functional fibers were challenged with both Gram positive and Gram negative bacteria. The antibacterial tests and showed that the as‐prepared antibacterial cellulose fibers exhibited powerful and rapid bactericidal performance against both Gram negativeE. coliand Gram positiveS. aureus. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2015,132, 42702.

Fluorosilicone multi-block copolymers tethering quaternary ammonium salt groups for antimicrobial purpose

Symmetrically structured fluorosilicone multi-block copolymers containing poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(hexafluorobutyl methacrylate) (PHFBMA) were sequentially synthesized via reversible addition–fragmentation chain transfer polymerization, using a polydimethylsiloxane (PDMS) chain transfer agent with dithiocarbonate groups at both ends. Then, the CBABC-type block copolymers were quaternized with n-octyliodide to tether quaternary ammonium salt (QAS) groups in the PDMAEMA blocks for the antimicrobial use. The obtained fluorosilicone copolymers showed clear variations in the C-N+ composition and surface morphology on their films depending on the content of the PHFBMA blocks, which were characterized by X-ray photoelectron spectroscopy and atomic force microscopy, respectively. The results indicated that the symmetrical CBABC structure favored PDMS and QAS tethered blocks migrating to the film surface. With the mass percentage of the PHFBMA increased from 0 to 32.5%, the surface roughness of the copolymer film decreased gradually with a tendency to form a smooth surface. Owing to the surface properties, fluorosilicone multi-block copolymers containing a certain amount of PHFBMA with higher C-N+ content and relatively smooth morphology demonstrated obvious antimicrobial activity against Gram-positive bacteria, Bacillus subtilis and Gram-negative bacteria, Escherichia coli. The functionalized multi-block copolymers based on fluorosilicone and QAS groups would have potential applications in antimicrobial coatings.

Morphology and Mechanical Properties of Ternary Polymer Blends Containing Liquid Crystalline Ionomers with Different Ionic Group

Three side-chain liquid crystalline ionomers (SLCIs) with sulfonic group (SLCI-S), quaternary ammonium salt group (SLCI-N), and carboxylic group (SLCI-C) were synthesized by graft copolymerization upon polymethylhydrosiloxane, respectively. The SLCIs were used to blend with poly (butylene terephthalate) (PBT) and polypropylene (PP). The morphological structure and mechanical properties of the blends were investigated by scanning electron microscopy (SEM). SEM results indicated that the addition of SLCIs lead to finer and better dispersion of PP polymer in the blends relative to the blends with no SLCIs added. The compatibilization of SLCIs in the blends were in the increasing order of SLCI-S> SLCI-N> SLCI-C, which was due to the specify interaction between SLCIs and PBT increased with the increasing order of SLCI-S>SLCI-N>SLCI-C. The mechanical properties were improved when the proper amount of SLCI was added, which enabled improve adhesion at the interface. The mechanical property of PBT/PP/SLCI-S was higher than that of PBT/PP/SLCI-N, which was higher than that of PBT/PP/SLCI-C.

Microstructure and antibacterial performance of functionalized polyurethane based on polysiloxane tethered cationic biocides

The designed polyurethane containing polysiloxanes tethered quaternary ammonium salt groups exhibited special surface migrations, low surface free energy and excellent antibacterial activity towardsEscherichia coli.

Polydimethylsiloxane-polymethacrylate block copolymers tethering quaternary ammonium salt groups for antimicrobial coating

Block copolymers PDMS-b-PDMAEMA were synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization involving N,N-dimethylaminoethyl methacrylate (DMAEMA) by using poly(dimethylsiloxane) (PDMS) macro-chain transfer agent. And, the tertiary amino groups in PDMAEMA were quaternized with n-octyliodide to provide quaternary ammonium salts (QPDMAEMA). The well-defined copolymers generated composition variation and morphology evolvement on film surfaces, which were characterized by X-ray photoelectron spectroscopy, atomic force microscopy, and contact angle measurements. The results indicated that the enrichment of QPDMAEMA brought about lower elemental ratios of Si/N on the film surfaces. The surface morphologies evolved with the variations of QPDMAEMA content, and the variation trend of film roughness was exactly opposite to that of water contact angle hysteresis. With regard to structure-antimicrobial relationships, the copolymer films had more evident antimicrobial activity against Gram-positive, Bacillus subtilis, and the surfaces with heterogeneous morphology and higher N+ content presented better antimicrobial activity. The functionalized copolymers based PDMS and quaternary ammonium salts materials have the potential applications as antimicrobial coatings.

Preparation and Antimicrobial Activity of N-(2-hydroxy-3-trimethylamine) Propyl Chitosan Chloride Nanoparticles

N-(2-hydroxy-3-trimethylamine) propyl chitosan chloride (HTCC) nanoparticles were prepared through two-step method using chitosan with low molecular weight and high degree of deacetylation. H of-NH2of chitosan was replaced with quaternary ammonium salt groups to form HTCC. HTCC was further modified by ion sol-gel reaction with sodium tripolyphosphate, the reaction can be in the dispersion under the action of Span-80, and the ionic bonds formed between phosphate group of sodium tripolyphosphate and the amino group in HTCC main chain, well dispersed HTCC nanoparticles with a average diameter of 23.6nm were than obtained. The structure was characterized with fourier transform infrared spectrum (FTIR). When HTCC nanoparticles were applied to contact withstaphylococcus aureus(S.aureus) andescherichia coli(E.coli), the results showed completely under the condition of antimicrobial resistance.

Synthesis, characterization of carbon polyurethane powder and its application for separation and spectrophotometric determination of platinum in pharmaceutical and ore samples

A new chelating sorbent was synthesized by covalently linking carbon nano-fiber with ion exchange polyurethane foam (CNF-PUFIX). CNF-PUFIX was characterized using different tools e.g. elemental analysis, IR spectrum and SEM. The functional groups of PUF have disappeared. The phenolic, carboxylic, quaternary ammonium salt and tertiary amine groups are detected in the CNF-PUFIX. The sorption properties of platinum (IV) onto CNF-PUFIX were investigated, the maximum sorption of platinum ions (~100%) was at the pH ranges 4-5, shaking for 18 min and sample flow rate 1.3 mL min(-1). The experimental data was fitted by kinetic models, the pseudo-second order is predominant (R(2)=0.998), the values of h and k2 are 4.4 mmol g(-1)min(-1) and 0.15 g mmol(-1)min(-1), respectively. The sorption capacity of CNF-PUFIX and the recovery percentage of Pt (IV) were 0.19 mmol g(-1) and 99-103%, respectively (RSD=1.72%, n=5). The CNF-PUFIX could be used many times without decreasing their capacities significantly. The equilibrium process is well described by the Langmuir isotherm model (R(2)=0.857), which is attributed to the homogeneous surface structure of the CNF-PUFIX. The values of ΔG and ΔH were -3.5 and -26.1 kJ mol(-1), respectively, which indicate that the sorption of platinum onto CNF-PUFIX is spontaneous and exothermic. The lower detection limit of platinum using spectrophotometric method is 2.4 µg L(-1) (RSD~3.8%, n=6). The accuracy of the procedure was verified by the analysis of standard reference materials of pharmaceutical and granite samples.

Eco-friendly synthesis of regenerable antimicrobial polymeric resin with N-halamine and quaternary ammonium salt groups

An effective macroporous cross-linked antimicrobial polymeric resin containing N-halamine and quaternary ammonium salt moieties was synthesized in an eco-friendly and economical way. Commercially available macroporous crosslinked chloromethylated polystyrene (CMPS) resin reacted with the salt of 5,5-dimethylhydantoin (DMH) and trimethylamine (TMA) in water to produce a polymeric resin containing hydantoinyl and quaternary ammonium salt moieties, poly(p-methylstyrene)-3-(5,5-dimethylhydantoin)-co-trimethyl ammonium chloride (PSHTMA). The hydantoinyl groups in PSHTMA were converted to an antimicrobial N-halamine structure by a facile chlorination reaction in dilute NaOCl solution. The as-synthesized antimicrobial polymeric resin (Cl-PSHTMA) was characterized by FT-IR, X-ray photoelectron spectroscopy, and zeta-potential measurement. The antimicrobial tests showed that the as-synthesized antimicrobial polymeric resin was capable of 7-log inactivation of S. aureus and 8-log inactivation of E. coli within 1 minute contact time. Moreover, the N-halamine moieties in Cl-PSHTMA exhibited excellent regenerability.

Antioxidant Activity of High Molecular Weight Chitosan and N,O-Quaternized Chitosans

The objective of this study was to evaluate the in vitro antioxidant activity of high molecular weight chitosan based films. Three kinds of water-soluble quaternized chitosans with high molecular weight, namely N-(2-hydroxyl) propyl-3-trimethyl ammonium chitosan chloride (400-HTCC and 1240-HTCC), N-(2-hydroxyl) propyl-3-triethyl ammonium chitosan chloride (400-HTEC and 1240-HTEC), and O-(2-hydroxyl) propyl-3- trimethyl ammonium chitosan chloride (400-O-HTCC) were prepared from high molecular weight chitosans (400 and 1240 kDa). The in vitro antioxidant activity of a high molecular weight chitosan (1240-CS) and five quaternized chitosans was evaluated and compared as radical scavengers against 1,1-diphenyl-2-picrylhydrazyl radicals (DPPH•), hydroxyl radical (•OH), and superoxide radical (•O2(-)) using established methods, and the effect of the molecular weight, the concentration, the newly generated hydroxyl group, the extra introduced positive charge of quaternary ammonium salt group, etc., on the antioxidant activity of these high molecular weight chitosans is discussed. The data obtained in vitro models exhibited good antioxidant potency and suggested the possibility that high molecular weight chitosan based films could be effectively employed as natural antioxidant materials for application in the field of food and medicine.

Sorption preconcentration of cadmium and lead ions as complexes with unithiol on a silica surface modified by quaternary ammonium salt groups

A method of the preconcentration of cadmium and lead as complexes with 2,3-dimercaptopropane-1-sulfonic acid (Unithiol) on a silica surface with the immobilized quaternary ammonium salt groups in the dynamic mode has been developed. The conditions of preconcentration (pH, flow rate and volume of solution) and the subsequent elution of cadmium and lead by a nitric acid solution have been optimized. The proposed method allows the separation of heavy metals from the cationic matrix (Ca2+, Mg2+, Na+, K+) with the preconcentration coefficient equal to 100. The limits of detection for cadmium and lead by flame atomic-absorption spectrometry are 0.3 and 2 μg/L, respectively.

PH and reduction dual-responsive nanogel cross-linked by quaternization reaction for enhanced cellular internalization and intracellular drug delivery

A novel pH and reduction dual-responsive nanogel with improved cellular internalization was prepared through atom transfer radical polymerization and subsequent quaternization reaction. Doxorubicin (DOX), a model anticancer drug, was loaded into the nanogel via dispersion. The DOX-loaded nanogel presented a stable core-cross-linked structure under physiological conditions, but quickly released its payload in an acidic (pH 6.8) and reductive (10.0 mM glutathione) environment. Confocal fluorescence microscopy and fluorescence flow cytometry revealed that the DOX-loaded nanogel could deliver DOX into the cytoplasm and nucleus of cells, more efficiently than that of free DOX. The improved cellular internalization was more significant under acidic and reductive conditions, which was analogous to the pH and reductive conditions in endosomes and cytoplasm. In vitro cytotoxicity studies demonstrated that the pH and reduction responsive DOX-loaded nanogel could inhibit cellular proliferation more efficiently than free DOX. This dual-bioresponsive nanogel with quaternary ammonium salt group has appeared to be highly promising in the further development of intracellular drug transporters.

Equilibrium, kinetic and thermodynamic studies on perchlorate adsorption by cross-linked quaternary chitosan

Cross-linked quaternary chitosan salt (QCS) was used for perchlorate removal from aqueous solution. The effect of pH and co-existing anions on the adsorption process, adsorption isotherms, kinetics and thermodynamics was investigated. The thermo stability and the solubility in water were improved after QCS was cross-linked by glutaraldehyde. The cross-linked QCS showed maximum monolayer adsorption capacity of 119.0mg/g, which was 2.5 times higher than protonated cross-linked chitosan. The adsorption process was almost independent of pH in a range from 4.0 to 10.3, which was much wider than using protonated cross-linked chitosan with applicable pH range of 4.0–6.0. The effect from co-existing anions on perchlorate adsorption followed the order: Cl−>NO3->SO42-. The adsorption data fitted Langmuir and Tempkin isotherm models well. Adsorption kinetic analysis showed that chemical adsorption was a rate-limiting stage during the adsorption process. The adsorption reaction was exothermic and spontaneous according to the calculated result of adsorption thermodynamics. The spent adsorbents could be effectively regenerated by NaCl solution with the concentration higher than 0.3%. Fourier transformation infrared spectra and the change of Cl− concentration in solution demonstrated that the ion-exchange interaction might occur between the chloride ions on the quaternary ammonium salt groups of the cross-linked QCS and the perchlorate ions in solution, resulting in the perchlorate adsorption onto the cross-linked QCS.

Dyeing properties of novel electrolyte‐free reactive dyes on cotton fibre

A series of electrolyte‐free reactive dyes containing two quaternary ammonium salt groups as soluble moieties and one epoxy structure as the reactive group have been synthesised. The structures of the synthesised dyes were confirmed by Fourier Transform–infrared, proton nuclear magnetic resonance and elemental analysis, and their dyeing properties on cotton were studied using an electrolyte‐free dyeing process. The results indicate that electrolyte‐free reactive dyes with these structures give a high exhaustion rate, a high fixation rate and good build‐up properties on cotton. Fastness properties were, in general, also very good. The optimal dyeing process of these electrolyte‐free dyes for cotton fibre was 60 °C with 20 g/l sodium carbonate.

A new route to functional polymers: Synthesis of functional polymer-supported esters from a weak acid ion exchange resin

Treatment of Amberlite IRC-50, a weak acid cation exchange resin containing methacrylic acid residues, with tetra-n-butylammonium hydroxide or benzyltrimethylammonium hydroxide gives the corresponding polymer-supported quaternary ammonium salts. These react smoothly, in nucleophilic substitution reactions, with a range of alkyl halides or sulfonates to give side chain esters with saturated hydrocarbon groups, with quaternary ammonium or sulfonate salt groups, with halide or alcohol groups at the terminus of spacer chains, with 1,2-diol groups, with acetylenic groups or with anthracene residues. These polymer-supported species have a variety of potential applications.

Polysiloxanes With Quaternary Ammonium Salt Biocidal Functions and Their Behavior When Incorporated Into a Silicone Elastomer Network

Polysiloxanes of various structures having biocidal quaternary ammonium salt (QAS) groups pendant to the polymer chain were prepared. Their antibacterial activities were compared in aqueous solution. Selected polysiloxanes were linear polydimethylsiloxanes having 20% siloxane units substituted at silicon by 3(dimethyl-n-octylammonio)propyl chloride or 3(dimethyl-n-hexadecylammonio)propyl chloride and terminated by silanol functions at both chain ends. They were crosslinked and also incorporated by co-crosslinking into an RTV (room temperature vulcanized) silicone elastomer. Bacteriocidal activities of surfaces of the crosslinked biocidal polysiloxanes and of the elastomers having incorporated these polymers were determined by the colony count method. Thousand-fold reduction of Staphylococcus aureus in contact with the dimethyl-n-octylammonio substituted polymer was achieved in 2 min and in contact with the elastomer containing 20 wt% of this polymer in 15 min, although the density of the QAS was as low as 0.36 mmol/g. The surface structure and properties of the elastomers were studied by XPS, contact angle, AFM and model human serum protein (HSA) adsorption. Water sorption by this material was also studied. The concentration of QAS groups on the elastomer surface depended strongly on the material surroundings. No QAS was found on the surface in ultrahigh vacuum, while a strong enhancement of QAS presence on the surface was observed when it was in contact with water or water vapor. Hydrophobicity of the elastomer surface was little affected by the incorporated biocidal QAS-containing polysiloxane when the elastomer was kept in air. This material showed little ability to adsorb the HSA protein from its aqueous solution.

Combinatorial Materials Research Applied to the Development of New Surface Coatings XV: An Investigation of Polysiloxane Anti-Fouling/Fouling-Release Coatings Containing Tethered Quaternary Ammonium Salt Groups

As part of ongoing efforts aimed at the development of extensive structure−property relationships for moisture-curable polysiloxane coatings containing tethered quaternary ammonium salt (QAS) moieties for potential application as environmental friendly coatings to combat marine biofouling, a combinatorial/high-throughput (C/HT) study was conducted that was focused on four different compositional variables. The coatings that were investigated were derived from solution blends of a silanol-terminated polydimethylsiloxane (HO-PDMS-OH), QAS-functional alkoxysilane, and methyltriacetoxysilane. The compositional variables investigated were alkoxysilane functionality of the QAS-functional silane, chain length of the monovalent alkyl group attached to the QAS nitrogen atom, concentration of the QAS-functional alkoxysilane, and molecular weight of the HO-PDMS-OH. Of these variables, the composition of the alkoxysilane functionality of the QAS-functional silane was a unique variable that had not been previously investigated. The antifouling (AF) and fouling-release (FR) characteristics of the 24 unique coating compositions were characterized using HT assays based on three different marine microorganisms, namely, the two bacteria, Cellulophaga lytica and Halomonas pacifica, and the diatom, Navicula incerta. Coatings surfaces were characterized by surface energy, water contact angle hysteresis, and atomic force microscopy (AFM). A wide variety of responses were obtained over the compositional space investigated. ANOVA analysis showed that the compositional variables and their interactions significantly influenced AF/FR behaviors toward individual marine microorganisms. It was also found that utilization of the ethoxysilane-functional QASs provided enhanced AF character compared to coatings based on methoxysilane-functional analogues. This was attributed to enhanced surface segregation of QAS groups at the coating-air interface and confirmed by phase images using AFM.