Nonpolar Solvent Systems Research Articles

Electrohydrodynamically Printed High‐resolution Arrays Based on Stabilized CsPbBr3 Quantum Dot Inks

AbstractHigh‐resolution perovskite quantum dots (PeQDs) arrays printed by electrohydrodynamic (EHD) inkjet printing show great application prospects in fields of micro‐display. Commonly, EHD inkjet requires a polar system for printing but it easily quenches the PeQDs. Meanwhile, the mismatch of solvent parameters causes uneven surface morphology and printing instability. In this work, a morphology uniformization strategy of a nonpolar binary solvent system of 1,3,5‐triethylbenzene and n‐tetradecane is proposed to prepare the didodecyldimethylammonium bromide (DDAB)/PbBr2 passivated PeQDs inks. When the solvent volume ratio is 5:5, the photoluminescence quantum yield (PLQY) of the ink reaches 94.06%. Benefiting from the match of boiling point, surface tension, and dielectric constant of ink, after the EHD inkjet printing, the line width of continuous smooth line arrays is as narrow as 2.0 µm and the coffee effect of dot arrays is well inhibited. Meanwhile, derived from the strong electrostatic interaction between the π‐electron structure of 1,3,5‐triethylbenzene and DDA+, the ink exhibits high stability. Moreover, the high‐resolution logo and miniature quick responsecode by EHD inkjet printing reach 22 718 dpi, far higher than that of the reported micro‐LED. This work paves the way for high‐resolution pixel arrays of micro‐display.

Antimicrobial Activity of Fruits and Vegetables Peels on Human Enteric Pathogen: A Review

Fruits and vegetables are widely employed in food production in India. Depending on their nature and cooking procedure, these products are consumed uncooked, half-cooked, or fully cooked, with or without peels. If these peel remnants are not further handled, they become garbage. But different studies conducted on peels revealed the presence of important metabolites, using the polar and carbohydrates, carotenoids, proteins, steroids, flavonoids, alkaloids, tannins, saponins, triterpenoids, and phlobatannin, coumarin, and other nonpolar solvent systems. These extracts are also having potent antimicrobial effects on enteric human pathogens. Various phytochemical elements have antibacterial, antioxidant, antiproliferative, and anti-inflammatory properties. etc. The current study examines the medicinal potential of Indian regional fruits and vegetable peels.

On valorization of solvent extracts of Terminalia arjuna (arjuna) upon DNA scission and free radical scavenging improves coupling responses and cognitive functions under in vitro conditions

Chronic diseases have been treated using the phytochemical concepts of ethnomedicinal plant-derived herbal products. Terminalia arjuna, a significant ethnomedicinal plant, was revisited and reconnoitred for antioxidant, free radical scavenging, and DNA nicking inhibiting activity under H2O2 conditions using 21 solvent extracts. Ferric reducing antioxidant power (FRAP), 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2′-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid, and nitrous oxide scavenging (%) were found to have a strong positive association and interaction (PCA 1 explains 84.54% variation) with ethanol bark (Etoh-AB) (Meoh-AF). TPC (144.67–1794 µg/mL GAE) and TFC (2.5–34 µM Fe(II)/g were highest in Etoh-AB. In a pattern of combined solvent extracts, Etoh-AB had the highest antioxidant capacity, accompanied by Etoh-AL ≥ Meoh-AB ≥ Dw-AF. With R2 = 0.94, the DNA nicking inhibition behaviour parameters relative front, relative quantity, band (%), and lane (%) formed a positive significant (p < 0.01) connection. For the first time, we show that Etoh-AB nicks supercoiled, circular plasmid DNA in a way that is comparable to normal antioxidants. Normal antioxidants with the ability to prevent DNA nicking include Butylated hydroxy anisole < Butylated hydroxy toluene < ascorbic acid < and Gallic acid. Gallic acid (m/z 170.0208 g/mol) and Ellagic acid (m/z 302.0063 g/mol were present in high concentrations in solvent extracts. 0.48 mg was found to be the effective concentration for inhibiting relative DNA nicking. The current study is the first of its kind to show that steroid concentrations are higher in bark fractions of acetone, ethanol, and methanol. Furthermore, T. arjuna solvent extracts provide a wealth of information on phytochemical profiling, antioxidant ability, and DNA nicking inhibition, which may be useful for exploring the natural way and further research to develop a remedy against geriatric chronic disease. Despite the fact that ethanol is very close to methanol in terms of solvent toxicity, the current study identified it as the preferred solvent. Thus, the current research revisits previous studies and explores the potentiality of non-polar and polar aprotic and polar protic solvent systems, which lend credence to bioactive compounds that may be useful in isolating and formulating safe and cost effective herbal medicament for livestocks and aquaculture, and drugs for deoxygenerative human diseases, and can also be investigated further to instil environmental frugality.

Rapid assembly of phosphate-bridged tetra-mannose by ionic liquid-supported oligosaccharide synthesis

An efficient ionic liquid-supported oligosaccharide synthesis (ILSOS) strategy was described for the synthesis of linear oligo-phosphomannan. A new cleavable benzyl carbamate-type IL supporter containing 5-aminopentanyl linker was designed as an acceptor IL tag to facilitate this synthesis. The chain elongation on IL tag was achieved by H-phosphonate chemistry, including condensation with α-mannosyl H-phosphonate, in situ oxidation reaction and subsequent deprotection. After four cycles, linear α-(1 → 6)-tetra-mannan phosphate was obtained with a total yield of 52.7% within 45 h. The IL tagged product exhibited a tunable solubility in polar and non-polar solvent systems that facilitate a chromatography-free purification in the assembly process. The IL tag could be easily removed after hydrogenolysis treatment after the final step, to afford an amine terminated linker at the reducing end of phosphoglycan for further conjugation with a carrier protein. This methodology offered an efficient and chromatography-free approach for the synthesis of phosphoglycan.

Anti-HIV-1 activity of quinic acid isolated from Helichrysum mimetes using NMR-based metabolomics and computational analysis

Helichrysum species are widely used in traditional medicine with potential against infectious diseases. Extraction of the aerial parts of 32 Helichrysum species was done using polar (methanol:water (1:1)) and non-polar (hexane, dichloromethane and acetone) solvent systems. Anti-human immunodeficiency virus (HIV) bioassays revealed that polar extracts of H. mimetes and H. chrysargyrum (2.5 μg/mL), polar and non-polar extracts of H. cephaloideum (25 μg/mL) and polar and non-polar extracts of H. zeyheri, H. setosum, H. platypterum and H. kraussii at (2.5 μg/mL), had greater than 90% inhibitory activity. The polar extract of H. mimetes (100 μg/mL) exhibited 55.93% reverse transcriptase (RT) inhibition as a possible indication of the mechanism of action. Proton NMR spectra of the polar extracts exhibited the presence of aromatic compounds and carbohydrate moieties. Principal component analysis (PCA) of the polar extracts showed clustering related to the activity of the extracts with good predictability scores (Q2 > 0.5). However, orthogonal projections to latent structures discriminant analysis (OPLS-DA) predictability of the model was low based on the Q2 at approximately 0.25. Quinic acid (QA) isolated from H. mimetes showed promising anti-RT activity (IC50 = 53.82 μg/mL) comparable to the positive drug control, doxorubicin (IC50 = 40.31 μg/mL). A molecular docking study revealed the probable binding site and conformation of QA within cavity 4, with a docking score of −8.03. The docking score of doxorubicin within cavity 4 was −7.87. These are the first reports of QA's HIV-1-RT activity, as well as doxorubicin's docking characteristics on this enzyme.

Synthesis and properties of novel acrylic polyester hyper-dispersant

3-Pentadecylphenyl acrylate (PDPA) was synthesized from renewable sources (the cashew nut shell liquid), by using a novel organic chemical intermediate that can be used to copolymerize with vinyl monomers. A novel acrylic polyester hyper-dispersant was prepared by polymerization of methacrylic acid (MAA), butyl acrylate (BA), and PDPA. The acrylic polyester hyper-dispersants were used to disperse titanium dioxide in non-polar solvent system, and the dispersion performance was studied. The viscosity and particle size of suspensions were affected by monomer ratio and molecular weight; the results showed that the optimum monomer ratio and molecular weight were MAA:BA:PDPA = 1:10:1.2 (wt%) and 6000, respectively. The optimum amount weight of MAA of acrylic polyester should be around 10% (wt%).

Physiochemical, optical and mechanical properties of poly(lactic acid) nanocomposites filled with toluene diisocyanate grafted cellulose nanocrystals

Although cellulose nanocrystals (CNCs) have been highlighted as a potential nano-reinforcement in polymer composites, the hydrophilic surface nature of CNCs limits their usage in the composite area due to the poor dispersibility of the CNCs in nonpolar solvent systems.

Development of Tailored Porous Microstructures for Infiltrated Catalyst Electrodes by Aqueous Tape Casting Methods

Recent activities in SOFC research have shown the technique of impregnating fine catalyst structures into porous scaffolds to be an extremely promising route of development. Electrodes made in this way have shown promising performance with improvements in power density, carbon tolerance, redox tolerance and potentially sulphur tolerance. To gain the best cell performance it is likely that a supported electrolyte design will be favoured with the scaffold being fabricated by economically viable and scaleable techniques such as tape casting. It is clear that in optimising the advantages offered by the infiltration technique there will be an obvious link between the morphology of the porous scaffold and the infiltrated catalyst which is supported upon it. At present a significant amount of tape casting techniques are based around non-polar solvent systems. The solvents used in these systems, such as methyl ethyl ketone and toluene, can be quite aggressive and so limit the type of polymeric based pore former which can be employed to create porosity. There are also significant health and environmental issues with the use of such systems, such as flammability in exhaust systems at larger production scales and they are also coming under increasingly tight legislation with regards to handling, worker exposure and disposal. Minimising these make development of an aqueous system an attractive option. However the application of aqueous systems is not without issue. Attaining stable particle dispersions can be trickier due to the polar nature of the solvent leading to increased dipole interaction between slurry constituents and increased sensitivity to changes in pH. Furthermore the slurry can be more susceptible to local environmental changes such as temperature and humidity resulting in inconsistencies in tape quality. These factors have led to a slow uptake of aqueous systems in technical ceramic processing. However the potential benefits of aqueous systems for this application, such as a the potential for a far larger range of pore forming materials which may be employed to create specific pore morphologies, secondly the significantly reduced environmental burdens, such as exhaust handling, worker exposure and disposal, make their development for the production of porous scaffolds a valuable goal. Recent and ongoing activities to develop such systems at University of St Andrews will be described in this paper. A number of pore forming systems are under investigation, acrylic microspheres, rice starch, styrene-acrylic latex and sodium alginate, the latter is of additional interest due to its ability to cross-link allowing gel-casting techniques to be explored. Tapes have been manufactured using both YSZ and strontium and calcium doped lanthanum titanate (LSCT) as the ceramic phase with the pore formers used both individually and in combination with one another . The rheological behaviour of the wet tapes was assessed by rotational viscometry along with assessment of casting, drying and green properties. Tapes were fired in air over various times and temperatures with fired microstructures assessed by SEM examination and image analysis using “Image J” analytical software. Areas of discussion will be effects of ceramic particle type and size, the size ratio of pore former to ceramic particle, pore former type and loading and how these affect the interaction with other tape constituents both on the behaviour of the tape during processing and on the final fired morphology. How these relationships may be better understood and what implications they have in designing optimised porous structures in the future will also be discussed.

Investigating the Interaction Pattern and Structural Elements of a Drug-Polymer Complex at the Molecular Level.

Strong associations between drug and polymeric carriers are expected to contribute to higher drug loading capacities and better physical stability of amorphous solid dispersions. However, molecular details of the interaction patterns and underlying mechanisms are still unclear. In the present study, a series of amorphous solid dispersions of clofazimine (CLF), an antileprosy drug, were prepared with different polymers by applying the solvent evaporation method. When using hypromellose phthalate (HPMCP) as the carrier, the amorphous solid dispersion system exhibits not only superior drug loading capacity (63% w/w) but also color change due to strong drug-polymer association. In order to further explain these experimental observations, the interaction between CLF and HPMCP was investigated in a nonpolar volatile solvent system (chloroform) prior to forming the solid dispersion. We observed significant UV/vis and (1)H NMR spectral changes suggesting the protonation of CLF and formation of ion pairs between CLF and HPMCP in chloroform. Furthermore, nuclear Overhauser effect spectroscopy (NOESY) and diffusion order spectroscopy (DOSY) were employed to evaluate the strength of associations between drug and polymers, as well as the molecular mobility of CLF. Finally, by correlating the experimental values with quantum chemistry calculations, we demonstrate that the protonated CLF is binding to the carboxylate group of HPMCP as an ion pair and propose a possible structural model of the drug-polymer complex. Understanding the drug and carrier interaction patterns from a molecular perspective is critical for the rational design of new amorphous solid dispersions.

Thermoplasmonics-assisted nanoheterostructured Au-decorated CuInS2 nanoparticles: Matching solar spectrum absorption and its application on selective distillation of non-polar solvent systems by thermal solar energy

In this work, enhanced broadband solar spectrum absorption and solar-thermal conversion efficiency (~ 8%) has realized and reported by Au-decorated CuInS2 nanoparticles, namely Au@CIS NPs. The morphologies, compositions and absorptions were characterized by high resolution transmission electron microscopy (HR-TEM), UV–vis spectrometer and Finite-Difference Time-Domain (FDTD) numeric methods. The Au@CIS NPs shows a distinguished absorption perfectly matching AM1.5G solar spectrum, compared with pure Au, CIS and CIS–Au mixture nanoparticles (NPs) owing to near field plasmonic-assisted effect. In addition, the Au@CIS NPs proves its practical applications on selective distillation in non-polar solvent systems, for which the selective distillation of methylcyclohexane from toluene as an example was demonstrated. The approach can evoke future developments of plasmonic-assisted heterostructure in nanoscale for thermal solar energy harvesting application.

Phytochemical screening and antimicrobial evaluation of the methanol extract and fractions of the leaves of &lt;i&gt;Piper umbellatum&lt;/i&gt; Linn (Piperaeceae)

Piper umbellatum is widely distributed tropical plant species. The plant has been reported to possess an array activity including anti-inflammatory, antioxidant, antifungal, analgesic and skin protection. It is consumed as a vegetable and used ethnomedicinally in the treatment of stomach pain in Edo state, Nigeria. The antimicrobial property of the plant is being advocated. This present study aims at evaluating the phytochemistry of the methanol extract of P. umbellatum including analytical thin layer chromatography of the extract. This study evaluated the antimicrobial activity of the methanol extract of P. umbellatum as well as the n-butanol; n-hexane and chloroform fractions of the extract obtained by partitioning the methanol extract using clinical isolates in agar dilution technique. This study also went further to determine the minimum inhibitory concentration (MIC) of the methanol extract and the n-hexane fraction of the extract. Phytochemical screening of the dry leaves indicated the presence of carbohydrates, cardiac glycosides, saponins, tannins and alkaloids. TLC revealed that a non-polar solvent system is preferable for isolation. The methanol extract, n-hexane fraction and n-butanol fractions inhibited all the test microorganisms at the doses used. The MIC for both the methanol extract and n-hexane fraction were found to be &lt;25mg/ml. This study therefore confirms the antimicrobial activity of Piper umbellatum.Keywords: Piper umbellatum; Methanol extract; Antimicrobial activity; Phytochemistry; Chromatography

Lewis Acid‐Catalyzed Synthesis of Hyperbranched Polymers Based on Glycerol and Diacids in Toluene

AbstractExamples of monomeric glycerol‐derived hyperbranched polyesters produced in a nonpolar solvent system are reported here. The polymers were made by the Lewis acid [dibutyltin(IV) oxide]‐catalyzed polycondensation of glycerol with either succinic acid [n (aliphatic chain length) = 2], glutaric acid (n = 3), or azelaic acid (n = 7) in toluene. Poly(glycerol–diacid)s were recovered in yields as low as 65% and as high as 95%. The polyesters were characterized by gas chromatography to determine the extent of reaction and by gel permeation chromatography to determine molecular weight, polydispersity index, and degree of polymerization. None of the conditions explored gave 100% conversion but products could be recovered in greater than 97.8% purity. Gelation and low conversion were observed, respectively, for 24‐ and 10‐h polyesterifications of glutaric acid and glycerol (2:1 molar ratio) performed at 155 °C when the standard (neat) synthetic protocol was employed. Gelation was avoided and conversion improved when esterifications were performed in quasi‐melt solutions with toluene. The optimal reaction conditions to produce polymers with high conversion and high molecular weight before the onset of gelation were observed for 24‐h esterifications in toluene at 155 °C (2:1 molar ratio of glutaric acid/glycerol) and 135 °C (1:1 molar ratio of reactants). Expanding on the success of those findings, it was determined that gelation could be avoided for each of the three diacids studied. When all other conditions were held constant, in the absence of gelation, degree of polymerization increased with decreasing aliphatic chain length of the diacid.

Synthesis and characterization of amphiphilic block copolymers of methyl methacrylate with poly(ethylene oxide) macroinitiators formed by atom transfer radical polymerization

AbstractAmphiphilic ABA triblock copolymers of poly(ethylene oxide) (PEO) with methyl methacrylate (MMA) were prepared by atom transfer radical polymerization in bulk and in various solvents with a difunctional PEO macroinitiator and a Cu(I)X/N,N,N′,N″,N″‐pentamethyldiethylenetriamine catalyst system at 85°C where X=Cl or Br. The polymerization proceeded via controlled/living process, and the molecular weights of the obtained block copolymers increased linearly with monomer conversion. In the process, the polydispersity decreased and finally reached a value of less than 1.3. The polymerization followed first‐order kinetics with respect to monomer concentration, and increases in the ethylene oxide repeating units or chain length in the macroinitiator decreased the rate of polymerization. The rate of polymerization of MMA with the PEO chloro macroinitiator and CuCl proceeded at approximately half the rate of bromo analogs. A faster rate of polymerization and controlled molecular weights with lower polydispersities were observed in bulk polymerization compared with polar and nonpolar solvent systems. In the bulk polymerization, the number‐average molecular weight by gel permeation chromatography (Mn,GPC) values were very close to the theoretical line, whereas lower than the theoretical line were observed in solution polymerizations. The macroinitiator and their block copolymers were characterized by Fourier transform infrared spectroscopy, 1H‐NMR, matrix‐assisted laser desorption ionization time‐of‐flight mass spectrometry, thermogravimetry (TG)/differential thermal analysis (DTA), differential scanning calorimetry (DSC), and scanning electron microscopy (SEM). TG/DTA studies of the homo and block copolymers showed two‐step and multistep decomposition patterns. The DSC thermograms exhibited two glass‐transition temperatures at −17.7 and 92°C for the PEO and poly(methyl methacrylate) (PMMA) blocks, respectively, which indicated that microphase separation between the PEO and PMMA domains. SEM studies indicated a fine dispersion of PEO in the PMMA matrix. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 97: 989–1000, 2005

Studies on the ion-association of methylene blue and salicylic acid in neat and mixed binary solvents

Thiazine dye, methylene blue forms 1:1 ion-associate with salicylic acid in aqueous phase and the ion-associate can be extracted in a series of non-polar non-coordinating solvent systems. The influence of different parameters on the process of ion-association has been studied. The suitability of a number of phenolic precursors for the formation of ion-associate with methylene blue has been tested. Charge-transfer absorption band of the dye molecules in relation to ion-pair has been followed in a sequence of neat and mixed binary solvents and the dependence of the absorption maxima has been found to correlate well with the solvent polarity.

A Polar−Nonpolar, Acetic Acid/Heptane, Solvent Medium for Degradation of Pyrene by Ozone

Pyrene of natural and anthropogenic sources is one of the toxic, mutagenic polycyclic aromatic hydrocarbons (PAHs) listed as priority pollutants. The recalcitrant nature of pyrene and other PAHs lies in part in their low solubility in water, rendering them less susceptible to chemical or biological degradation. This work investigates the use of a polar−nonpolar (PNP) solvent system, in conjunction with ozonation, to overcome this remediation obstacle. The PNP solvent system consists of equal portions of polar acetic acid and nonpolar heptane. The heptane component enables high concentrations of pyrene to be dissolved, while the acetic acid keeps subsequently formed polar intermediates and byproducts in solution. This PNP solvent system maintains effective exposure of all compounds to aqueous ozone throughout the course of reaction and prevents the formation of solid precipitation. Following ozonation, the solvent system is added with a small amount of water that results in the formation of two distinct ph...

Application of the mobile order thermodynamics to predict the solubility of solid hydrocarbons in pure solvents and nonpolar binary solvent systems

This work extends the application of the thermodynamics of mobile order from the solubility prediction in single solvents to that in binary solvent blends without additional new parameters. Predicted solubilities are compared to the experimental values for solid n-octadedane, n-nonadecane and naphthalene in various non-polar, polar and hydrogen-bonded pure solvents as well as in 22 two-component solvent systems involving only non-specific interactions. Absolute average deviations between predicted and experimental results do not exceed 10 % in single solvents and 5 % in binary mixtures. The solubility profiles versus solvent composition show that the solubilities are additive in mixtures of solvents whose interaction characteristics are very similar.

Are Polar Organometallic Compounds “Carbanions”? The Gegenion Effect on Structure and Energies of Alkali‐Metal Compounds

AbstractPolar organometallic compounds such as alkyllithium compounds or Grignard reagents often are conceived as “carbanions”, although it is well known from experiments that the metal gegenions may have a strong, and often directing, influence on the reactivity (for example, the basicity vs. the nucleophilicity) of the “carbanion”. This demonstrates that “carbanions” are tightly associated ion pairs, at least in commonly used less polar or nonpolar solvent systems like ethers or hydrocarbons. However, despite about ninety years of widespread application of these organometallic compounds as bases or nucleophilic reagents, the role of the gegenion is not yet understood fully. The focus of this review is on the inherent influences of the metal gegenion on the structures, reaction energies, and activation barriers of some representative alkali‐metal compounds. While most comparisons of physical and chemical properties determined experimentally for Group I compounds are precluded due to different substituents, solvents, ligands, etc., ab initio calculations of model compounds can yield intrinsic data that are useful for a better understanding of chemical behavior. For this reason, most of the data reviewed in this article are based on quantum chemical calculations, which are compared with experimental data where available.

Chromatography on Poly-RP and its cyano and diol derivatives using both polar and non-polar solvent systems

A 4-μm polystyrene-divinylbenzene resin, Poly-RP CO, was synthesized for high-performance liquid chromatography. The surface of this resin was functionalized with cyano and diol groups that are capable of enhancing the selectivity and capacity of the base resin. Chromatography was performed with traditional polar solvent systems, such as acetonitrile-water, and also with non-polar solvent systems, such as dichloromethane-hexane; the latter solvent system can give separations that are otherwise difficult to achieve with acetonitrile-water. Good separations of simple isomer mixtures were achieved on these resins.

The Relationship Between Chemical Structure and the Logarithm of the Partition Coefficient

AbstractThe relationship between chemical structure of a solute and the logarithm of its partition coefficient (log P) between the aqueous and a nonpolar phase is poorly understood. We have recently shown that the variation in log P data for 50 low molecular‐weight organic solutes in 6 aqueous‐non‐polar solvents is a function of two structural features. The main feature accounts for ≈︁60% of the variation in the log P data, and is uniformly weighted in all 6 nonpolar solvent systems. This suggests that it is related to the aqueous solution properties of the solute. The first feature is termed the isotropic surface area, or the surface area associated with the nonpolar portion of the solute when the solute is considered to be a hydrated complex. The hydrated solute complex is termed a supermolecule with waters of hydration occupying hydrogen bonding sites on the functional groups of the solute. Empirical rules for formation of the super molecule are discussed.In this report the analysis is extended to log P data for 72 solutes in the 6 nonpolar solvent systems. The results of the analysis are essentially unchanged for this more extended data set and the second factor is tentatively identified. The second structural feature accounted for ≈︁35% of the variation in the log P data was not equally weighted in all solvents and is difficult to interpret structurally.

Associating polymers in a well‐defined extensional flow field: Influence of solvent quality and polymer concentration

AbstractThe conformational response of an associating‐type random coil macromolecule in solution was investigated utilizing an opposing jet device. This device, capable of generating a well‐defined elongational flow field, is quite useful for probing intra‐ and intermolecular interactions of lightly sulfonated polystyrene ionomers in both nonpolar and polar solvent systems. Below a critical concentration in nonpolar media, such ionomers qualitatively follow trends predicted by dilute solution theory, although intramolecular ionic associations markedly increase the critical elongational shear rate. With further increases in concentration, the extensional behavior is determined by the initial formation of relatively strong intermolecular associations. At even higher polymer concentrations, a third regime is observed where the conformational relaxation process becomes even more facile. On the contrary, in a polar solvent, the conformational relaxation process is markedly enhanced (i.e., critical elongational shear rate is reduced) due to the polyelectrolyte effect, i.e., dissociation of a significant level of the counterions. The effect of this dissociation process influences the relaxation process over the entire concentration region examined. These findings are compared directly with solution rheology, where in low polarity solvents the reduced viscosity is markedly diminished by ion pair‐type interactions, and in more polar environments the reduced viscosity is enhanced due to the dissociation of the counterions from the vicinity of the chain backbone.