Subsequent Quaternization Research Articles

Enhancing chloride/fluoride selectivity with hydrophobic side-chain anion exchange membranes in electrodialysis

The selective separation of chloride ions (Cl−) from fluoride ions (F−) is a critical concern in various industries due to the potential risks of F− on public health and industrial operations. However, Cl−/F− separation is known to be technologically challenging, considering they have the same charge and valency. This study explores the design of anion exchange membranes (AEMs) in electrodialysis to achieve Cl−/F− separation based on the difference in their hydration energy. Poly(2,6-dimethyl-1,4-phenylene oxide) (PPO) polymers brominated at varying reaction temperatures were employed as the basic AEM material, enabling fine-tuning of the hydrophobic properties of the resulting membranes through selective bromination at the benzyl or aryl positions and the subsequent quaternization with tertiary amines of different chain lengths, ultimately enhancing their selectivity. The developed AEMs are tested in electrodialysis involving a binary Cl−/F− mixture. The obtained membranes exhibited remarkable selectivity, reaching as high as 12.5 ± 1.0, surpassing the performance of commercial monovalent selective AEMs. The results demonstrate the potential of Cl−/F− separation by electrodialysis and highlight the significance of tailored membrane design in achieving the separation of ions with the same valency.

Covalently grafting polycation to bacterial cellulose for antibacterial and anti-cell adhesive wound dressings

Hydrogel-based wound dressings are becoming increasingly important for wound healing. Bacterial cellulose (BC) has been commonly used as wound dressings due to its good in vitro and in vivo biocompatibility. However, pure BC does not possess antibacterial properties. In this regard, polycation gel was grafted onto the BC using a surface-initiated activator regenerated by electron transfer atom transfer radical polymerization (SI-ARGET ATRP) with subsequent quaternization for antibacterial wound dressing. Dimethylethyl methacrylate (DMAEMA) was successfully polymerized on the BC surface which was confirmed by Fourier transform infrared spectroscopy and elemental analysis. The morphology structure, specific surface area, pore size, and mechanical properties were also characterized. The quaternized PDMAEMA grafted on the BC endowed it with excellent antibacterial activity against E. coli (Gram-negative) and S. aureus (Gram-positive) with a killing rate of 89.2 % and 93.4 %, respectively. The number of cells was significantly reduced on QPD/BC hydrogel, demonstrating its good anti-adhesion ability. In vitro cellular evaluation revealed that the antibacterial wound dressing exhibited good biocompatibility. Overall, this study provides a feasible method to develop antibacterial and anti-cell adhesive hydrogel, which has a promising potential for wound healing.

Novel polyaryl isatin polyelectrolytes with flexible monomers for anion exchange membrane fuel cells

The stability of the anion exchange polyelectrolytes is closely tied to the durability of anion exchange membrane fuel cells. Given their excellent alkali resistance, ether-free polymer backbones have attracted considerable attention for use in anion-exchange polyelectrolytes. Herein, a series of side-chain-type poly(terphenylene-co-dibenzyl N-(6-bromohexyl)-isatin) copolymers (QAPTDBHI-n) were synthesized via superacid-catalyzed polymerization and a subsequent quaternization reaction. The cyclic cardo groups in the backbones enabled the formation of nanovoids, which facilitated ionic clusters’ self-aggregation. The introduction of flexible bibenzyl monomers provided the polymers with a spatially foldable structure, promoting the aggregation of ion clusters and strengthening interchain interactions. Compared with the membrane without flexible monomers, QAPTDBHI-n membranes exhibited higher hydroxide conductivity (>115 mS cm−1 at 80 °C), outstanding mechanical stability (tensile strength: 50.91–60.76 MPa, elongation at break: 14.27%–26.06%), and superior alkali resistance (1 M NaOH at 80°C for >1500 h and <9.5% OH− conductivity loss). Regarding fuel cell performance, the AEMFC based on QAPTDBHI-40 ionomer achieved a peak power density of 1.14 W cm−2 (H2–O2) and 0.86 W cm−2 (H2-Air, CO2 free) at 80 °C due to its higher water uptake, OH− conductivity, and lower phenyl concentration.

Main-Chain Cationic Bile Acid Polymers Mimicking Facially Amphiphilic Antimicrobial Peptides.

Antibiotic-resistant bacterial infections have led to an increased demand for antibacterial agents that do not contribute to antimicrobial resistance. Antimicrobial peptides (AMPs) with the facially amphiphilic structures have demonstrated remarkable effectiveness, including the ability to suppress antibiotic resistance during bacterial treatment. Herein, inspired by the facially amphiphilic structure of AMPs, the facially amphiphilic skeletons of bile acids (BAs) are utilized as building blocks to create a main-chain cationic bile acid polymer (MCBAP) with macromolecular facial amphiphilicity via polycondensation and a subsequent quaternization. The optimal MCBAP displays an effective activity against Gram-positive methicillin-resistant Staphylococcus aureus (MRSA) and Gram-negative Escherichia coli, fast killing efficacy, superior bactericidal stability in vitro, and potent anti-infectious performance in vivo using the MRSA-infected wound model. MCBAP shows the low possibility to develop drug-resistant bacteria after repeated exposure, which may ascribe to the macromolecular facial amphiphilicity promoting bacterial membrane disruption and the generation of reactive oxygen species. The easy synthesis and low cost of MCBAP, the superior antimicrobial performance, and the therapeutic potential in treating MRSA infection altogether demonstrate that BAs are a promising group of building blocks to mimic the facially amphiphilic structure of AMPs in treating MRSA infection and alleviating antibiotic resistance.

Photocured Poly(Mannitol Sebacate) with Functional Methacrylic Monomer: Analysis of Physical, Chemical, and Biological Properties.

In this work, we described the formation of polymeric networks with potential antimicrobial character based on an acrylate oligomer, poly(mannitol sebacate) (PMS), and an enzymatically synthesized methacrylic monomer with thiazole groups (MTA). Networks with different content of MTA were prepared, and further physico-chemically characterized by microhardness, water contact angle measurements, and differential scanning calorimetry. Monomer incorporation into the networks and subsequent quaternization to provide thiazolium moieties affected the mechanical behavior and the surface wettability of the networks. Moreover, the introduction of permanent cationic charges in the network surface could give antimicrobial activity to them. Therefore, the antibacterial behavior and the hemotoxicity were analyzed against Gram-positive and Gram-negative bacteria and red blood cells, respectively.

Monomeric and Polymeric Mesoionic N-Heterocyclic Carbene-Tethered Silver Nanoparticles: Synthesis, Stability, and Catalytic Activity.

In recent years, N-heterocyclic carbenes (NHCs) have garnered significant attention as promising alternatives to thiols to stabilize metallic nanoparticles and planar surfaces. While most studies thus far have focused on NHC-functionalized gold nanoparticles (AuNPs), as an ideal platform to investigate the role of NHCs in stabilizing such nanoparticles, their ability to protect more unstable coinage metal nanoparticles, such as silver nanoparticles (AgNPs), has been largely overlooked. This is despite the fact that AgNPs possess a much more sensitive optical response that, upon their enhanced stability, can broaden their scope of application in various fields, including nanomedicine and catalysis. In this study, the synthesis and use of monomeric and polymeric mesoionic NHC-Ag(I) complexes as precursors to mono- and multidentate NHC-tethered AgNPs are reported. The polymeric analog was obtained by first synthesizing a polymer, containing 1,2,3-triazole repeat units, employing the copper-catalyzed alkyne-azide cycloaddition click polymerization of monomers containing diazide- and dialkyne functional groups. Subsequent quaternization of the triazole moieties and Ag insertion yielded the target NHC-Ag-containing polymer. Using this polymer as well as its monomeric analog as substrates, AgNPs with either catenated networks of NHCs or monomeric NHCs were fabricated by their reduction using borane-tert-butylamine complex. Our stability studies demonstrate that while monomeric NHCs impart some degree of stability to AgNPs, particularly at elevated temperatures in aqueous as well as organic medium, their polymeric analogs further enhance their stability in acidic environment (pH = 2) and against glutathione (3 mM), as an example of a biologically relevant thiol, in aqueous media. To highlight the application of these NHC-functionalized AgNPs in catalysis, we explore the aqueous phase reduction of methyl orange and 4-nitrophenol.

Coagulation-flocculation of Microcystis aeruginosa by polymer-clay based composites

Coagulation-flocculation is a critical treatment to reduce operational problems at Drinking Water Treatment Plants (DWTPs), created by episodes of cyanobacterial blooms in surface waters. There is a need for the search of good coaguflocculants that avoid release of intracellular toxins for a safer sustainable production. Clay-polymer interactions were examined for the development of efficient composites for their use as coaguflocculants for Microcystis aeruginosa (M. aeruginosa) suspensions. Polymers derived from poly-4-vinylpyridine (PVP) were quaternized on the pyridinic N by introducing methyl and hydroxyethyl moieties. These polymers were toxic per se; however, composites prepared either from their sorption or grafting on the clay surface of a montmorillonite exhibited null toxicity, The combination of infrared and X-ray diffraction data with thermal analysis showed a train conformation of the sorbed polymers on the clay surface whereas a brush conformation was elucidated for the grafted polymers. Only the composite prepared from grafting and subsequent quaternization with methyls was an efficient coaguflocculant, due to its high positive surface potential (+39 mV) which allowed a close contact between the quaternary moieties of the brushes and the negative cell wall. A patch flocculation mechanism was involved, with the riks of resuspension of the coagulated cells if the composite added in excess. The optimum ratio between the amount of coagulated cyanobacteria and this composite expressed as equivalent to polymer content was 7.2 × 107 cells/mg polymer. This ratio was determined in axenic cultures of M. aeruginosa, but was reduced 5-fold in natural surface waters due to natural organic matter (NOM) content and heterogeneity. This study has demonstrated the relevance of the type of modification of the clay mineral surface with polymers to obtain good coaguflocculants of cyanobacterial cells, that can be extended to other microorganisms.

Quaternized salicylaldehyde Schiff base side-chain polymer-grafted magnetic Fe3O4 nanoparticles for the removal and detection of Cu2+ ions in water

In this study, quaternized salicylaldehyde Schiff base side-chain polymer grafted magnetic Fe3O4 nanoparticles (Fe3O4@SiO2-PAP) were formed via the surface-initiated reversible addition-fragmentation chain-transfer polymerization of 2-(dimethylamino)ethyl methacrylate, subsequent quaternization with 5-chloromethylsalicylaldehyde and Schiff condensation with 2-aminophenol. The prepared nanohybrid was characterized by scanning and transmission electron microscopes, Fourier transform infrared spectroscopy, X-ray diffractometer, vibrating sample magnetometer and X-ray photoelectron spectroscopy. Fe3O4@SiO2-PAP was found to disperse well in water due to the strong hydrophilicity of the immobilized polymer. Cu2+ ion adsorption by the nanohybrid followed both pseudo-second-order kinetic and Langmuir isotherm models, and a maximum adsorption capacity of 59.98 mg/g was attained, with good repeatability. In addition, the nanohybrid exhibited significant and sensitive fluorescence quenching characteristics after capturing Cu2+ ions in water with good selectivity among the other studied cations. The fluorescence detection linear range was 0.1–2 mg/L, with the lowest detection limit measured as 0.125 μmol/L. Moreover, the nanohybrid exhibited high reusability for Cu2+ ion adsorption and sensing applications. Finally, the interaction of grafted Schiff base ligand with Cu2+ ions was analyzed using theoretical calculations. Consequently, the developed nanohybrid offers a new pathway for the removal and detection of Cu2+ ions in water.

Derivatization of Marine‐Derived Fascaplysin via Highly Regioselective Suzuki‐Miyaura Coupling Contributing to the Enhanced Antibacterial Activity

AbstractA new methodology for the synthesis of fascaplysin derivatives has been established. A library of diversified fascaplysins can be efficiently and quickly prepared by regioselective Suzuki‐Miyaura coupling and subsequent quaternization for the first time. The minimum inhibitory concentration assessment showed that the unique 5‐ring coplanar aromatic system plays a key role in the resulting bioactivity, and functional groups at different substitution position exert differentiable impact on the bactericidal activity. some synthesized fascaplysin derivatives exhibited higher antibacterial activities than the pristine fascaplysin and the positive controls, especially against Gram‐negative bacteria Escherichia coli (ATCC 25922). These novel fascaplysin derivatives may have promising application potentials as bactericidal drugs.

Development of recoverable adsorbents for Cr(VI) ions by grafting of a dimethylamino group-containing monomer on polyethylene substrate and subsequent quaternization

ABSTRACT A polymeric adsorbent for removal of hexavalent chromium (Cr(VI)) ions was developed by the photografting of 2-(dimethylamino)ethyl methacrylate (DMAEMA) to a polyethylene (PE) mesh and subsequent quaternization with iodoalkanes of different alkyl chain lengths. The grafting of DMAEMA and subsequent quaternization were verified by the FT-IR and XPS measurements. The Cr(VI) ion adsorption capacity of the DMAEMA-grafted PE meshes had the maximum value at the grafted amount of 2.6 mmol/g in a 0.20 mM K2Cr2O7 solution at pH 3.0 and 30°C. The adsorption behaviour obeyed the pseudo-second order kinetic model and well expressed by Langmuir isotherm. These results suggest that the Cr(VI) ion adsorption occurs through the electrostatic interaction mainly between protonated dimethylamino groups and hydrochromate (HCrO4 -) ions. The adsorption capacity of the quaternized PE-g-PDMAEMA meshes increased with an increase in the degree of quaternization and/or the alkyl chain length of the iodoalkanes used and the maximum adsorption ratio was obtained at the degree of quaternization of 54.2% for the iodoheptane-quaternized PE-g-PDMAEMA (PE-g-QC7PDMAEMA) mesh. This value was about 1.86 times higher than that of the PE-g-PDAMEMA mesh. Cr(VI) ions were successfully desorbed from the PE-g-PDMAEMA and PE-g-QC7PDMAEMA meshes in eluents such as NaOH, NaCl, and NH4Cl. In 0.50 M NaCl, 0.10 M NH4Cl, and 0.50 mM NaOH, the adsorption and desorption process was repeatedly performed without any considerable decrease and the desorption behaviour obeyed the pseudo-second order kinetic model. These results emphasise that the PE-g-PDMAEMA meshes and their quaternized products can be applied as an adsorbent for Cr(VI) ions.

Chiral Quaternary Ammoniums Derived from Dehydroabietylamine: Synthesis and Application to Alkynylation of Isatin Derivatives Catalyzed by Silver

Abietic acid and its derivatives have broadly been used in fine chemicals and are renewable resources. Its inherent chiral rigid tricyclic phenanthrene skeleton is unique. Its utilities in asymmetric catalysis remain to be explored. A series new amide-type chiral quaternary ammoniums bearing dehydroabietylamine were designed, and prepared by two convenient steps. Acylation of dehydroabietylamine with bromoacetyl chloride afforded amide holding bromoacetyl group in higher yields using triethyl amine as base. Subsequent quaternization reaction gave the desired amide-type chiral quaternary ammoniums. The new chiral quaternary ammoniums can be used as phase-transfer catalyst (PTC) for the transition metal-catalysed alkynylation of isatin derivatives.

Ester-Containing Imidazolium-Type Ionic Liquid Crystals Derived from Bio-based Fatty Alcohols

The need to take into account the life cycle of ionic liquids (ILs), from the sourcing of the raw materials involved in their synthesis to their disposal and degradation, has become paramount in the design of new IL-type molecular structures. In the case of 1-alkyl-3-methylimidazolium salts, one of the prominent IL families, there is an increasing demand for synthetic methods involving (i) substitution of the petro-based alkyl derivatives by readily available bio-sourced surrogates and (ii) functionalization of the alkyl tail with heterofunctional groups enabling the (bio)degradation of ILs after use. Herein, a straightforward and industrially viable synthesis of lipidic imidazolium salts is reported, starting from different bio-sourced fatty alcohols, including oleic, stearyl, and lauryl alcohols. This procedure is based on the acrylation of fatty alcohols, followed by the aza-Michael addition of the imidazole group onto the acrylate moiety. Subsequent quaternization, using either methyl iodide or methyl tosylate, provides a library of 1-alkylpropionate-3-methylimidazolium salts with various alkyl chain lengths (C18, C12, and C11) and incorporating different types of counteranions (iodide, tosylate, and tetrafluoroborate). These ester-containing analogues of classical 1-alkyl-3-methylimidazolium salts are all ILs, that is, with a melting point below 100 °C. In addition, most of them exhibit a liquid-crystal behavior and can be referred to as IL crystals (ILCs). The thermal stability, as well as the phase transitions of these ILs, has been investigated by thermogravimetric analysis, as well as differential scanning calorimetry, respectively, while the molecular structure into the crystalline phase and the mesophase is studied by X-ray scattering. Interestingly, ILCs featuring unsaturated alkyl tails exhibit a low melting point, close to room temperature, and the presence of the ester function is shown to provide an enhanced stabilization of the mesophase.

A simple method of simultaneously endowing paper or fluff pulp with both high softness or appropriate fluffing properties and antimicrobial properties

As the living standard improves, disposable sanitary and household paper requires not only softness or easy to fluff in a dry state, but also good antibacterial property. In this study, a series of alkyl quaternary ammonium salts (AQAS), a kinds of antibacterial-debonding agents, were synthesized by using a two-step process. The SN2 nucleophilic substitution reaction was designed between triethanolamine and sulfoxide chloride, and followed subsequent quaternization by tertiaryamines with different long alkyl chains. The obtained products can be used as an antibacterial and softening/debonding agent for improving the performance of paper or fluff pulp. The results showed that these new compounds can endow antibacterial function and high softness to paper or control appropriate burst strength to fluff pulp. These AQAS products can be not only used in daily disposable sanitary products, but also have potential applications in other products such as glass spacer paper, advanced household paper, or antibacterial tissue products to prevent microbial contamination.

Antibacterial cotton fabric prepared by surface-initiated photochemically induced atom transfer radical polymerization of 2-(dimethylamino)ethyl methacrylate with subsequent quaternization

Antibacterial highly grafted cotton fabric with good laundry resistance was prepared using photoATRP in the presence of air.

Heterocyclization of amino alcohols into saturated cyclic quaternary ammonium salts

Cyclodehydration of available N-alkylethanolamines with aldehydes and simultaneous or subsequent quaternization afford functionalized quaternary ammonium salts of N-nitroimidazolidine, oxazolidine and annulated bismorpholine type. Further replacement of their anions with residues of explosive acids provides a series of energyintensive quaternary salts with a rich hydrogen content possessing satisfactory energy characteristics and sufficiently high thermal stability.

Radiation grafting of dimethylaminoethyl methacrylate on cotton linter and subsequent quaternization as new eco-friendly adsorbent for phosphate removal.

Quaternary ammonium salt type cotton linter (QCL) was synthesized by radiation grafting of dimethylaminoethyl methacrylate (DMAEMA) onto cotton linter and subsequent quaternization. Batch and column adsorption experiments were used to evaluate the adsorption behaviors of the QCL for phosphate. The adsorption kinetics of QCL for phosphate were well obeyed pseudo-second-order mode. The adsorption isotherms were well fitted by Langmuir, Temkin, and Dubinin-Radushkevich model. Column experiments showed that the breakthrough curves were dependent on the inlet concentration and flow rate but independent on space velocity. Moreover the QCL can be effectively regenerated for further repeated use at least 10cycles. And QCL exhibited good selective adsorption for phosphate. Such high adsorption and desorption efficiency of QCL made it employing for phosphate adsorption in practical application.

Novel anion exchange membrane with low ionic resistance based on chloromethylated/quaternized‐grafted polystyrene for energy efficient electromembrane processes

ABSTRACTA novel anion‐exchange membrane has been manufactured by chloromethylation and subsequent quaternization of polystyrene within a graft copolymer films based on UV‐oxidized polymethylpentene. Particular attention is given to the kinetics of chloromethylation and the influence of the reaction conditions on the properties of the anion‐exchange membranes. By means of variation of the polystyrene content and its crosslinking degree we have obtained membranes that have an ion‐exchange capacity from 1.1 to 2.9 mmole g−1, anion transport numbers between 91.0 and 95.5% and specific ionic conductivities ( ranging from 2 to 25 mS cm−1. The developed membranes due to their low thickness and high conductivities have a remarkably low surface ionic resistance of around 0.6 Ω cm2. It was calculated that the use of the developed materials will increase the efficiency of reverse electrodialysis energy production by 8–10% compared to the state of the art membranes. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 137, 48656.

Facile Preparation of an Ether-Free Anion Exchange Membrane with Pendant Cyclic Quaternary Ammonium Groups

Ether-bond-free polyfluorene (PBF) anion exchange membranes (AEMs) containing flexible alkyl pendent chains terminated with piperidinium cations were prepared via one-pot, superacid-catalyzed polycondensation and a subsequent quaternization reaction. Hydrophilic and hydrophobic microphase segregation was observed in all AEMs. The hydroxide conductivity of PBF2-Br reaches up to 86 mS cm–1 at 80 °C, and 1H NMR showed no measurable degradation after alkaline treatment in aqueous NaOH (1 M) solution for 1200 h at 80 °C. Besides, a peak power density of 410 mW cm–2 was achieved at 60 °C for an alkaline fuel cell using the selected PBF1-OH (OH– form) as AEM.

Molecularly designed, solvent processable tetraalkylammonium-functionalized fluoropolyolefin for durable anion exchange membrane fuel cells

A new generation of solvent processable fluoropolyolefin was prepared and explored for durable anion exchange membrane fuel cells. By one-pot Ziegler-Natta copolymerization of a fluorinated monomer (1-(but-3-en-1-yl)-4-fluorobenzene) with 11-bromo-1-undecene and subsequent quaternization with trimethylamine, a series of tetraalkylammonium-functionalized fluoropolyolefin was synthesized by varying the molar ratio between monomers. The excellent solubility of the quaternized fluoropolyolefins provided by fluorinated moieties enabled the solvent processability to afford transparent and robust AEMs (PBFB-QA). Compared to heterogeneous quaternized membranes (H-PBFB-QA) and the corresponding non-fluorinated AEMs counterparts, the homogeneous quaternized PBFB-QA membrane showed lower water uptake due to the high hydrophobicity of fluorine atoms and more compact entanglement of polymer chains during solvent casting process. It was found that PBFB-QA membrane with an IEC of 1.47 meq/g showed the highest hydroxide conductivity of 29.2 mS/cm at 20 °C in spite of its low water uptake (11.9 wt%) and hydrated number (λ = 4.4). Thus, fluoropolyolefin AEMs standed out from the other reported polyolefin-based AEMs with the highest λ-normalized hydroxide conductivity, indicating the efficient ion transport in AEMs with the aid of less water. In addition to high ionic conductivity, fluoropolyolefin AEMs also exhibited excellent alkaline stability, and the retention of the conductivity of PBFB-QA-18 membrane was 89.5% after 700 h of aging in 1 M NaOH at 80 °C. More importantly, in contrast to the non-fluorinated polyolefin-based AEMs, fluoropolyolefin AEM showed better initial fuel cell device performance with a maximum power density of 133 mW/cm2 at 60 °C, and impressive device durability of alkaline fuel cell using the fluoropolyolefin AEM was observed with no loss of performance over 80 h of operation at 60 °C at a constant cell voltage of 0.3 V.

Comb‐shaped diblock copolystyrene for anion exchange membranes

ABSTRACTTo improve the properties of diblock copolystyrene‐based anion exchange membranes (AEMs), a series of AEMs with comb‐shaped quaternary ammonium (QA) architecture (QA‐PSm‐b‐PDVPPAn‐xC where x denotes the number of carbon atoms in different alkyl tail chains and has values of 1, 4, 8, and 10 and C denotes carbon) were designed and synthesized via subsequent quaternization reactions with three different alkyl halogens (methyl iodide and N‐alkane bromines (CH3[CH2] x‐1Br where x = 4, 8, and 10). Compared with triblock analogues quaternized with methyl iodide in our previous research, QA‐PSm‐b‐PDVPPAn‐xC (x = 4, 8, and 10) AEMs are more flexible with the introduction of a long alkyl tail chain; this probably impedes crystallization of the rigid polystyrene‐based main chain and induces sterically adjustable ionic association. An increase in the pendant alkyl tail chain length generally led to enhanced microphase separation of the obtained AEMs, and this was confirmed using small‐angle X‐ray scattering and atomic force microscopy. The highest conductivity (25.5 mS cm−1) was observed for QA‐PS120‐b‐PDVPPA80‐10C (IEC = 1.94 meq g–1) at 20 °C. Furthermore, the water uptake (&lt;30%) and swelling ratio (&lt;13.1%) of QA‐PSm‐b‐PDVPPAn‐xC AEMs are less than half of these corresponding values for their triblock counterparts. The QA‐PS120‐b‐PDVPPA80‐10C membrane retained a maximum stability that was as high as 86.8% of its initial conductivity after a 40‐day test (10 M NaOH, 80 °C), and this was probably because of the steric shielding of the cationic domains that were surrounded by the longest alkyl tail chains. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47370.