Sulfobetaine Groups Research Articles

SYNTHESIS OF N‐SULFOPROPYLATED HYPERBRANCHED POLYETHYLENEIMINE WITH ENHANCED BIOCOMPATIBILITY AND ANTIMICROBIAL ACTIVITY

Hyperbranched polyethyleneimine having 25,000Da molecular weight was functionalized by a simple sulfopropylation reaction, affording a novel N‐sulfopropylated PEI derivative (PEI‐SO3‐). The successful introduction of N‐sulfopropyl and sulfobetaine groups to the amino groups of PEI was spectroscopically confirmed. Furthermore, the antibacterial and anti‐cyanobacterial activity of PEI‐SO3‐ in comparison to the parent PEI were investigated on two type heterotrophic bacteria, i.e., Gram (‐) Escherichia coli and Gram (+) Staphylococcus Aureus bacteria, and one type of autotrophic cyanobacterium, i.e. Synechococcus sp. PCC 7942. Both PEI‐SO3‐ and PEI showed an enhanced, concentration‐dependent antibacterial and anti‐cyanobacterial activity against the tested bacteria strains, with PEI‐SO3‐ exhibiting higher activity than the parent PEI, signifying that the introduction of the sulfopropyl and sulfobetaine groups to the PEI amino groups enhanced the antibacterial anti‐cyanobacterial properties of PEI. In the case of cyanobacteria, PEI‐SO3‐ was found to affect the integrity of the photosynthetic system by the inhibition of Photosystem‐II electron transport activity. Cytocompatibility and hemocompatibility studies revealed that PEI‐SO3‐ exhibits high biocompatibility, suggesting that PEI‐SO3‐ could be considered as an attractive antibacterial and anti‐cyanobacterial candidate for various applications in the disinfection industry and also against the harmful cyanobacterial blooms.

Post-Modification Approach for Self-Exfoliated Synthesis of Pyridinium Sulfobetaine Covalent Organic Frameworks for Enhanced Lithium-Ion Conductivity.

While covalent organic frameworks (COFs) have been extensively investigated in the field of organic electrolyte materials, there is potential for further enhancement of their room-temperature ionic conductivity. This study introduces a novel methodology to induce self-exfoliation in the parent COF during synthesis through a postmodification technique. This process yields covalent organic nanosheets that feature pyridinium sulfobetaine groups, referred to as PS-CON. Due to the strategic arrangement of pyridinium cations and sulfobetaine anions, the charge distribution in PS-CON varies substantially, leading to a significant enhancement in lithium-ion dissociation. The methodically organized one-dimensional pore channels, along with the linear structure of the pyridinium sulfobetaine groups, facilitate the lithium-ion transport. PS-CON demonstrated a remarkable ionic conductivity of 2.19 × 10-4 S cm-1and a low activation energy (0.26 eV) coupled with a broad electrochemical stabilization window (4.05 V). Furthermore, the symmetrical cell (Li|Li@PS-CON|Li) demonstrates stable Li plating/stripping for more than 1200 h, which highlights the vast potential of pyridinium-sulfobetaine based zwitterionic nanosheets as high-performance organic electrolytes.

Enhancement of antifouling and mechanical properties of polysulfone membrane using zwitterionic biphenyl polyimide as additive

Biphenyl polyimides, which are known by its excellent heat resistance and mechanical properties, were synthesized by adjusting the molar ratio of monomers, followed by end-functionalized with zwitterionic group via reaction with 1,3-propanesultone. The zwitterionic sulfobetaine biphenyl polyimide (z-biph-PI) copolymers with different hydrophobic chain lengths were employed as the additive for the preparation of polysulfone (PSf) membrane. X-ray photoelectron spectrometry (XPS) measurement on membrane surfaces revealed that the sulfobetaine groups of z-biph-PI migrated toward water in the membrane formation process, during which a large amount of porous, narrow and densely packed pores were created as illustrated in scanning electron microscopy (SEM) images. Therefore, the incorporation of z-biph-PI simultaneously enhanced the pure water flux and protein rejection ratio of membranes, overcoming the trade-off effects between permeability and selectivity. The adsorption of bovine serum albumin decreased from ∼47.7 μg/cm2 for the pristine membrane to a minimum of ∼12.4 μg/cm2 for the blend membrane. More importantly, the tensile strength and elongation at break were also simultaneously improved due to the unique mechanical property of biph-PI and the strong π-π interaction between biphe-PI and PSf. Meanwhile, the blend membrane exhibited excellent filtration and thermal stability. All these characteristics of the blend membrane made it promising in ultrafiltration application.

Combination of ring-opening polymerization and “click” chemistry towards functionalization of polycaprolactone with sulfobetaine groups

A novel polycaprolactone (PCL) bearing sulfobetaine (SB) and N,N-dimethylamine (DMA) pendent groups distributed randomly along the biodegradable PCL backbone, P(SBCL-co-DMACL-co-CL), PSDCC was synthesized by combination of ring-opening polymerization and ‘‘click’’ chemistry. The chemical composition and the structure of PSDCC were confirmed by 1H nuclear magnetic resonance (1H NMR) spectroscopy, fourier transform infrared (FT-IR) spectroscopy and gel permeation chromatography (GPC). Studies on the self-assembly in water show that the PSDCC nanoparticles have a narrow size distribution with the diameter about 140 nm. Besides, the nanoparticles possess enhanced stability, pH-sensitive doxorubicin (DOX) release behavior, excellent biocompatibility and cellular uptake to MCF-7 cells. Therefore, the copolymer of PSDCC synthesized by this simple method is a highly promising material as a new drug delivery carrier for cancer therapy.

Synthesis of silica bearing sulfobetaine and sulfonic groups and their electrorheological response

Organically modified silica bearing amino groups (SiO2-NH2) was prepared by the simple sol-gel procedure followed by treatment with butanesultone to produce zwitterionic silica bearing sulfobetaine groups (SiO2-SB). This particle was then treated with sulfuric acid to prepared particles carrying both sulfonic acid and ammonium salt (SiO2-SO3H). These particles were characterized by different methods and dispersed in silicone oil (15 wt%) to evaluate the electrorheological (ER) performance. Thermogravimetric (TG) analysis, zeta potential and Fourier transform infrared (FTIR) spectroscopy confirmed the structure of the modified silica. The ER response was evaluated using controlled shear stress (CSR) and oscillatory mode. The SiO2-NH2 and SiO2-SB based fluids displayed the highest shear stress at low shear rate even without an applied electric field. However the higher ER efficiency and lower leakage current was observed for the fluid containing SiO2-SO3H. From dielectric analysis, it was demonstrated that the zwitterionic SiO2-SB particle provided faster relaxation time and larger permittivity difference. Thus, it is possible to conclude that the lower viscosity of the SiO2-SO3H based fluid without electric field also plays an important role for a good ER efficiency. Both SiO2-SB and SiO2-SO3H particles are suitable for producing ER fluids due to their better dielectric properties and relaxation time. The former also presented better sedimentation stability.

Improving the Mechanical Properties and Tribological Behavior of Sulfobetaine Polyurethane Based on Hydrophobic Chains to Be Applied as Artificial Meniscus.

In the context of meniscus reconstruction in knee joints, current bulk biomaterials fail to meet the clinical demands for both excellent mechanical strength and low coefficient of friction. In this research, zwitterionic polyurethanes (PUs) with varying sulfobetaine (SB) groups were synthesized as the potential materials for artificial meniscus to investigate the relationship between the structures of SB groups and the performances of PUs. Under the saturation condition of 3 mg/mL hyaluronic acid aqueous solution, PU with long-alkyl chains and SB groups (PU-hSB4) exhibited a good tensile modulus (111.5 MPa) because the hydrophobic interaction of carbon chains was able to maintain the ordered aggregations of hard segment domains. Interestingly, hydrophobic chains in the molecular chain could also improve the tribological performance of PU-hSB4 instead of resulting from the surface roughness of samples, the components of lubricants, and the counterface of samples. A thicker and relatively stable hydration layer of noncrystal water was formed on the surface of PU-hSB4, which exhibited superior resistance to external forces compared to other PUs. Even if the hydration layer was damaged, PU-hSB4 was able to resist the compression of cartilage due to its high surface modulus, thus maintaining a similar and stable coefficient of friction (0.15-0.16) to native meniscus (0.18) and excellent wear resistance. In addition, the low cytotoxicity of PU-hSB4 further demonstrated its great potential to be applied in artificial meniscus instead.

Engineering a novel zwitterionic polyurethane nanofiltration membrane with enhanced fouling resistance for water reclamation

Design of zwitterionic polymers with feasible methods is rational for grafting membrane surface and enhancing its antifouling property. Herein, we propose a facile and scalable “one-pot” polymerization approach to synthesize a novel thiolated zwitterionic polyurethane (TZP) and graft it onto a polydopamine activated membrane surface via Michael addition for engineering antifouling nanofiltration (NF) membranes. The chemical structure of TZP was confirmed by the 1H nuclear magnetic resonance and it had a weight average molecular weight of 13,000 g mol−1. The Fourier transform infrared and X-ray photoelectron spectra confirm the successful introduction of sulfobetaine groups on membrane surfaces. The TZP grafting neutralized the negative charge of PDA interlayer and further improved membrane hydrophilicity. The pore size and ion selectivity of the NF membranes were optimized by tuning TZP concentrations. Satisfactory divalent anion retention along with a molecular weight cut-off of ∼800 Da was achieved at 30 g L−1 TZP concentration (i.e., TZP-30). During two cycles of synthetic wastewater filtration, the TZP-30 membrane exhibited excellent fouling resistance and satisfactory flux recovery rate compared with a benchmark commercial NF membrane. Our findings shed light on the future design of novel zwitterionic polymers and antifouling NF membranes for sustainable water reclamation.

Ion-Specific Antipolyelectrolyte Effect on the Swelling Behavior of Polyzwitterionic Layers

In this study, we systematically investigate the interactions between mobile ions generated from added salts and immobile charges within a sulfobetaine-based polyzwitterionic film in the presence of five salts (KCl, KBr, KSCN, LiCl, and CsCl). The sulfobetaine groups contain quaternary alkylammonium and sulfonate groups, giving the positive and negative charges. The swelling of the zwitterionic film in the presence of different salts is compared with the swelling behavior of a polycationic or polyanionic film containing the same charged groups. For such a comparative study, we design cross-linked terpolymer films with similar thicknesses, cross-link densities, and charge fractions, but with varying charged moieties. While the addition of salt in general leads to a collapse of both cationic and anionic films, the presence of specific types of mobile anions (Cl-, Br-, and SCN-) considerably influences the swelling behavior of polycationic films. We attribute this observation to a different degree of ion-pair formations between the different types of anionic counterions and the immobile cationic quaternary alkylammonium groups in the films where highly polarizable counterions such as SCN- lead to a high degree of ion pairing and less polarizable counterions, such as Cl-, cause a low degree of ion pairing. Conversely, we do not observe any substantial effect of varying the type of cationic counterions (K+, Li+, and Cs+), which we assign to the lack of ion pairing between the weakly polarizable cations and the immobile anionic sulfonate groups in the films. In addition, we observe that the zwitterionic films swell with increasing ionic strength and the degree of swelling is anion dependent, which is in agreement with previous reports on the "antipolyelectrolyte effect". Herein, we explain this ion-specific swelling behavior with the different cation and anion abilities to form ion pairs with quaternary alkylammonium and sulfonate in the sulfobetaine groups.

Fibrin formation and fractal organization at cationic, anionic, and zwitterionic polymer coated interfaces.

Biomaterial-associated thrombosis remains a persistent challenge whenever medical devices are inserted in blood vessels. The issue is principally addressed by the development of antithrombogenic coatings that prevent the formation of blood clots, e.g. by limiting adsorption of fibrin - the core protein network of a clot. Charged polymers (i.e. polyelectrolytes and zwitterionic polymers) show potential as coating materials for medical devices, and we here investigate these polymer coatings in the context of biomaterial-associated thrombosis. Our findings indicate that fibrin polymerization can yield a surface-dependent distribution of fractal-like branched structures and amorphous aggregates, with surface-induced fibrin formation dominating for anionic polymer interfaces and recruitment of bulk-formed fibrin dominating for cationic polymer interfaces. In addition, we identify coatings containing zwitterionic sulfobetaine groups as promising candidates for antithrombogenic biomaterials.

Synergistic hydration lubrication of polyurethane meniscus based on zwitterionic structures and hyaluronic acid

In this study, polyurethanes with graded sulfobetaine content (PU-SBs) were employed to resolve the high friction of artificial menisci. Under the simulated gait of knee joints, the coefficient of friction of PU-SB60 in hyaluronic acid (HA) aqueous solution was similar to that of the native meniscus. Importantly, this phenomenon was caused by synergistic hydration lubrication based on sulfobetaine groups and HA, that a thicker and stronger hydration layer was preferred to form quickly on the surfaces of HA-adsorbed PU-SB60 and was harder to be destroyed by the friction force. Furthermore, PU-SB60 exhibited both excellent modulus and long-term low cytotoxicity. Therefore, PU-SB60 has the potential to be applied for artificial menisci due to its overall performance.

Preparation of antifouling ultrafiltration membranes from copolymers of polysulfone and zwitterionic poly(arylene ether sulfone)s

The past few decades have witnessed rapid gains in our demands of antifouling membranes such as water purification membranes and hemodialysis membranes. A variety of methodologies have been proposed for improving the antifouling performance and the hemocompatibility of the membranes. In this study, a series of copolymers (PSF-PESSB) containing polysulfone (PSF) and poly(arylene ether sulfone) bearing pendant zwitterionic sulfobetaine groups (PESSB) were prepared via one-pot polycondensation. Subsequently, the ultrafiltration (UF) membranes were prepared from different zwitterion-containing copolymers. The prepared membranes showed high thermal stability and mechanical properties. Besides, it also displayed attractive antifouling performance and blood compatibility. Compared with the original PSF membrane, the amount of protein absorption on the modified membrane was reduced; the flux recovery ratio and the resistance to blood cells were significantly improved. The results of this work suggest that PSF-PESSB membranes are expected to be applied in blood purification. The introduction of zwitterion-containing polymers to membranes paves ways for developing advanced hemodialysis technologies for crucial process.

A versatile method for multiclass determination of β-lactam drugs in urine by solid-phase extraction followed by HILIC-UV

A method for multiclass determination of β-lactam antibiotics in human urine by solid-phase extraction (SPE) prior to quantification by hydrophilic interaction liquid chromatography (HILIC) was developed. Four cephalosporins, one carbapenem and four penicillins were selected among the most prescribed β-lactam drugs. A HILIC column – silica-linked zwitterionic sulfobetaine groups – proved to be valuable for analysis of these three classes of highly hydrophilic compounds, with suitable capacity factors, peak shape and resolution gained by proper selection of the chromatographic conditions. Sample extraction has been performed on Strata™-X. The quick SPE procedure entirely developed in urine successfully combined sample clean-up, avoiding protein precipitation before extraction, with recovery higher than 66% (interday RSD < 15%, n = 5), and method quantification limits in urine in the range 1–4 µg mL−1. Selectivity has been proven on blank urine samples, also in presence of several non-target pharmaceuticals, and the method was applied to the analysis of samples from four patients under β-lactams therapy.

Application of a hybrid zwitterionic hydrophilic interaction liquid chromatography column in metabolic profiling studies

Metabolic phenotyping studies using mouse liver extracts as a model, performed on a novel zwitterionic HILIC UHPLC column, which is based on ethylene-bridged hybrid organic/inorganic particles bonded with sulfobetaine groups and packed into column hardware modified with hybrid surface technology are reported. Initially the chromatographic performance was evaluated under different mobile phase conditions using selected metabolite standards. Following optimization of the chromatographic conditions for 88 hydrophilic metabolites both targeted and untargeted profiling analyses were performed on tissue extracts using LC-MS/MS and LC-TOF/MS, respectively.Chromatographic efficiency parameters such as peak resolution, peak shapes, selectivity and precision in retention and peak areas as well as characteristics that are critical for metabolic profiling analysis such as metabolite coverage and retention time distribution were assessed.The hybrid zwitterionic column exhibited efficient chromatographic separations providing analysis of ca 80 hydrophilic metabolites from different chemical classes and polarities. Utilizing a one-dimensional separation both targeted and untargeted profiling provided comprehensive metabolic signatures that enabled the acquisition of the metabolic phenotypes of the tissue extracts.

A Zwitterionic Polyurethane Nanoporous Device with Low Foreign‐Body Response for Islet Encapsulation

Encapsulation of insulin-producing cells is a promising strategy for treatment of type 1 diabetes. However, engineering an encapsulation device that is both safe (i.e., no cell escape and no breakage) and functional (i.e., low foreign-body response (FBR) and high mass transfer) remains a challenge. Here, a family of zwitterionic polyurethanes (ZPU) with sulfobetaine groups in the polymer backbone is developed, which are fabricated into encapsulation devices with tunable nanoporous structures via electrospinning. The ZPU encapsulation device is hydrophilic and fouling-resistant, exhibits robust mechanical properties, and prevents cell escape while still allowing efficient mass transfer. The ZPU device also induces a much lower FBR or cellular overgrowth upon intraperitoneal implantation in C57BL/6 mice for up to 6 months compared to devices made of similar polyurethane without the zwitterionic modification. The therapeutic potential of the ZPU device is shown for islet encapsulation and diabetes correction in mice for ≈3 months is demonstrated. As a proof of concept, the scalability and retrievability of the ZPU device in pigs and dogs are further demonstrated. Collectively, these attributes make ZPU devices attractive candidates for cell encapsulation therapies.

The strategy of modulation blood responses by surface modification with different functional groups on polyester film.

A main problem in the design of blood-contacting biomaterials has been the deficiency of a systematic understanding of blood-biomaterial interactions and the strategy to modulate blood responses. In this work, different functional groups including carboxyl (COOH), hydroxyl (OH) and zwitterionic sulfobetaine group (⊕N((CH3 )2 )(CH2 )3 SO3-○- , SMDB) were grafted on the poly (butylene terephthalate) (PBT) film to study how the functional groups modulate blood responses and in terms of interaction with the coagulation system, the complement system, and platelets. The results showed protein absorption and platelet adhesion was stronger on the PBT bearing COOH group than PBT films bearing OH and zwitterionic sulfobetaine groups (total protein (μg/cm2 ): 32.92 ± 5.89 vs. 22.02 ± 1.44 vs. 19.09 ± 1.59; platelet adhesion (/mm2 ): 1,626.7 ± 120.1 vs. 1,395.6 ± 363.3 vs. 1,102.2 ± 373.7), which had a rougher and negatively charged surface, and the coagulation system was inhibited by binding fibrinogen (Fg) and coagulation factors. Meanwhile, PBT-PSMDB showed anticoagulant property and induced platelet activation. As a result, complement formation on these two films were less than PBT bearing OH groups by inhibiting the coagulation system (C3a (ng/ml): 3,745.4 ± 143.9 vs. 3,290.9 ± 249.7 vs. 4,887.9 ± 88.9; C5a (ng/ml): 22.1 ± 2.6 vs. 22.3 ± 1.8 vs. 27.9 ± 2.0). On the other hand, PBT bearing OH groups did not facilitate remarkable platelet adhesion and activation, and had no influence on platelet aggregation, hypotonic shock response, and coagulation system. The above results showed that the blood responses were highly interlinked, and could be modulated by grafting with different functional groups on the biomaterial surfaces. These findings may help identify a strategy to design materials with better hemocompatibility for blood contact, filtration, and purification applications.

Application of hydrophilic interaction liquid chromatography coupled with tandem mass spectrometry for the retention and sensitivity studies of antisense oligonucleotides

The aim of the present investigation was application of hydrophilic interaction liquid chromatography as an alternative chromatographic approach for the study of antisense oligonucleotides. The influence of several mobile phases, differing with the salt type, their concentration and pH value on the retention and the separation of antisense oligonucleotides has been examined for this purpose. Four different stationary phases were also applied including unmodified silica, silica modified with the use of sulfobetaine groups, polyhydroxy and aminopropyl groups. Such wide range of tested conditions has been useful in better understanding of the retention mechanism of tested compounds. The results obtained during this investigation indicated that greater retention, greater peaks symmetry, as well as more effective separation of oligonucleotides, were obtained for the zwitterionic stationary phase. Moreover, the optimization of tandem mass spectrometry parameters with the use of Central Composite Design was performed and different mobile phases were tested to choose that one, which provided the greatest antisense oligonucleotides peak areas in Multiple Reaction Monitoring mode and consequently, the greatest possible sensitivity. Hydrophilic interaction liquid chromatography was compared with the ion pair chromatography, commonly used in the analysis of oligonucleotides. Both techniques were compared in terms of selectivity of separation as well as the sensitivity of their determination. Obtained results proved that ion pair chromatography provided better results in terms of separation efficiency and peak areas in Multiple Reaction Monitoring for tested conditions. However, these results do not preclude application of hydrophilic interaction liquid chromatography as an alternative chromatographic approach for the oligonucleotides analysis especially when a mobile phase without ion pair reagents is required.

Synthesis of a poly(sulfobetaine-co-polyhedral oligomeric silsesquioxane) hybrid monolith via an in-situ ring opening quaternization for use in hydrophilic interaction capillary liquid chromatography.

An in-situ approach is described for synthesis of poly(sulfobetaine-co-polyhedral oligomeric silsesquioxane) [poly(sulfobetaine-co-POSS)] that can be used in a hybrid monolithic column as a hydrophilic liquid chromatography (HILIC) stationary phase. Synthesis involves (a) radical polymerization of octa(propyl methacrylate)-polyhedral oligomeric silsesquioxane (MA-POSS) and organic monomers such as dimethylaminopropyl methacrylate or vinyl imidazole, and (b) in-situ ring-opening quaternization between 1,4-butane sultone and the organic monomers. The sulfobetaine groups are generated in-situ monolith. This obviates the need for synthesis of sulfobetaine monomer previously. The pore size and permeability of the material can be tuned by using a binary porogenic system (polyethyleneglycol 600 and acetonitrile) and via the composition of the polymerization mixture. The optimized hybrid monolith owns its merits to the presence of POSS and sulfobetaine groups with good mechanical stability, the lack of residual silanol groups, and adequate hydrophilicity. The column filled with the monoliths was evaluated as a stationary phase for HILIC. Several kinds of polar compounds (including nucleosides, bases, phenols, aromatic acids and amides) were separated by using mobile phases with high organic solvent fractions in capillary liquid chromatography. Graphical abstractAn in-situ approach is described for synthesis of poly(sulfobetaine-co-polyhedral oligomeric silsesquioxane) hybrid monolithic column for use in hydrophilic liquid chromatography. The optimized monolith owns good mechanical stability, the lack of residual silanol groups and adequate hydrophilicity. Baseline separation of several kinds of polar compounds is achieved on the column. MA-POSS: octa(propyl-methacrylate) polyhedral oligomeric silsesquioxane; DMAEMA: dimethylaminoethyl methacrylate; AIBN: azodiisobutyronitrile. Poly(DMABS-co-POSS): poly(N-(4-sulfobutyl)-N-methacryloxypropyl- N,N-dimethylammonium-betaine-co-polyhedral oligomeric silsesquioxane).

Contact Line Pinning Is Not Required for Nanobubble Stability on Copolymer Brushes.

Whereas nanobubble stability on solid surfaces is thought to be based on local surface structure, in this work, we show that nanobubble stability on polymer brushes does not appear to require contact-line pinning. Glass surfaces were functionalized with copolymer brushes containing mixtures of hydrophobic and hydrophilic segments, exhibiting water contact angles ranging from 10 to 75°. On unmodified glass, dissolution and redeposition of nanobubbles resulted in reformation in mostly the same locations, consistent with the contact line pinning hypothesis. However, on polymer brushes, the nucleation sites were random, and nanobubbles formed in new locations upon redeposition. Moreover, the presence of stable nanobubbles was correlated with global surface wettability, as opposed to local structure, when the surface exceeded a critical water contact angle of 50 or 60° for polymers containing carboxyl or sulfobetaine groups, respectively, as hydrophilic side chains. The critical contact angles were insensitive to the identity of the hydrophobic segments.

Functionalization in copolymers based on 4VP:DVB for the removal of Cr(VI) ions from aqueous solution

ABSTRACTAdsorption capacity for Cr(VI) ions has been evaluated on two ion‐exchange resins. A gel‐type precursor resin was obtained by suspension polymerization of 4‐vinylpyridine and divinylbenzene monomers with 40% crosslinking degree. It was quaternized with different functional groups to give two ion‐exchange resins. The R2 resin contained sulfobetaine groups, and R3 methyl groups. The resins were characterized by Fourier transform infrared and solid‐state 13C CP/MAS NMR spectroscopy and by elemental analysis. An adsorption experiment was carried out by a batch equilibrium procedure. Langmuir and Freundlich isotherm models were used to determine the adsorption capacity. R2 and R3 resins exhibited maximum adsorption capacity qmax = 75.8 and 56.2 mg/g, respectively. The resins achieve equilibrium in 60 min. The R3 and R2 resins showed a retention capacity of 95% and 80% for the Cr(VI) ions, respectively. The behaviors of both resins were explained well by a pseudo‐second‐order kinetics model. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45548.

Design of a Zwitterion Polymer Electrolyte Based on Poly[poly (ethylene glycol) methacrylate]: The Effect of Sulfobetaine Group on Thermal Properties and Ionic Conduction

Polymer electrolytes are expected to play an overriding role in the development of sustainable lithium ion batteries. In this study, amorphous poly(poly(ethylene glycol) methacrylate) (pPEGMA) and pPEGMA functionalized with sulfobetaine pendants (pMPS8) are synthesized, and subsequently formulated with LiPF6 to be assessed as solid polymer electrolytes (SPE). The polymer properties are investigated using Differential scanning calorimetry (DSC), X‐ray diffraction (XRD), Attenuated total reflection Fourier transform infrared (FTIR) and Electrochemical Impedance Spectroscopy (EIS). These experimental analyses are used to account for the effects of a methacrylate‐type polymer as an alternative to improve Li+ mobility across the polymer, and synergic benefits of its functionalization with sulfobetaine groups. pPEGMA displayed a Tg around −49 °C, which increases in the presence of the lithium salt to −38 °C due to the interactions arising between Li+ ions and the polymer, as confirmed by XRD and FTIR characterizations. The ionic conductivity of the pPEGMA/LiPF6 system is 6.92 × 10−6 S cm−1, which denotes a partial dissociation of LiPF6 as a result of the formation of ion pairs, detected by the structural characterization. The functionalization of pPEGMA is an efficient method to decrease the Tg down to −53 °C, suggesting that pMPS8 keeps amorphous pPEGMA matrix allowing mobility of polymer chains by the presence of the sulfobetaine pendants. Evidence of this behavior is determined with the chemical and structural evaluations, and clearly observed in the increase of ionic conductivity by two orders of magnitude. Although the Tg of the pMPS8/LiPF6 system considerably augments to −24 °C, its effects are negligible in ionic conductivity (3.22 × 10−5 S cm−1), indicating that a relatively low stiff backbone arises in pMPS8 structures, which is not influenced by the presence of LiPF6 due to the strong charge delocalization generated by the sulfobetaine groups.