Vogel-Fulcher-Tammann Equation Research Articles

Development, dielectric response and functionality of SrTiO3/epoxy nanocomposites

Composite systems of epoxy resin and SrTiO3 nanoparticles have been prepared and studied in different filler concentrations. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) revealed that there was a successful filler integration and fine dispersion in the polymer matrix. Moreover, Broadband dielectric spectroscopy (BDS) was employed for the determination of the dielectric response of all manufactured systems. Dielectric results divulge three relaxation processes which are referred to: (a) glass to rubber transition of the polymer matrix (α-mode), (b) re-arrangement of polar side groups of the polymer matrix (β-mode) and (c) interfacial polarization between systems’ components. It was found that all nanodielectric systems exhibit enhanced dielectric properties which are mainly attributed to the semiconductive nanoinclusions and to the extended interface between the polymer matrix and the nanofiller. Finally, dynamic analysis of the relaxation processes was also performed. Vogel–Fulcher–Tammann equation describes the α-mode’s loss peak dependence on temperature, whereas the β-mode follows the Arrhenius expression. In case of β-mode it was found that the presence of the nanoinclusions hinders the orientation of the matrix’s polar side groups.

Superionic Conduction over a Wide Temperature Range in a Metal–Organic Framework Impregnated with Ionic Liquids

AbstractMost molecules in confined spaces show markedly different behaviors from those in the bulk. Large pores are composed of two regions: an interface region in which liquids interact with the pore surface, and a core region in which liquids behave as bulk. The realization of a highly mobile ionic liquid (IL) in a mesoporous metal–organic framework (MOF) is now reported. The hybrid shows a high room‐temperature conductivity (4.4×10−3 S cm−1) and low activation energy (0.20 eV); both not only are among the best values reported for IL‐incorporated MOFs but also are classified as a superionic conductor. The conductivity reaches over 10−2 S cm−1 above 343 K and follows the Vogel–Fulcher–Tammann equation up to ca. 400 K. In particular, the hybrid is advantageous at low temperatures (<263 K), where the ionic conduction is superior to that of bulk IL, making it useful as solid‐state electrolytes for electrochemical devices operating over a wide temperature range.

Viscosities and Conductivities of Binary Mixtures of 4‐(Diethoxyphosphoryl)butyl Triphenylphosphonium Hexafluorophosphate with Organic Solvents

AbstractIn this work, a phosphonate‐functionalized ionic liquid, 4‐(diethoxyphosphoryl)butyl triphenylphosphonium hexafluorophosphate (PFIL) has been synthesized and characterized by FTIR, NMR and HRMS spectra. The viscosities (η) and conductivities (κ) of three binary mixtures of PFIL with acetonitrile (ACN), N,N‐dimethylformamide (DMF), and dimethyl sulfoxide (DMSO), respectively, were investigated in the temperature range from 293.15 to 343.15 K at atmospheric pressure. Solid PFIL dissolves in all these polar solvents within the concentrations studied (mole fraction of PFIL from 0.01 to 0.14). The experimental studies indicate that the viscosities of the three binary mixtures decrease in the following order: [PFIL(1) + DMSO(2)] > [PFIL(1) + DMF(2)] > [PFIL(1) + ACN(2)], while as expected, the conductivities increase in the following order: [PFIL(1) + ACN(2)]>[PFIL(1) + DMF(2)]>[PFIL(1) + DMSO(2)]. The conductivities as a function of temperature have been well correlated by Vogel‐Fulcher‐Tammann (VFT) and Arrhenius equations, while viscosities can be better fitted by using VFT equation. The dependence of conductivity on concentration for the studied systems is well represented by Casteel‐Amis equation.

Viscosity, Electrical Conductivity, Density and Surface Tension of Methyltriphenylphosphonium Carboxylate Ionic Liquids

Abstract In this paper, three new kinds of phosphonium-based room temperature ionic liquids (ILs) [Ph3PCH3][CH3(CH2)8COO] (MTPP-D), [Ph3PCH3][CH3(CH2)10COO] (MTPP-L), and [Ph3PCH3][CH3(CH2)12COO] (MTPP-M) were synthesized using triphenylphosphine, dimethyl carbonate and carboxylic acids as raw materials. The viscosity, electrical conductivity, density and surface tension of the synthesized ILs were measured in the temperature range from 298.15 K to 333.15 K under ambient pressure. Meanwhile, the effects of temperature and alkyl chain length on their viscosity, electrical conductivity, density and surface tension were also investigated. The molecular volume, standard entropy, lattice energy and isobaric expansivity of the three ILs were calculated at 298.15 K. Experimental results indicate that the viscosity, density and surface tension of the three ILs decrease significantly with the increase of temperature, while the electrical conductivity shows an opposite trend. The longer the alkyl chain, the higher the viscosity, the lower the electrical conductivity, density and surface tension of the ILs. The experimental dynamic viscosity can be well correlated by the Vogel-Fulcher-Tammann (VFT) equation and simple linear equation. The temperature dependence of electrical conductivity can be well fitted by Arrhenius equation and VFT equation. The molecular volume, standard entropy and isobaric expansivity increase with increasing alkyl chain length, while the lattice energy decreases.

In Situ Thermodielectric Analysis of the Gelatinization Mechanism of Raw Maize Starch: An Experimental and Theoretical Approach

Raw maize starch, initially stored at ambient temperature and relative humidity, was examined by means of Broadband Dielectric Spectroscopy in the temperature range from 30 to 130 °C and in the frequency range from 0.1 Hz to 1 MHz. The α-relaxation processes of amylose and amylopectin were, for the first time, separately recorded and analyzed by employing the electric modulus formalism, while the gelatinization mechanism is discussed and modeled. Molecular dynamics analysis, conducted via the Vogel–Fulcher–Tammann equation, and the Debye and Cole–Cole dielectric function models were employed to further understand the gelatinization process and the dielectric behavior of amylose and amylopectin respectively. In addition, the transformation of V-amylose to free amylose was also observed and discussed.

Conductivity of N-(2-methoxyethyl)-substituted morpholinium- and piperidinium-based ionic liquids and their acetonitrile solutions

N-ethyl-N-(2-methoxyethyl)-morpholinium bis(trifluoromethylsulfonyl)imide [Et(MEO)Mor][TFSI], N,N-bis(2-methoxyethyl)-morpholinium bis(trifluoromethylsulfonyl)imide [Bis(MEO)Mor][TFSI] and N,N-bis(2-methoxyethyl)-piperidinium bis(trifluoromethylsulfonyl)imide [Bis(MEO)Pip][TFSI] room-temperature ionic liquids (RTILs) were synthesized and their electrochemical properties were studied. Three stages of synthesis of RTILs were used, including the alkylation of secondary and tertiary amines and the anion exchange. The structure of RTILs was confirmed by1H, [Formula: see text]C, H,H-COSY,1H–[Formula: see text]C correlation spectroscopy NMR and XPS. Three main approaches based on the Arrhenius, Litovitz, and Vogel–Fulcher–Tammann equations were used to analyze the ion transport properties of RTILs. In addition, the electrical conductivity of the binary acetonitrile solutions of RTILs was studied. It was found that the activation energy and conductivity of RTILs depended on their polarity and ability to associate which affects the mobility of charge carriers and viscosity of the system.

Density, Viscosity, and Speed of Sound of Pure and Binary Mixtures of Ionic Liquids Based on Sulfonium and Imidazolium Cations and Bis(trifluoromethylsulfonyl)imide Anion with 1-Propanol

We present densities, viscosities, and speed of sound of pure and binary mixtures of three ionic liquids, triethylsulfonium bis(trifluoromethylsulfonyl)imide, [Et3S][TFSI], 1-allyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [Amim][TFSI], and 1,3-dihydroxyimidazolium bis(trifluoromethylsulfonyl)imide, [(OH)2Im][TFSI], with 1-propanol from (293.15 to 343.15) K at 0.1 MPa. We also include densities, viscosities, and speed of sound of pure ionic liquid 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide for validation. Densities and speed of sound are measured using a vibrating tube densimeter while viscosities are from a pellet microviscometer. The density and viscosity of pure ionic liquids are correlated by means of the Gardas and Coutinho and Vogel–Tammann–Fulcher equations, respectively. From the speed of sound measurements, we obtain isentropic compressibility, speed of sound deviation, and isentropic compressibility deviation for mixtures of ionic liquids and 1- propanol. Excess molar volumes and viscosity deviations are calculated from the experimental data. The excess molar volumes for the binary mixtures with [Et3S][TFSI] and [Amim][TFSI] present positive and negative deviations from ideality while those for the binary mixture with [(OH)2Im][TFSI] exhibit only negative deviations. Viscosity deviations for [Et3S][TFSI] + 1-propanol, [Amim][TFSI] + 1-propanol, and [(OH)2Im][TFSI] + 1-propanol are negative over the entire temperature range. The speed of sound deviations are positive and negative for the binary mixtures of 1-propanol with [Et3S][TFSI] and [Amim][TFSI], whereas those for the mixture with [(OH)2Im][TFSI] are negative.

Diglycidyl ether of bisphenol A/chitosan‐graft‐polyaniline composites with electromagnetic interference shielding properties: Synthesis, characterization, and curing kinetics

Conducting filler based on chitosan and grafted polyaniline (Ch‐g‐PANI) was prepared with different grafting ratios and used as fillers for polyester powder coating system. Differential scanning calorimetry is applied to study the effect of Ch‐g‐PANI on the curing of the polyester powder coating. The activation energy calculated by isoconversional Kissinger method was increased by either increasing the Ch‐g‐PANI content or the content of polyaniline in the filler, suggesting the contribution of the filler in the curing reactions. The cured samples were characterized using FTIR and TG analyses. Thermogravimetric analysis showed that the total thermal stability was enhanced upon the filler addition as detected from the values of integral procedural decomposition temperature. Furthermore, a dielectric study showed that the dielectric constant and loss were increased upon increasing of the filler. Vogel–Fulcher–Tammann equation was well‐fitted when used to examine the dependence of α‐relaxation on the temperature and the dielectrically calculated Tg values were comparable to that measured by DSC. The shielding effectiveness toward microwaves was enhanced by increasing the filler content. POLYM. ENG. SCI., 59:372–381, 2019. © 2018 Society of Plastics Engineers

CORRELACIÓN DE VISCOSIDADES PARA MEZCLAS DE BIOCOMBUSTIBLES

Correlation represents the relation between the variation of viscosity (η) of pure and binary chemical systems of 1-alcohols and n-alkanes with temperature and pressure, number of carbon atoms and variable concentrations. Representative gasoline hydrocarbons: iso-octane gasoline, cyclohexane, 1-hexene and pseudocumene, and alcohols: 1-butanol and 2-butanol, were used in this study. Binary mixtures were: 1-hexene + 1-butanol, cyclohexane + 1-butanol, iso-octane + 1-butanol, iso-octane + 2-butanol, pseudocumene + 1-butanol, and pseudocumene + 2-butanol. Experimental data of viscosity η were correlated with Vogel-Fulcher-Tammann equation (VFT), combined with Tait's equation. Prediction was performed using the Dymond-Assael rigid spheres model (RHS), with a modification to the model and with Eyring Theory supported by mixing laws.

The Temperature Effect on the Transport Properties of 1-Alkyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide Ionic Liquids

The temperature dependences of specific and equivalent conductivities, viscosity, density, and crystallization temperature are determined for three 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide ([C n MeIm] [Tf2N], n = 2, 3, 4) ionic liquids saturated with water vapor at room temperature. It is established that in the area of positive temperatures, the relationship between viscosity and conductivity obeys the fractional Walden rule with exponents of 0.97, 0.92, and 0.92 for ionic liquids with ethyl-, propyl-, butylradicals, respectively. The temperature dependences of conductivity and viscosity are approximated using the Vogel–Fulcher–Tammann equation (R2 > 0.999), and ideal glass transition temperatures T0 are calculated for the investigated liquids. The obtained values of T0 depend largely on the chosen range of temperatures. It is shown that [C2MeIm][Tf2N] occupies a separate position with regard to [C3MeIm][Tf2N] and [C4MeIm][Tf2N].

Temperature Dependence on Density, Viscosity, and Electrical Conductivity of Ionic Liquid 1-Ethyl-3-Methylimidazolium Fluoride

Ionic liquids are considered environmentally friendly media for various industrial applications. Basic data on physicochemical properties are significant for a new material, in terms of developing its potential applications. In this work, 1-ethyl-3-methylimidazolium fluoride ([EMIm]F) ionic liquid was synthesized via an anion metathesis process. Physical properties including the density, viscosity, electrical conductivity, and thermal stability of the product were measured. The results show that the density of [EMIm]F decreases linearly with temperature increases, while dynamic viscosity decreases rapidly below 320 K and the temperature dependence of electrical conductivity is in accordance with the VFT (Vogel–Fulcher–Tammann) equation. The temperature dependence of the density, conductivity, and viscosity of [EMIm]F can be expressed via the following equations: ρ = 1.516 − 1.22 × 10−3 T, σm = 4417.1exp[−953.17/(T − 166.65)] and η = 2.07 × 10−7exp(−5.39 × 104/T), respectively. [EMIm]F exhibited no clear melting point. However, its glass transition point and decomposition temperature are −71.3 °C and 135 °C, respectively.

Measurement and Correlation of High-Pressure Densities and Atmospheric Viscosities of Ionic Liquids: 1-Butyl-1-methylpyrrolidinium Bis(trifluoromethylsulfonyl)imide), 1-Allyl-3-methylimidazolium Bis(trifluoromethylsulfonyl)imide, 1-Ethyl-3-methylimidazolium Tetracyanoborate, and 1-Hexyl-3-methylimidazolium Tetracyanoborate

Four ionic liquids, [bmpyr][Tf2N] (1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide), [amim][Tf2N] (1-allyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide), [emim][TCB] (1-ethyl-3-methylimidazolium tetracyanoborate), and [hmim][TCB] (1-hexyl-3-methylimidazolium tetracyanoborate), were studied. High-pressure densities were measured at pressures up to 200 MPa and at temperatures of 312−433 K. Densities and viscosities at atmospheric pressure were measured over a temperature range of 293 to 373 K, and average relative deviation (ARD) of correlation with Vogel–Fulcher–Tammann equation for viscosity were within 0.08%. Correlation of the density data with the Tait equation could be obtained to within 0.02% ARD. Isobaric expansivities calculated from the Tait equation were constant or decreased slightly with increasing temperature in accordance with trends commonly reported for ionic liquids. Parameters for the e*-modified Sanchez–Lacombe equation of state are tabulated that allow correlati...

Dielectric relaxation studies in super-cooled liquid and glassy phases of anti-cancerous alkaloid: Brucine

Brucine has good anti-tumor effects, on both liver cancer and breast cancer. It has bioavailability of 40.83%. Since the bioavailability of the drug is low, an alternative method to increase its bioavailability and solubility is by changing the drug into glassy form. We used Differential Scanning Calorimetry (DSC) for studying the glass forming ability of the drug. Brucine was found to be a very good glass former glass transition temperature 365 K. Based on the DSC analysis we have used broadband dielectric spectroscopy (BDS) for studying the drug in the super cooled and glassy state. BDS is an effective tool to probe the molecular dynamics in the super cooled and glassy state. Molecular mobility is found to be present even in the glassy state of this active pharmaceutical ingredient (API) which is responsible for the instability. Our aim is to study the factors responsible for instability of this API in amorphous form. Cooling curves for dielectric permittivity and dielectric loss revealed the presence of structural (α) and secondary relaxations (β and γ). Temperature dependence of relaxation time is fitted by Vogel–Fulcher–Tammann equation and found the values of activation energy of the α relaxation, fragility and glass transition temperature. Paluch’s anti correlation is also verified, that the width of the α-loss peak at or near the glass transition temperature Tg is strongly anticorrelated with the polarity of the molecule. The larger the dielectric relaxation strength Δe (Tg) of the system, the narrower is the α-loss peak (higher value of βKWW).

Calorimetric study on Ge23Se67Sb10–0.5CsCl glass

The mechanical behavior of Ge23Se67Sb10 glass can be improved by adding CsCl facilitating the nano-crystaline formation. Understanding the crystallization mechanism of chalcogenide glass can help in directing the subsequent annealing processing and tuning the microstructure and physical properties. In this work, 99.5Ge23Se67Sb10–0.5CsCl glass was prepared and its transformation kinetics was investigated under non-isothermal conditions with heating rate up to 400 K min−1. Using Vogel–Fulcher–Tammann equation, the ideal glass transition temperature was determined as T 0g = 434.1 K. Using the classical JMA theory, the average activation energy and average growth exponent were determined as 135.0 and 2.4 kJ mol−1, while using the model considering impingements (MCI), the two parameters were determined as 120.9 and 3.2 kJ mol−1, respectively. Compared to JMA theory, the MCI model can fit the transition curves better, and it shows that the growth mode of the present glass is between two-dimension and three-dimension. By comparing with the result of Ge23Se67Sb10 glass, it is found that addition of CsCl can reduce the growth dimension and activation energy during crystallization.

Insight into the dynamics of low temperature dielectric relaxation of ordinary perovskite ferroelectrics

The temperature dependence of the dielectric response of ordinary ferroelectric materials exhibits a frequency-independent anomalous peak as a manifestation of the ferroelectric to paraelectric phase transition. A second anomaly in the permittivity has been reported in different ferroelectric perovskite-type systems at low temperatures, often at cryogenic temperatures. This anomaly manifests as a frequency-dependent local maximum, which exhibits similar characteristics to that observed in relaxor ferroelectrics around their phase transition. The origin of this unexpected behavior is still controversial. In order to clarify this phenomenon, a model-free route solution is developed in this work. Our findings reveal the same critical linear pattern/glass-like freezing behavior previously observed for glass-forming systems. Contrary to current thought, our results suggest that a critical-like dynamic parameterization could provide a more appropriate solution than the conventional Vogel–Fulcher–Tammann equation. The implemented methodology may open a new pathway for analyzing relaxation phenomena in other functional materials like relaxor ferroics.

Effects of polydispersity on the glass transition dynamics of aqueous suspensions of soft spherical colloidal particles

Thermoresponsive poly(N-isopropylacrylamide) (PNIPAM) particles of a nearly constant swelling ratio and with polydispersity indices (PDIs) varying over a wide range (7.4% - 48.9%) are synthesized to study the effects of polydispersity on the dynamics of suspensions of soft PNIPAM colloidal particles. The PNIPAM particles are characterized using dynamic light scattering (DLS) and scanning electron microscopy (SEM). The zero shear viscosity ($\eta_{0}$) data of these colloidal suspensions, estimated from rheometric experiments as a function of the effective volume fraction $\phi_{eff}$ of the suspensions, increases with increase in $\phi_{eff}$ and shows a dramatic increase at $\phi_{eff}=\phi_{0}$. The data for $\eta_{0}$ as a function of $\phi_{eff}$ fits well to the Vogel-Fulcher-Tammann (VFT) equation. It is observed that increasing PDIs results in increasingly fragile supercooled liquid-like behavior, with the parameter $\phi_{0}$, extracted from the fits to the VFT equation, shifting towards higher $\phi_{eff}$. The observed increase in fragility is attributed to the prevalence of dynamical heterogeneities (DHs) in these polydisperse suspensions, while the simultaneous shift in $\phi_{0}$ is ascribed to the decoupling of the dynamics of the smallest and largest particles. Finally, it is observed that the intrinsic nonlinearity of these suspensions, estimated at the third harmonic near $\phi_{0}$ in Fourier transform oscillatory rheological experiments, increases with increase in PDIs. Our results are in agreement with theoretical predictions and simulation results for polydisperse hard sphere colloidal glasses and clearly demonstrate that jammed suspensions of polydisperse colloidal particles can be effectively fluidized with increasing PDIs.

Dielectric relaxation and carrier transport in epoxy resin and its microcomposite

Epoxy resin and its microcomposite are widely used as electrical insulation in electrical equipment. Surface flashover and breakdown properties of these materials can be influenced by dielectric relaxation process and charge carrier behavior. The charge transport characteristics and dielectric relaxation process for neat EP and its microcomposites were studied by means of dielectric relaxation spectroscopy. The glass transition temperatures Tg of the two kinds of samples were investigated with differential scanning calorimetry measurement, which were approximately 105 °C and 120 °C, respectively. Both the two kinds of samples were sputtered with gold electrodes on two sides, and electrodes' diameter was 30 mm. The properties of dielectric relaxation was measured by Concept 80 Novocontrol broadband dielectric spectrometer at various temperatures from 100 °C to 180 °C. There is a relaxation peak which labeled α in the range of high frequencies on account of the molecular chain movement or motion of segmental chains when the temperature is above Tg. At the same time, the dc conductivity attributed by the charge carrier transport occurs in the range of low frequencies. Besides, there are different relaxation times for molecular chains with different length scales. Moreover, there is a broad distribution of relaxation time for both neat EP and its microcomposites and the relaxation time distribution at different temperatures was calculated. In addition, it was found that the relation between peak frequency of relaxation process and temperature follow the Vogel-Fulcher-Tammann (VFT) law, and temperature dependences of dc conductivity also obey the VFT equation. The Vogel temperatures of dielectric relaxation process and charge carrier transport were calculated by fitting the results of permittivity and conductivity. The glass transition temperatures for neat EP and its microcomposite were estimated to be 102 °C and 117 °C through Vogel temperatures, which are in consistence with DSC measurement results. It represents that free volume in the two kinds of samples increases with the increase of temperature, thus enhancing molecular chain movement and charge carrier transport process.

Electrical properties of epoxy-glue/(Bi12MnO20–BiMn2O5) composite

Electrical properties of composite consisted of epoxy-glue and powdered bismuth manganite Bi12MnO20–BiMn2O5 ceramics were studied. Samples contained 66 wt% of bismuth manganite. Secondary electron images and backscattered electron images were collected for the epoxy-glue and the epoxy-glue/bismuth manganite samples. Microanalysis shown that majority of bismuth manganite powder was homogenously distributed in epoxy-glue matrix. Lack of changes in crystallographic structure, in 300–450 K range, was deduced from the X-ray diffraction patterns. The electric impedance was measured at radio-frequencies. It was analysed using electric permittivity ɛ*( T, f ) and modulus M″(T, f ) representation. Epoxy-glue/bismuth manganite composite exhibited, at room temperature, conductivity, σ( f ) = 10−5 to 10−7 S m−1, permittivity, ɛ′≈10, losses, tan δ = 0.2–0.8 and dispersion markedly lower than bismuth manganite ceramics. Electric relaxation was induced in epoxy-glue/bismuth manganite composite samples. The Vogel–Fulcher–Tammann equation was fitted to relaxation times temperature dependence, obtained from M″(T, f ). The estimated values of Vogel–Fulcher equation parameters were frequency f0 = 2.2 × 108 Hz, energy UT = 1050 K and glass transition temperature Tg = 282 K. The relaxation times were attributed to strains, which would occur at interfacial layers between the bismuth manganite grain and the polymer matrix.

Electric Double Layer Dynamics in Poly(ethylene oxide) LiClO4 on Graphene Transistors

Formation of an electric double layer (EDL) is a powerful approach for exploring the electronic properties of two-dimensional (2D) materials because of the ultrahigh capacitance and induced charge in the 2D materials. In this work, epitaxial graphene Hall bar devices are gated with an EDL using a 1 μm thick solid polymer electrolyte, poly(ethylene oxide) and LiClO4. In addition to carrier density and mobility, ion dynamics associated with the formation and dissipation of the EDL are measured as a function of temperature over a gate bias range of ±2 V. The room temperature EDL formation time (∼1–100 s) is longer than the dissipation time (∼10 ms). The EDL dissipation is modeled by a stretched exponential decay, and the temperature-dependent dissipation times are described by the Vogel–Fulcher–Tammann equation, reflecting the coupling between polymer and ion mobility. At low temperatures, approaching the glass transition temperature of the electrolyte, the dissipation times of both cations and anions exceed...

Glass viscosity at crystallization temperature: an approach

In this work glasses which crystallize by surface or volume were selected and produced with the aim of studying the behavior of their viscosities at the crystallization temperature, using the equation proposed by Vogel–Fulcher–Tammann (VFT). The viscosity curves, determined from the VFT equation, included some modifications in the equation parameters. However, the characteristic temperatures such as half-sphere, glass transition, dilatometric softening and melting were always used. The temperatures corresponding to these phenomena were determined by dilatometric analysis (optic and contact dilatometry) and differential thermal analysis, which were used to determine the crystallization temperature of the glasses. From the analysis of the obtained experimental viscosity curves and the ones found in the literature for the studied compositions among other glasses, which show the same mechanisms of crystallization, it was found that there is a standard behavior of the parent glasses regarding their viscosities in the crystallization temperature. These viscosities are shown to be near to 104.28 ± 0.41 Pa s for surface crystallization and 106.37 ± 0.51 Pa s for volume crystallization.