Inorganic Counterions Research Articles

Effect of different counterions on the self-assembly structures and properties of imidazole based ionic liquids surfactant: A molecular dynamics study

Self-assembly of ionic liquids (ILs) in solution has attracted wide attention due to their potential applications in various fields. The nature of counterions, especially aromatic counterions, will significantly affect the aggregation and morphological properties of ILs surfactants. In this paper, molecular dynamics (MD) simulations are applied to study the influence of three organic and inorganic counterions (phenolate (PO−), benzoate (BZ−), and Cl−) on the micellar structure of imidazolium (C14mim+) based ILs surfactant in aqueous solutions. Three micelles all possess prolate shape. The PO−, BZ−, and Cl− ions hardly affect the orientation and length of hydrophobic chains in micellar interior. Hydration numbers and average radial density distributions analyses show that interactions between micelles and water molecules are different in studied micelles. Surrounding water molecules penetrate into the deepest region in [C14mim][Cl] micelle. However, adsorbed Cl− ions are mainly located on micellar surface, not penetrating into micellar interior. Due to the intrinsic hydrophobicity of organic ions, both PO− and BZ− ions enter into deeper positions in micelles. Unlike Cl− ions, there exist π-interactions between adsorbed PO− and BZ− ions themselves. One interesting finding is that adsorbed PO− and BZ− ions can make micelle radius (Rg) increase but make solvent accessible surface area (SASA) decrease. Conversely, adsorbed Cl− ions make both Rg and SASA increase. Three MD models for different C14mim+ based micelles are proposed.

Catalytic response and molecular simulation studies in the development of synthetic routes in trimeric triaryl pyridinium type ionic liquids

Under conventional and silica-supported Muffle furnace methods, water-soluble substituted trimeric triaryl pyridinium cations with various inorganic counter anions are synthesized. The solvent-free synthesis method is superior to the conventional method in terms of non-toxicity, quicker reaction times, ease of workup, and higher yields. Trimeric substituted pyridinium salts acted as excellent catalytic responses for the preparation of Gem-bisamide derivatives compared with available literature. To evaluate the molecular docking, benzyl/4-nitrobenzyl substituted triaryl pyridinium salt compounds with VEGFR-2 kinase were used with H-bonds, π–π stacking, salt bridges, and hydrophobic contacts. The results showed that the VEGFR-2 kinase protein had the most potent inhibitory activity. Intriguingly, the compound [NBTAPy]PF6- had a strongly binds to VEGFR-2 kinase and controlled its activity in cancer treatment and prevention.

J-aggregates of 5,10,15,20-tetrakis(4-sulfonatophenyl)-porphyrin. An overview of the supramolecular self-assembling mechanism

Under acidic conditions and at high ionic strength or in the presence of templating species, 5,10,15,20-tetrakis(4-sulfonatophenyl)porphyrin (TPPS[Formula: see text] self-organizes into J-aggregates. In these species, the porphyrins align in a general edge-to-edge geometry, responsible for their peculiar optical properties. The self-assembling process is hierarchical, and the kinetics are strongly dependent on the mixing protocols. In the case of sigmoidal profiles, the kinetic data have been treated using a model proposed in the literature by R.F. Pasternack. Accordingly, an autocatalytic growth with the formation of an [Formula: see text]-mer of porphyrin units is the rate-determining step (RDS) leading to the eventual J-aggregates whose size spans from nano- up to the micro-scale. The impact of different experimental parameters, together with inorganic counter-anions, and various cationic and anionic species (organic anions, metal ions, porphyrins, and metal complexes) will be reviewed.

New salts of teriflunomide (TFM) – Single crystal X-ray and solid state NMR investigation

New salts of teriflunomide TFM (drug approved for Multiple Sclerosis treatment) with inorganic counterions: lithium (TFM_Li), sodium (TFM_Na), potassium (TFM_K), rubidium (TFM_Rb), caesium (TFM_Cs) and ammonium (TFM_NH4) were prepared and investigated employing solid state NMR Spectroscopy, Powder X-ray Diffraction PXRD and Single Crystal X-ray Diffraction (SC XRD). Crystal and molecular structures of three salts: TFM_Na (CCDC: 2173257), TFM_Cs (CCDC: 2165288) and TFM_NH4 (CCDC: 2165281) were determined and deposited. Compared to the native TFM, for all crystalline salt structures, a conformational change of the teriflunomide molecule involving about 180-degree rotation of the end group, forming an intramolecular hydrogen bond N–H⋯O is observed. By applying a complementary multi-technique approach, employing 1D and 2D solid state MAS NMR techniques, single and powder X-ray diffraction measurements, as well as the DFT-based GIPAW calculations of NMR chemical shifts for TFM_Na and TFM_Cs allowed to propose structural features of TFM_Li for which it was not possible to obtain adequate material for single crystal X-Ray measurement.

Enhanced electrorheological effectiveness and temperature effect of suspensions based on poly(ionic liquid)s neutralized with mixed counterions

A series of random co-poly(ionic liquid)s (co-PILs) neutralized with mixed counterions of organic bis(trifluoromethane sulfonyl)imide ([TFSI]) and inorganic tetrafluoroborate ([BF 4 ]) of different mole ratio had been synthesized for use as electrorheological (ER) particles. The temperature-modulated ER effect of the co-PIL particles had been investigated and compared with that of homo-poly(ionic liquid)s neutralized with single organic [TFSI] counteranions. This work demonstrated that the ER effectiveness and temperature effect of electrorheological fluid based on neat organic counteranions-typed PILs can be significantly improved by a simple substitution of inorganic counteranions with a suitable mole ratio. The higher electrorheological effectiveness with suppressed leakage current density and enhanced temperature stability originated from that the substitution of inorganic counteranions for organic counteranions could systematically elevate the glass transition temperature and modulate the activation energy of ion movement in PILs matrix. Linear polymeric ionic liquids (PILs) neutralized with mixed counteranions of organic ([TFSI]) and inorganic ([BF 4 ]) could exhibit higher ER effectiveness and broader working temperatures range than the analogous PILs neutralized with single organic counteranions. • PILs containing organic and inorganic counterions of various mole ratio was prepared for use as electrorheological particles. • Partial replacement of [TFSI] by [BF 4 ] could improve the electrorheological effectiveness and thermal stability of PILs. • Partial replacement of [TFSI] by [BF 4 ] could modulate the glass temperature and ionic shifting activation energy of PILs.

Simple grinding for the synthesis of monomeric, dimeric, and trimeric pyridinium salts and its photophysical studies

AbstractSynthesis of water‐soluble‐substituted pyridinium cation which is attached with base sensitive fluorophore peripheral units with different inorganic counter anions under conventional/silica‐supported Muffle furnace methods. Solvent‐free synthetic approach has more merits than the conventional method, such as non‐toxic, shorter reaction time, easy workup procedure without purification process, and higher yields. Ultraviolet–visible spectra were recorded in neutral, acidic, and alkaline medium; it showed greater red shift in alkaline medium compared with neutral and acidic pH medium.

High-Energy-Density Materials: An Amphoteric N-Rich Bis(triazole) and Salts of Its Cationic and Anionic Species.

The synthesis and characterization of the N-rich bis(triazole) compound 1H,4′H-[3,3′-bis(1,2,4-triazole)]-4′,5,5′-triamine (C4H7N9) with a N content of 69.6% by weight is reported. The compound exhibits a rich acid–base behavior because it can accept up to two protons, forming a monocation and a dication, and can lose one proton, forming an anion. Measurement of the acid constants has shown that there exist well-defined pH intervals in which each of the four species is predominant in solution, opening the way to their isolation and characterization by single-crystal X-ray analysis as salts with different counterions. Some energetic salts of the monocation or dication containing oxidizing inorganic counterions (dinitramide, perchlorate, and nitrate) were also prepared and characterized in the solid state for their sensitivity. In particular, the neutral compound shows a very remarkable thermal stability in air, with Td = 347 °C, and is insensitive to impact and friction. Salts of the dication with energetic counterions, in particular perchlorate and nitrate, show increased sensitivities and reduced thermal stability. The salt of the monocation with dinitramide as the counterion outperforms other dinitramide salts reported in the literature because of its higher thermal stability (Td = 230 °C in air) and friction insensitiveness.

Recycling Thermoset Epoxy Resin Using Alkyl-Methyl-Imidazolium Ionic Liquids as Green Solvents.

Herein, a solvent-based green recycling procedure is reported for recycling thermoset epoxy resins (TERs) and carbon fiber reinforced epoxy composites (CFRECs) employing ionic liquids (ILs) and alcohols under mild conditions. With melting points less than 100 °C, ILs are defined as organic salts, typically composed of bulky cations with organic or inorganic counteranions. As a result of their unique physical properties such as low vapor pressure, relatively high thermal stability, and multifunctional tunability, these solvents are often classified as “green solvents” as compared to traditional organic solvents. In this study, swelling and dissolution of TER are evaluated in the presence of pure alkyl-methyl-imidazolium ILs, alcohols, and various mixtures of these co-solvents to determine their swelling and depolymerization capacity at mild temperatures in the absence of catalysts. In these studies, three ILs with different alkyl lengths were evaluated: 1-butyl-3-methyl imidazolium chloride ([BMIm][Cl]), 1-hexyl-3-methyl imidazolium bromide ([HMIm][Br]), and 1-octyl-3-methyl imidazolium bromide ([OMIm][Br]) along with two alcohols: ethylene glycol (EG) and glycerol (Gly). The highest swelling capacity of TER at 150 °C was achieved by a combination of [BMIm][Cl] and EG. In addition, swelling and dissolution of TER were evaluated in the presence of several anion variants of 1-butyl-3-methyl-imidazolium ILs with EG. Complete dissolution of both TERs and CFRECs was achieved in 150 min (2.5 h) at 150 °C under atmospheric pressure. Finally, recovery and reuse of the recycled monomer after dissolution were examined. Recovered epoxy monomers employed to synthesize a recycled TER exhibited similar mechanical properties to the parent TER. In addition, it was demonstrated that carbon fibers could be successfully recovered from CFREC using the recycling method detailed in this manuscript.

Effects of cationic counterions and surfactant on viscosity of an amino acid-based surfactant system

Many sulfate-free and amino acid-based surfactant systems for personal care formulations do not respond to thickening with salt and/or amphoteric cosurfactants as readily as traditional sulfate-based formulations. Although this phenomenon is generally understood to be associated with large headgroups, the mechanistic basis for the difference is poorly understood. To address this question we have combined an empirical approach involving traditional determination of low shear viscoelasticity with a state-of-the-art mesoscopic analysis of micelle dynamics enabled by high frequency rheological measurements obtained optically (Zou and Larson, Journal of Rheology 2014, 58 (3), 681-721) We studied the impact of various organic and inorganic counterions as well as a cationic surfactant as alternative thickening agents for a model formulation of sodium lauroyl sarcosinate (SLSar) and cocamidopropyl hydroxysultaine (CAHS). These additives include lithium chloride (LiCl), sodium chloride (NaCl), L-arginine (Arg), triethanolamine (TEA), trimethylphenylammonium chloride (TMPAC), and cetyltrimethylammonium chloride (CTAC). The zero-shear viscosity for all systems studied was obtained using steady-state rheology at varying concentration and pH. The viscoelastic properties of systems containing an effective thickener (CTAC 1%) and an ineffective one (LiCl 1%) were obtained over a frequency range of 1–105 rad/s and subjected to the Zou and Larson analysis. The analysis showed that the high viscosity in the CTAC 1% system was associated with the combination of a high plateau modulus and a long relaxation time. The low viscosity in LiCl 1% system was attributable to the fast breakage time and high breakage rate constant. The latter result was consistent with findings from a previous study comparing the SLSar/CAHS system to a sodium lauryl ether sulfate/cocamidopropyl betaine (SLES/CAPB) formulation.

Cationic (Basic) dye complex pigments

Abstract Cationic (or basic) dye complex pigments are classical organic pigments obtained from water-soluble cationic dyes for textiles, mainly of triarylmethine (arylcarbonium ion) types, which are precipitated using large inorganic counterions, especially those derived from heteropolyacids such as phosphotungstomolybdic acid or, to a certain extent, using the counteranion derived from copper ferrocyanide. This range of pigments includes red, violet, blue and green products, offering brilliant shades, high color strength and good transparency. They are well suited to printing ink applications, although they provide only moderate levels of fastness properties. The pigments are synthesized by treating aqueous solutions of the dyes under highly controlled conditions with solutions of the heteropolyacids, prepared in situ. The copper ferrocyanide salts are obtained by treatment of potassium ferrocyanide with sodium sulfite in water, and subsequently with solutions of the cationic dye and copper (II) sulfate. The pigments are primarily used in inks for packaging and advertising materials. However, they have little use outside printing inks. Reflex or alkali blue pigments are structurally related cationic dye derivatives which are inner salts of the dye structures and are also used in printing inks.

Powerful tailoring effects of counterions of ammonium surfactants on the phase transitions of solvent-free DNA thermotropic liquid crystals

Solvent-free DNA-surfactant thermotropic liquid crystals (TLCs) are new developed soft biomaterials in recent years. The phase transition behaviors of these DNA TLCs could be regulated by the chain lengths of used double chain surfactants. While, the impact of counterions of ammonium surfactants on the phase transitions of DNA TLCs is still not clear. Herein, a series of ammonium surfactants with different counterions were prepared and put into use of fabrication of DNA TLCs. With inorganic counterions, the resulted DNA materials exhibit distinct decrease on the thermodynamic stability of LC states along with the size increase of counterions, while, the use of planar p-toluenesulfonate as counterion leads to remarkable increased LC thermostability for the resulted DNA material, due to the different interaction between counterions and surfactant layers. These observations indicate that the LC property of DNA-surfactant complexes could be conveniently tailored by using surfactants with designed counterions, providing a new strategy for designing advanced solvent-free biomaterials.

Assembling Lipoic Acid and Nanoclay into Nacre-Mimetic Nanocomposites

A facile strategy to obtain nacre-mimetic nanocomposite materials is presented. The proposed economically feasible and environmentally friendly process consists in fusing dynamic poly(lipoic acid) and montmorillonite (MTM) via a water evaporation method. Lipoic acid (LA), a naturally occurring molecule, can readily undergo thermal-, UV-, or (water) evaporation-induced dynamic ring-opening polymerization. This monomer has been equipped with various organic and inorganic counter cations, altering the physical properties of both the obtained poly(lipoate)s and the resulting nacre-like nanocomposites. The mechanical performance of the nanocomposites can be accordingly tuned from rigid and brittle to soft and ductile. Importantly, the composites containing triethanolammonium cations show enhanced ductility with an elongation at break up to around 16% when compared to other reported nacre-mimetic nanocomposites with similar MTM content (elongation at break usually below 10%). Moreover, the influence of MTM content on the mechanical properties of the nanocomposites is elucidated. Furthermore, the dynamic nature of the poly(lipoate)s and supramolecular architecture within the composites enables water-assisted self-healing of superficial scratches, as evaluated by optical microscopy, and closed-loop recycling for materials with up to 70 wt % MTM. Finally, the nanocomposites were found to exhibit flame retardancy.

Fabrication of Soft-Oxometalates {Mo132} Clusters With Novel Azobenzene Surfactants: Size Control by Micelles and Light.

Soft-oxometalates (SOMs) are colloid suspensions of superstructured assemblies of polyoxometalates (POMs) and are found to be very effective photo-catalysts in a number of chemical reactions. The stabilization of SOMs generally requires legends or stabilizers, e.g., polymers and surfactants. In this paper, a light responsive azobenzene surfactant, C10AZOC2N3, was developed and used to stable {Mo132} SOMs. Various techniques such as Dynamic light scattering, TEM, UV-Vis spectra and cyclic voltammetry were employed to characterize the experimental results. The outstanding structure-directing effect of surfactant self-assembly micelles in solution on inorganic counter-anions was demonstrated. Different amount of cyclohexane was solubilized into C10AZOC2N3 micelles to successfully control the size of {Mo132} SOMs cluster. Furthermore, the clusters exposed to UV light for a certain time can be served as a second trigger to control the size of SOMs due to the trans-cis conformation transition of surfactant molecules. The redox potentials of C10AZOC2N3-{Mo132} SOMs were investigated as the cluster size varied. Interestingly, the redox potential of {Mo132} was not affected by the cluster size, indicating that the presence of surfactant did not change the main function of {Mo132} as an electrochemical catalyst, but merely assisted in the size control of SOM aggregation.

Controllable enzymatic superactivity of α-chymotrypsin activated by the electrostatic interaction with cationic gemini surfactants.

Surfactant plays a critical role in enzymatic multi-functionalization processes. However, a deep understanding of surfactant-enzyme interactions has been lacking up until now due to the extreme complexity of the mixed system. This work reported the effect of cationic gemini surfactants, alkanediyl-α,ω-bis(dimethyldodecylammonium bromide) (C12CSC12Br2, S = 2, 6, and 10) on the enzymatic activity and conformation of α-chymotrypsin (α-CT) in phosphate buffer solution (PBS, pH 7.3). The enzymatic activity was assessed by the rate of 2-naphthyl acetate (2-NA) hydrolysis measured by UV-vis absorption. The superactivity of α-CT in the presence of C12CSC12Br2 appears in the concentration region below the critical micelle concentration (cmc) of the surfactant, and its maximum superactivity is correlated to the spacer length of C12CSC12Br2. Subtle regulation of the charge density of headgroups of the cationic surfactant can be achieved through partial charge neutralization of cationic headgroups by introducing inorganic counterions or oppositely charged surfactant, demonstrating that the electrostatic interaction plays the crucial role for emergence of the superactivity. The interaction between C12CSC12Br2 (S = 2,6, and 10) and α-CT was characterized by isothermal titration calorimetry (ITC), and the obtained endothermic enthalpy change indicates that the interaction induces the change in conformation and enzymatic superactivity. The methodologies of fluorescence spectroscopy, circular dichroism (CD), and differential scanning calorimetry (DSC) show that the gemini surfactants with different spacer lengths induct and regulate the secondary, tertiary and even fourth structures of the protein. The present work is significant to get deeper insight into the mechanism of the activation and denaturation of enzymes.

1,2,3-Triazole based poly(ionic liquids) as solid dielectric materials

1,2,3-triazole based polyionic liquids (PIL) are an emerging field among polymeric dielectrics in organic electronics. 1,2,3-triazole based PILs can be obtained from poly(4-vinylbenzylchloride) by copper-catalyzed azide-alkyne cycloaddition (CuAAC) ‘click’ reaction. The polymer architecture and the charge of the PILs can be manipulated by choosing a suitable alkyne, azide containing moiety, and by the alkylation of the 1,2,3-triazole group. Thus, we were able to prepare PILs carrying either inorganic (Na+ or Cl−) or the organic counterions 1-butyl-3-methyl-imidazolium (C4mim+) or 1-butyl-3-methyl-imidazolium (TFSI−). Metal-insulator-metal capacitors were fabricated and the dielectric properties were characterized through electrochemical impedance spectroscopy. The PILs demonstrated an increase in capacitance density with decreasing frequency, characteristic for the polarization of the polymer layer and electrical double layer formation. Substitution of inorganic counterions with organic counterions improved the transition frequency of the capacitors and the conductivity of the polymers. This was due to increased ion mobility and decreased glass transition temperatures.

Charge-by-Charge Ion Pairing Preserves Fluorescence Emission

In this issue of Chem, Flood and co-workers demonstrate spatially and electronically isolated cationic dyes in crystalline charge-by-charge ion-pairing systems based on sandwiched [2 + 1]-type anion complexes of a π-electronic cyanostar macrocycle; these dyes exhibit fluorescent colors and intensities similar to those in solution.

Studies on the synthesis, surface activity and the ability to form pH-regulated wormlike micelles with surfactant containing carboxyl group

In this article, a series of pH regulated surfactants with different hydrophobic chain length and carboxyl group molecular structure positions were designed and synthesized. The molecular structure of pH regulated surfactants was analyzed by mass spectrometry and 1 H NMR spectroscopy. The results of the surface activity test show that the pH regulated surfactants have lower surface tension, which indicates that it is easier to adsorb directionally at the gas-liquid interface and to aggregate in solution. Both inorganic and organic counterions can improve the viscosity of the system to some extent, but the viscosity-increasing ability of organic counterions is much higher than that of inorganic counterions. The results of rheology and dynamic light scattering show the transition from spherical micelles to wormlike micelles was observed when pH increased from 5 to 8 in the Docos-13-enoylamino-acetic acid (Gly-22)/Trimethylstearylammonium chioride (ODAC) system. The results of Cryo-transmission electron microscopy verify this result directly. Also, the experimental results show that the Gly-22/ODAC system has excellent pH cycle regulation performance, which can significantly reduce the application cost of the system. • A series of pH regulated surfactant were synthesized. • The transition from spherical micelles to wormlike micelles was realized when pH varied. • The Gly-22/ODAC system has excellent pH cycle regulation performance.

Aqueous solubility of beryllium(II) at physiological pH: effects of buffer composition and counterions

Beryllium ion elicits p53-mediated cell cycle arrest in some types of human cancer cells, and it is a potent inhibitor of GSK3 kinase activity. Paradoxically, Be2+ is regarded to have almost negligible aqueous solubility at physiological pH, due to precipitation as Be(OH)2. This study demonstrates that the interaction of Be2+ with serum proteins greatly increases its effective solubility. In typical serum-supplemented mammalian cell culture medium, Be2+ was soluble up to about 0.5 mM, which greatly exceeds the concentration needed for biological activity. Some biochemical studies require protein-free Be2+ solutions. In such cases, the inclusion of a specific inorganic counterion, sulfate, increased solubility considerably. The role of sulfate as a solubility-enhancing factor became evident during preparation of buffered solutions, as the apparent solubility of Be2+ depended on whether H2SO4 or a different strong acid was used for pH adjustment. The binding behavior of Be2+ observed via isothermal titration calorimetry was affected by the inclusion of sodium sulfate. The data reflect a “Diverse Ion Effect” consistent with ion pair formation between solvated Be2+ and sulfate. These insights into the solubility behavior of Be2+ at physiological and near-physiological pH will provide guidance to assist sample preparation for biochemical studies.

Impact of Aromatic Counter-Ions Charge Delocalization on the Micellization Behavior of Surface-Active Ionic Liquids.

The nature of counter-ions governs the micellar and structural characteristics of surface-active ionic liquids (SAILs). Especially, the introduction of aromatic counter-ions significantly increases their surface adsorption and induces the formation of various types of aggregates like prolate ellipsoidal micelles, rodlike micelles, vesicles, lamellars, etc. The present study reports the role of charge delocalization of two different aromatic counter-ions in the micellization behavior of their respective SAILs in aqueous medium. For this purpose, we have synthesized two SAILs, namely, 1-tetradecyl-3-methylimidzolium phenolate [C14mim][PO] and 1-tetradecyl-3-methylimidzolium benzoate [C14mim][BZ]. The O-atom of phenolate (PO-) possesses negative charge, which is delocalized on its phenyl ring. Conversely, the negative charge of benzoate (BZ-) is not delocalized on its phenyl ring. The more hydrophobic BZ- counter-ion increases the hydrophobic interactions and reduces the electrostatic repulsions more efficiently as compared to PO-, which results in a lower critical micelle concentration (cmc) of [C14mim][BZ] than that of [C14mim][PO]. Interfacial properties obtained by tensiometry reveal better surface activity and absorption efficiency of [C14mim][BZ] as compared to [C14mim][PO]. The increase of cmc and degree of counter-ion binding (β) with the rise of temperature for both SAILs has been observed by conductometry. The decrease in the polarity of pyrene microenvironment explains the higher compactness of [C14mim][BZ] aggregates than that of [C14mim][PO], observed by fluorimetry. The position of PO- and BZ- is in the stern and palisade layers of C14mim+ aggregates, respectively, located by 1H NMR. The existence of prolate ellipsoidal micelles for both SAILs has been established by small-angle neutron scattering measurements. Thus, the interfacial and bulk properties of [C14mim][PO] lie somewhere in between those of the SAILs having perfect aromatic counter-ions, [C14mim][BZ], and the SAILs having regular inorganic counter-ions like Cl-, Br-, etc.

Effects of tempering and heat strengthening on hardness, indentation fracture resistance, and wear of soda lime float glass

AbstractAnecdotal and empirical evidence suggests that heat strengthening treatments compromise the wear and scratch resistance of soda lime silicate (SLS) glass. This can be problematic when trying to clean inorganic debris from the glass surface which can result in scratches degrading the optical clarity of the glass surface. Interestingly, past work using a ball‐on‐flat tribometer showed that SLS has peculiar wear behaviors as a function of relative humidity (RH). In dry conditions, inorganic counter surfaces abrade SLS. In contrast, in high humidity conditions, SLS substrate exhibits wear resistance for a variety of inorganic counter‐surface materials. The focus of this fundamental study is to investigate the hardness, indentation fracture resistance (IFR), and wear resistance of SLS float glass with various thermal treatment histories—as‐received (exposed to ambient lab air for about a year), annealed, heat strengthened, and thermally tempered—as a function of humidity using Vickers indentation and ball‐on‐flat tribometer. Several hypotheses were considered, and it was proposed that Si‐O bond parameters, specifically strained bonds, may play an important role in the mechanochemical wear behavior of soda lime glasses at high humidity conditions.