Sodium Salt Of Poly Research Articles

Sodium‐Ion‐Conducting Hydrogel Material: Synthesis, Characterization and Conductivity Studies

AbstractHerein we have reported single sodium ion conducting pseudo solid polymer electrolyte material, was synthesized successfully using sodium; 3,4,5,6‐tetrahydroxyoxane‐2‐carboxylate (ALG) and sodium salt of poly (acrylic Acid): SPA in the water as solvent via solution cast technique. This pseudo‐solid polymer material allows Na+ cation transport inside the matrix. The FTIR technique confirmed the appreciable interaction between the sodium alginate and sodium polyacrylate polymer. This amorphous polymer material has good flexibility, tensile strength, and good elasticity which provides a better electrode‐electrolyte interface. The material shows electrical conductivity in the range of 10−5 S/cm at room temperature and 10−4 S/cm at higher temperatures (>40 °C). The material shows electrochemical stability of 2.26 V owing to a very good amount of current density with ≈97 % ionic transport number for the sodium ion. The material shows drift ionic velocity in the range of 10−4 m/s and ionic mobility in the order of 10−6 m2/Vs at room temperature. It shows the matrix ionic diffusivity constant in the order of 10−7 m2/s. It possesses low activation energy for ionic movement inside the matrix of 0.465 eV. The matrix shows the correlated type of hopping. An appreciable amount of capacitance is associated with the matrix with minute electrode contribution.

Insight into the performance of valve-regulated lead-acid battery using sodium salt of poly(4-styrene sulfonic acid-co-maleic acid)-poly(vinyl alcohol) gel electrolyte

Insight into the performance of valve-regulated lead-acid battery using sodium salt of poly(4-styrene sulfonic acid-co-maleic acid)-poly(vinyl alcohol) gel electrolyte

In Silico Characterization of the Interaction between the PBP2a "Decoy" Protein of Resistant Staphylococcus aureus and the Monomeric Units of Eudragit E-100 and Poly(Maleic Acid-alt-Octadecene) Polymers.

Antimicrobial treatment alternatives for methicillin-resistant Staphylococcus aureus (MRSA) are increasingly limited. MRSA strains are resistant to methicillin due to the formation of β-lactamase enzymes, as well as the acquisition of the mecA gene, which encodes the penicillin-binding protein (PBP2a) that reduces the affinity for β-lactam drugs. Previous studies have shown that the use of ampicillin-loaded nanoparticles can improve antimicrobial activity on resistant S. aureus strains. However, the biological mechanism of this effect has not yet been properly elucidated. Therefore, this short communication focused on characterizing the in silico interactions of the PBP2a membrane receptor protein from S. aureus against the monomeric units of two polymeric materials previously used in the development of different nanoparticles loaded with ampicillin. Such polymers correspond to Eudragit E-100 chloride (EuCl) and the sodium salt of poly(maleic acid-alt-octadecene) (PAM-18Na). For this, molecular coupling studies were carried out in the active site of the PBP2a protein with the monomeric units of both polymers in neutral and ionized form, as well as with ampicillin antibiotic (model β-lactam drug). The results showed that ampicillin, as well as the monomeric units of EuCl and PAM18Na, described a slight binding free energy to the PBPa2 protein. In addition, it was found that the amino acids of the active site of the PBPa2 protein have interactions of different types and intensities, suggesting, in turn, different forms of protein–substrate coupling.

Synthesis of a New Polyanion Possessing Dense 1,2,3-Triazole Backbone.

Polyanions are an important class of water-soluble polymers because polyanions are utilized in a wide range of industrial fields. It is thus a great challenge to develop polyanions with novel structures to make their applications broader. In this study, a new polyanion with a dense 1,2,3-triazole backbone, poly(4-azido-5-hexanoic acid) (poly(AH)), was synthesized by copper(I)-catalyzed azide–alkyne cycloaddition (CuAAC) polymerization of t-butyl 4-azido-5-hexanoate followed by hydrolysis of the t-butyl ester groups. Turbidimetric and potentiometric titration data indicated that poly(AH) was well soluble in water under basic conditions (pH < 7) and a weaker polyanion (apparent pKa = 5.4) than polyacrylic acid (apparent pKa = 4.5). Adsorption tests exhibited that sodium salt of poly(AH) (poly(AH)Na) adsorbed most preferably Fe3+ among the four metal ions examined, i.e., Cu2+, Pb2+, Li+, and Fe3+. 1H spin-lattice relaxation time measurements indicated that Fe3+ ions were adsorbed favorably onto the 1,2,3-triazole residues.

Peptide-Based Polyelectrolyte Promotes Directional and Long Neurite Outgrowth.

Neural tissue engineering has emerged as a promising technology to cure neural damages. Although various synthetic polymers with good biocompatibility and biodegradability have been adopted as candidate materials for scaffolds, most of them require the incorporation of biomolecules or conductive materials to promote the growth of long axons. Herein we demonstrate for the first time a unique peptide-based polyelectrolyte that is ionically conductive and contains a neurotransmitter, glutamic acid. The designed polymer, sodium salt of poly(γ-benzyl-l-glutamate)-r-poly(l-glutamic acid) (PBGA20-Na), was synthesized and fabricated into a 3D fibrous scaffold with aligned fibers. Neuron-like rat pheochromocytoma (PC12) cells were cultured on the scaffolds to evaluate cell proliferation and differentiation with or without electrical stimulation. The results show that with both electrical and biochemical cues presented in the polyelectrolyte, PBGA20-Na promotes longer neurite outgrowth compared with the neutral poly(γ-benzyl-l-glutamate) (PBG) and the poly(γ-benzyl-l-glutamate)-r-poly(l-glutamic acid) (PBGA20). Furthermore, the neurite length of the cells cultured on PBGA20-Na is more than twice as long compared with the conventional biopolymer, polycaprolactone. In conclusion, PBGA20-Na is a promising biomaterial for neural tissue engineering and drug-screening platforms.

Effect of the Surface Hydrophobicity Degree on the In Vitro Release of Polar and Non-Polar Drugs from Polyelectrolyte Matrix Tablets.

This work is the continuation of a series of studies focused on establishing the relationship between the surface thermodynamic properties of polyelectrolyte matrix tablets and drug release mechanisms. In this case, two model drugs with different polarity features, such as carbamazepine (non-polar) and metoprolol succinate (polar) were used in combination with polymeric material hydroxypropyl-methyl cellulose (HPMC) and two polyelectrolytes derived from maleic anhydride corresponding to the sodium salts of poly(maleic acid-alt-ethylene) and poly(maleic acid-alt-octadecene) named PAM-0Na and PAM-18Na, respectively. The polymers were obtained and characterized as reported previously. Surface studies were performed by the sessile drop method, whilst the surface free energy was determined through Owens, Wendt, Rable and Kaeble (OWRK) semi-empirical model. By contrast, the drug release studies were performed by in vitro dissolution tests, where data were analyzed through dissolution efficiency. The results showed that, depending on the drug polarity, type and polymer proportion, surface properties and drug release processes are significantly affected.

Application of Nanoparticle Technology to Reduce the Anti-Microbial Resistance through β-Lactam Antibiotic-Polymer Inclusion Nano-Complex.

Biocompatible polymeric materials with potential to form functional structures in association with different therapeutic molecules have a high potential for biological, medical and pharmaceutical applications. Therefore, the capability of the inclusion of nano-Complex formed between the sodium salt of poly(maleic acid-alt-octadecene) and a β-lactam drug (ampicillin trihydrate) to avoid the chemical and enzymatic degradation and enhance the biological activity were evaluated. PAM-18Na was produced and characterized, as reported previously. The formation of polymeric hydrophobic aggregates in aqueous solution was determined, using pyrene as a fluorescent probe. Furthermore, the formation of polymer-drug nano-complexes was characterized by Differential Scanning Calorimetry-DSC, viscometric, ultrafiltration/centrifugation assays, zeta potential and size measurements were determined by dynamic light scattering-DLS. The PAM-18Na capacity to avoid the chemical degradation was studied through stress stability tests. The enzymatic degradation was evaluated from a pure β-lactamase, while the biological degradation was determined by different β-lactamase producing Staphylococcus aureus strains. When ampicillin was associated with PAM-18Na, the half-life time in acidic conditions increased, whereas both the enzymatic degradation and the minimum inhibitory concentration decreased to a 90 and 75%, respectively. These results suggest a promissory capability of this polymer to protect the β-lactam drugs against chemical, enzymatic and biological degradation.

Porous organic polymer/RGO composite as high performance cathode for half and full sodium ion batteries

Abstract Redox-active organic polymers are promising cathode electrodes owing to the advantages of open and flexible frame-works, renewability and environmental friendliness. Sodium salt of poly (2, 5-dihydroxy-p-benzoquinonyl sulfide)/RGO (Na2PDHBQS/RGO) composite has been fabricated via a convenient route and applied as a high performance and stable cathode for sodium ion batteries. The Na2PDHBQS/RGO was investigated in ether-based electrolyte, which demonstrated better electrochemical performances (228, 214, 203, 193, 172 and 147 mAh g−1 at 0.1, 0.2, 0.4, 0.8, 2 and 4C, respectively) than that in traditional ester-based ones. The high specific capacity, excellent cycle stability and reversibility of Na2PDHBQS/RGO may be attributed to the special porous structure, enhanced electronic conductivity by the introduction of RGO and fast sodium ion and electron diffusion rate in ether-based electrolyte. In addition, the Na2PDHBQS/RGO cathode has been assembled with disodium terephthalate (Na2TP) anode to compose a full cell for the first time, which presents an initial reversible capacity of 210 mAh g−1 at 0.1C.

Relationship between Surface Properties and In Vitro Drug Release from Compressed Matrix Containing Polymeric Materials with Different Hydrophobicity Degrees.

This work is the continuation of a study focused on establishing relations between surface thermodynamic properties and in vitro release mechanisms using a model drug (ampicillin trihydrate), besides analyzing the granulometric properties of new polymeric materials and thus establishing the potential to be used in the pharmaceutical field as modified delivery excipients. To do this, we used copolymeric materials derived from maleic anhydride with decreasing polarity corresponding to poly(isobutylene-alt-maleic acid) (hydrophilic), sodium salt of poly(maleic acid-alt-octadecene) (amphiphilic), poly(maleic anhydride-alt-octadecene) (hydrophobic) and the reference polymer hydroxyl-propyl-methyl-cellulose (HPMC). Each material alone and in blends underwent spectroscopic characterization by FTIR, thermal characterization by DSC and granulometric characterization using flow and compaction tests. Each tablet was prepared at different polymer ratios of 0%, 10%, 20%, 30% and 40%, and the surface properties were determined, including the roughness by micro-visualization, contact angle and water absorption rate by the sessile drop method and obtaining Wadh and surface free energy (SFE) using the semi-empirical models of Young–Dupré and Owens-Wendt-Rabel-Käelbe (OWRK), respectively. Dissolution profiles were determined simulating physiological conditions in vitro, where the kinetic models of order-zero, order-one, Higuchi and Korsmeyer–Peppas were evaluated. The results showed a strong relationship between the proportion and nature of the polymer to the surface thermodynamic properties and kinetic release mechanism.

Kinetics of deposition and stability of pyrocatechol –FeIII coordinated films

Metal coordination between polyphenols and metal cations like Fe3+ allows to produce conformal homogeneous and robust coatings on a vast variety of materials. The deposition kinetics and the stability of the obtained films are however only poorly investigated. In the present article it is shown that rough, granular but pinhole free coatings up to 50nm in thickness can be obtained in a one pot manner using pyrocatechol (Pyr)/Fe3+ mixtures at different stoichiometries (with Fe3+/Pyr ratios equal to 0.55 or 1.10) provided the deposition time is extended up to 24h. More importantly, we show that these films are dissolved upon oxidation of Pyr in cyclic voltammetry experiments. When the films deposited during short durations are rinsed with buffer and subsequently re-exposed to Pyr containing solution, they undergo partial dissolution most probably through a ligand exchange process. Such a dissolution process does not occur anymore in the same conditions, when the deposition time is increased above 5h. All Pyr-Fe3+ based films can be stabilized by a post-deposition of a polyelectrolyte multilayer film based on the alternated adsorption of poly(allylamine hydrochloride) and the sodium salt of poly(styrene sulfonate). The deposition of 5 bilayers of these polyelectrolytes allows suppressing the dissolution of Pyr-Fe3+ based films produced for short deposition times

The Effect of Biomaterials Used for Tissue Regeneration Purposes on Polarization of Macrophages.

Activation of macrophages is critical in the acute phase of wound healing after implantation of surgical biomaterials. To understand the response of macrophages, they are often cultured in vitro on biomaterials. Since a wide range of biomaterials is currently used in the clinics, we undertook a systematic review of the macrophage polarization in response to these different surgical biomaterials in vitro. Beside the chemistry, material characteristics such as dimension, pore size, and surface topography are of great influence on the response of macrophages. The macrophage response also appears to depend on the differences in sterilization techniques that induce lasting biochemical changes or residues of chemicals and their byproducts used for sterilization. Regarding tissue-based biomaterials, macrophages on human or porcine dermis, strongly cross-linked by chemicals elicit in general a proinflammatory response with higher amounts of proinflammatory cytokines. Synthetic biomaterials such as polyethylene, polyethylene terephthalate (PET) + polyacrylamide (PAAm), PET + sodium salt of poly(acrylic acid) (PAANa), perfluoropolyether (PFPE) with large posts, PEG-g-PA, and polydioxanone (PDO) always appear to elicit an anti-inflammatory response in macrophages, irrespective of origin of the macrophages, for example, buffy coats or full blood. In conclusion, in general in vitro models contribute to evaluate the foreign body reaction on surgical biomaterials. Although it is difficult to simulate complexity of host response elicited by biomaterials, after their surgical implantation, an in vitro model gives indications of the initial foreign body response and allows the comparison of this response between biomaterials.

Comment on "Formation of polyelectrolyte multilayers: ionic strengths and growth regimes" by K. Tang and A. M. Besseling, Soft Matter, 2016, 12, 1032.

Tang and Besseling recently published a study on the growth of polyelectrolyte multilayers formed by poly(diallyl-dimethylammonium chloride), PDADMAC, and the sodium salt of poly(4-styrenesulfonate), PSSNa. They described the different growth regimes appearing in the (PDADMAC + PSS)n multilayers within a scenario in which the appearance of interdiffusion of the polyelectrolyte chains within the multilayer architecture plays a central role in the transition between the different regimes. However, this account contrasts, without an apparent explanation, with previous experimental evidence reported in the literature.

Colloid solution of surfactant monomers and polyelectrolyte: Polymerization and properties of the resulting interpolyelectrolyte complexes

In the present work, we suggest a novel method for obtaining interpolyelectrolyte complex (IPEC) by free radical polymerization in water–salt dispersions of polyelectrolyte complexes (PECs) based on an anionic polyelectrolyte (sodium salt of poly (2-acrylamido-2-methyl-1-propanesulfonic acid) (PAMPS-Na)) and a cationic surfactant ((11-acryloyloxy) undecyl)-trimethylammonium bromide (AUTAB), as well as on PAUTAB cationic comb-like polyelectrolyte and AMPS-Na monomer. IPEC consisting of PAMPS and PAUTAB was obtained by two ways. The first one is polymerization of surface active monomers AUTAB in the presence of PAMPS, and the second one is polymerization of AMPS monomers in the presence of PAUTAB. Molecular hydrodynamics methods were used to determine the molecular properties of initial components, polyelectrolyte complexes (PECs), and IPECs. Analysis of the dependence between translational friction coefficient of macromolecules and their molecular masses (which takes into account excluded-volume effects) allowed us to determine the Kuhn segment length of PAMPS-Na macromolecule (A=6nm). Stable polyelectrolyte complexes, PEC, (PAMPS–AUTAB and PAUTAB–AMPS) were obtained by mixing solutions of components at low concentrations in equimolar ratios; polymerization of their low molecular weight components was carried out for the purpose of preparing IPECs. Comparison between scattered light intensity distributions measured for PEC and IPEC demonstrated that in IPEC solutions, only large aggregates of complex molecules are present, while in PEC solutions, two peaks were observed (those corresponding to diffusion of individual PECs and their aggregates). When concentrations of PEC components exceed 3.4mM, polymerization results in the formation of IPEC precipitate which was studied by small angle X-ray scattering. It was found that the IPEC based on PAMPS-Na forms a film with hexagonal packing, and the PAUTAB-based IPEC forms a lamellar film.

Improvement in Salt-Tolerance of Aqueous Magnesium Hydroxide Suspensions by Comb-Like Polyelectrolyte

The rheological behavior and stability of aqueous magnesium hydroxide (Mg(OH)2) suspensions were studied in the presence of comb-like polyelectrolyte, namely, sodium salts of poly(acrylic acid)-poly(ethylene oxide) (NaPAA–PEO) at high ionic strength. Rheological, sedimentation, and zeta potential measurements were conducted on Mg(OH)2 suspensions to assess the dispersing ability of NaPAA–PEO. The adsorption behavior of NaPAA–PEO on the surfaces of Mg(OH)2 particles was investigated by the adsorption isotherm measurements. The interparticle interactions were calculated by using the Hamaker 2 program to evaluate the effect of NaPAA–PEO dosage on the stability of suspensions. The results indicated that NaPAA–PEO, which is insensitive to ionic strength variation, could improve the salt-tolerance of Mg(OH)2 suspensions and provide effective electrosteric stabilization, thus facilitating the production process and application of Mg(OH)2 suspensions over broad range of ionic strength.

Perfluoro-alcohol-induced complex coacervates of polyelectrolyte-surfactant mixtures: phase behavior and analysis.

Perfluorinated alcohols and acids such as hexafluoroisopropanol (HFIP), trifluoroethanol, trifluoroacetic acid, pentafluoropropionic acid, and heptafluorobutyric acid induce coacervation and phase separation in aqueous solutions of a wide variety of individual and mixed amphiphiles [ Khaledi Langmuir 2013 , 29 , 2458 ]. This paper focuses on HFIP-induced complex coacervate formation in the mixtures of anionic polyelectrolytes, such as sodium salt of poly(methacrylic acid) (PMA) or poly(acrylic acid) (PAA) and cationic surfactants of alkyltrimethylammonium bromides. In purely aqueous media and over a wide concentration range, mixtures of PMA and CTAB form the catanionic complex (CTA(+)PM(-)) that is insoluble in water (white precipitate). Upon addition of a small percentage of HFIP, the mixture goes through phase transition and formation of two distinctly clear liquid phases. The phase diagram for the HFIP-PMA-CTAB coacervate system was studied. The coacervate volume was determined as a function of system variables such as charge ratio as well as total and individual concentrations of the system components. These results, combined with the chemical composition analysis of the separated aqueous top-phase and coacervate bottom-phase, shed light on the coacervation mechanism. The results suggest that exchange of counterions and ion-pair formation play critical roles in the coacervation process. This process facilitated by HFIP through solvation of the head groups and dehydration of the hydrophobic moieties of the catanionic complex. Because of the presence of HFIP, coacervation occurs over a wide range of concentrations and charge ratios of the oppositely charged polyelectrolyte and surfactant.

Drying dissipative patterns of aqueous solution of poly(methacrylic acid) and its salt neutralized half

Drying patterns of poly(methacrylic acid) (HPMA) and its salt neutralized half with sodium hydroxide (NaHPMA) were studied on a cover glass, a watch glass, and a glass dish. The patterns of HPMA and NaHPMA are compared with the previous observation of sodium salt of poly(methacrylic acid), NaPMA (Okubo et al. Colloid Polym Sci 287:1155–1165, 2009). HPMA and especially NaHPMA are hygroscopic, and only the macroscopic patterns were observed. However, microscopic patterns were not observed clearly especially for NaHPMA in the room atmosphere. The hygroscopy of the dried films was in the order NaPMA NaHPMA > NaPMA. The magnitude of S values of NaPMA was similar to that of poly(ethylene glycol) (PEG). HPMA, NaHPMA, and NaPMA were grouped into E, A, and A, respectively, among six groups of solutes A to F.

Synthesis and optical, electrical, and thermoelectric properties of sodium salts of polyaniline sulfonic acid

Sodium salts of poly(aniline-5-sulfonic acid) (PAS), The PAS(Na)s, were obtained by the reaction of PAS with NaOH in water. The degree of sodium sulfonation of the PAS(Na)s depended on the feed amount of NaOH. The absorption peak of the PAS(Na)s, corresponding to an exciton transition generated by self-doping in the polymer backbone, decreased with the number of sodium sulfonated units. The PAS(Na)s were subjected to electrochemical oxidation, and the two oxidation peaks shifted to a lower potential as the degree of sodium sulfonation increased. The electrochemical reaction was accompanied by electrochromism. Thermoelectric measurements of the PAS(Na)s suggested that the majority of carriers were holes. The Seebeck coefficients (S′s) of the PAS(Na)s increased as the degree of sodium sulfonation of the polymers increased.

Adsorption of water to double-network polymers having a hierarchical structure

Double-network hydrogels (DN-gels) have cross-linked aqueous polymer networks which result in unique mechanical properties [1,2]. Although the structure of the hydrophilic polymer networks have been previously determined [3,4,5], it was not clear how water molecules are adsorbed to the polymer network. We prepared freeze-dried DN-gels (DN-polymers) made of polyacrylamide and sodium salt of poly(2-acrylamido-2-methylpropane sulfonic acid), and small-angle neutron scattering (SANS) experiments were conducted to determine the humidity dependence of the nanoscale structure. The SANS results show that water molecules adsorb on larger structures than the mesh size of polymer networks at low relative humidity (RH), and adsorb gradually on the segmental scale of polymers with increasing RH.

Molecular dynamics study of linear and comb-like polyelectrolytes in aqueous solution: effect of Ca2+ ions

All-atom molecular dynamics simulations were employed to provide microscopic mechanism for the salt tolerance of polyelectrolytes dispersants. The conformational variation of polyelectrolytes and interactions between COO− groups and counterions/water molecules were also studied via radius of gyration and pair correlations functions. Sodium polyacrylate (NaPA) and sodium salts of poly(acrylic acid)–poly(ethylene oxide) (NaPA–PEO) were selected as the representative linear and comb-like polyelectrolyte, respectively. The results show that Ca2+ ions interact with COO− groups much stronger than Na+ ions and can bring ion-bridging interaction between intermolecular COO− groups in the NaPA systems. While in the NaPA–PEO systems, the introduced PEO side chains can prevent backbone chains from ion-bridging interactions and weaken the conformational changes. The present results can help in selecting and designing new-type efficient polyelectrolyte dispersants with good salt tolerance.

Characterization of modified styrene-co-2-acrylamido-2-methylpropane sulfonic acid magnetite nanoparticles

This work provides an insight into the effect of incorporating of magnetite nanoparticles on the rheology of fluids. In this respect, polymer-stabilized magnetite nanoparticles were obtained using sodium salt of poly (2-acrylamido-2-methylpropanesulfonate (PAMPS-Na). Monodisperse polymer coated magnetite nanoparticles Fe3O4/poly(styrene-AMPS) copolymer nanoparticles with diameters of 50–300 nm were prepared by radical polymerization in the presence of a ferrofluid coated with PAMPS-Na. The magnetic nanoparticles were easily separated in a magnetic field. The structure of the obtained magnetic nanoparticles was characterized by Fourier transform infrared spectroscopy (FTIR). The morphology and size of the magnetic nanoparticles were determined by transmission electron microscopy (TEM). FTIR and TEM revealed that the Fe3O4 nanoparticles were incorporated into the shells of poly(styrene-AMPS). Aqueous dispersed solutions of a charged hydrophobically modified Fe3O4/poly(styrene-AMPS) copolymer nanoparticles exhibit high viscosities even at low polymer concentrations (0.1 wt %), which is an interesting feature in connection with enhanced oil recovery. Effects of temperature and addition of sodium chloride on the viscosity properties of a semidilute dispersed solution of Fe3O4/poly(styrene-AMPS) copolymer nanoparticles are examined. The results indicated that Fe3O4/poly(styrene-AMPS) copolymer nanoparticles disclose strong interactions between magnetite and coated polymers of both PAMPS-Na and styrene-AMPS copolymers.