Activation Of Viscous Flow Research Articles

Physicochemical analysis on molecular interactions in binary liquid mixtures at various temperatures and correlation with the Jouyban–Acree model (3-pentanol with allyl amine, allyl alcohol, and allyl chloride)

ABSTRACT This study investigates the molecular interactions in binary mixtures of 3-pentanol with three allyl compounds (allyl amine, allyl alcohol, and allyl chloride) at various temperatures. The excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy of activation of viscous flow were determined from measured values of densities, speeds of sound, and viscosities. The data were analysed to determine excess properties and deviations from ideal behaviour, highlighting the predominance of molecular interactions such as geometrical packing effects and free volume effects. The experimental results were correlated with the Jouyban−Acree model, which effectively relates the observed thermodynamic properties to the composition of the mixtures. This correlation allows for a deeper understanding of molecular interactions that influence the properties of these binary mixtures across different temperatures.

Investigation of intermolecular interactions in binary mixtures of N,N-dimethyl benzyl amine with higher alkanols (N,N-dimethyl benzyl amine with 1-octanol, 1-nonanol, 1-decanol)

ABSTRACT Measurements of densities (ρ), speeds of sound (u), and viscosities (η) for binary mixtures of N,N-dimethyl benzyl amine (DMBA) with 1-octanol (D1), 1-nonanol (D2), and 1-decanol (D3) were performed across temperatures from 303.15 K to 313.15 K under atmospheric pressure, covering all composition ranges. These experimental results were utilised to calculate the excess molar volume, excess isentropic compressibility, viscosity deviation, and the excess Gibbs free energy of activation for viscous flow. Calculations for partial molar properties and infinite dilution partial molar properties were also carried out for each binary mixture. The dominant intermolecular interactions within these mixtures were analysed using the PFP theory. Additionally, the Jouyban−Acree model was applied to predict the thermo physical properties such as density, speed of sound, and viscosity. The model’s accuracy was evaluated by comparing predicted values with experimental data through mean relative deviations (MRDs) and individual relative deviations (IRDs).

Thermodynamic and spectroscopic analyses of N-Methyl benzylamine-isomeric amyl alcohol binary mixtures: Jouyban-Acree model correlation and experimental validation

ABSTRACT Excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy of activation for viscous flow for binary mixtures of N-Methyl benzyl amine (NMBA) with 2-Methyl-2-butanol (2M2B), 2-Methyl-1-butanol (2M1B), and 3-Methyl-1-butanol (3M1B) were determined from measured densities (ρ), viscosities (η) and speeds of sound (u) at 303.15 K to 313.15 K. Influence Structural disparities on excess properties is discussed concerning intermolecular forces. The Prigogine – Flory – Patterson (PFP) theory identifies predominant molecular interactions, and the Jouyban – Acree model correlates density, speed of sound, and viscosity with composition. Thermodynamic activation parameters were calculated using the Eyring equation to study viscous flow thermodynamics. FT-IR and 1H NMR spectra of equimolar binary mixtures were analysed to confirm experimental findings through absorption bands (cm−1) and chemical shifts.

Investigation on Polyether Sulfone Toughening Epoxy Vitrimer: Curing and Dynamic Properties.

Diglycidyl ether of bisphenol A crosslinking with glutaric anhydride is used to form the conventional "covalent adaptive network", polyether sulfone (PES) by coiling and aggregating on the adaptive network is used to significantly increase the uncured resin viscosity for improving the processability of epoxy resin, but inevitably affecting the curing reaction and dynamic transesterification reaction. This study investigates the crucial roles of PES in curing dynamics and stress relaxation behavior. The results indicate that although PES does not directly participate in the crosslinking reaction of polyester-based epoxy vitrimers. Moreover, the isothermal curing studies reveal that the addition of PES can greatly bring forward the reaction rate peak from conversion α = 0.6 to α = 0.2, meaning that the curing mechanism transfers from chemical control to diffusion control. Dynamic property analysis shows that the addition of PES significantly accelerates stress relaxation, especially at lower temperatures, leading to low viscous flow activation energy Eτ and relatively insensitive stress relaxation behavior to temperature. Introducing PES into vitrimer resin greatly improves crosslinking density (2.31×10⁴molm- 3), enhancing glass transition temperature (82.68°C), tensile strength (68.66MPa), and fracture toughness (6.25%). Additionally, the modified vitrimer resin exhibits satisfying shape memory performance and reprocessing capability.

Excess Thermodynamic Properties and FTIR Studies of Binary Mixtures of Toluene with 2-Propanol or 2-Methyl-1-Propanol

Physical properties of the binary solutions, toluene with 2-propanol and 2-methyl-1-propanol, were measured at T = 293.15, 298.15, 303.15, 308.15, and 313.15 K and P = 100 kPa. The experimental density values were tested with the Emmerling et al. and Gonzalez-Olmos–Iglesias equations. The results indicate that the equation by Emmerling et al. is the best to correlate the density for toluene + 2-methyl-1-propanol system, while for toluene + 2-propanol, both proposed equations are proper to correlate the density with composition and temperature. The viscosity results were verified with different models containing two adjustable parameters. The values of viscosity deviation (∆η), excess molar volume (VE), excess Gibbs energy (ΔG*E), partial molar volumes (V1¯ and V2¯), and apparent molar volume (Vφ,1 and Vφ,2) were calculated. The values of the excess molar volume were positive for both systems, while negative values were obtained for the viscosity deviation and the excess Gibbs energy. The excess properties of the mixtures were adjusted to the Redlich–Kister equation. The values of thermodynamic functions of activation of viscous flow were computed and analyzed. Additionally, the Prigogine–Flory–Patterson (PFP) theory was applied to calculate VE and then compared with experimental values. The values of the percentage absolute average deviation obtained suggest the validity of this theory. The Fourier transform infrared spectroscopy (FTIR) spectra of the binary solutions studied in this work allowed for the understanding of the interactions between the molecules of these systems.

High-temperature structural drivers immobilizing alkaline substances in red mud-derived mineral wool

Smelting and fiberization of red mud (RM) is an attractive approach for rapid recovery of metal resources, production of mineral wool, and immobilization of hazardous alkalis. However, an enormous challenge remains in understanding alkali immobilization behavior in mineral wool over a broad A/S (Al2O3 to SiO2 mass ratio) range. Here we addressed the challenge through molecular dynamics, thermodynamic and experimental analyses. Increasing A/S ratio caused an increasing degree of structural order and the remarkable micro-phase separation occurred at A/S > 0.9. The role of Na+ and Ca2+ changed from the network-modifying cations to the charge-compensating cations. Melt viscosity decreased and then increased significantly with an intensified temperature sensitivity, identified by the increasing viscous flow activation energy from 211.5 to 377.03 kJ/mol in the temperature region from 1500 to 1570 °C. The transformation of thermodynamic properties (real mixed/excess molar Gibbs free energies, and entropy increment) corresponded to the structural changes. Thermal, mechanical and leaching tests confirmed the negative effect of this structural transformation on alkali immobilization. The A/S ratios controlled below 0.9 were proposed for environmental benefits and product stability. The investigation of immobilization mechanism provides valuable information for tuning the vitrification chemistry and developing safe and green mineral wool from RM.

Study on physicochemical properties of hydroxyl-functionalized ionic liquids

A thorough understanding of the physicochemical properties of ionic liquids (ILs) is significant for the design and synthesis of the desired ILs. In this study, three hydroxyl-functionalized ILs were designed and synthesized, and their density, viscosity, surface tension and refractive index were measured in the temperature range of 293.15–333.15 K, and it was found that they all decreased with the increase of temperature. By using the measured physicochemical property data and the corresponding empirical equations, the molecular volumes of the three ILs were calculated and the contribution of one (CH2-) group to the molecular volume was found to be 0.0262 nm3. The viscous flow activation properties were discussed and ΔH≠ > ΔS≠T was found for the three ILs, indicating that enthalpy effect is the main source of viscous flow resistance. Surface energy and surface entropy were calculated, and it was found that surface entropy is the main factor determining surface properties. The free volume was calculated, and it was found to increase with temperature, which could provide more space for light to pass through the medium, leading to a decrease in refractive index with temperature. Simultaneously, the influence of cation and anion structures on the properties of the ILs was also discussed.

Physico-chemical studies of non-aqueous binary liquid mixtures of N-methyl aniline with amino alcohols at various temperatures

ABSTRACT Densities (ρ), speeds of sound (u) and viscosities (η) for three binary mixtures of N-methyl aniline with amino alcohols (3-amino-propan-1-ol, 2-amino-2-methyl-propan-1-ol and 1-amino propan-2-ol) were measured at temperatures ranging from 303.15 to 313.15 K and at atmospheric pressure across the entire composition range. Excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy of activation of viscous flow were calculated using experimental data. Partial molar properties and infinite dilution molar partial properties were also determined for each binary system. The Prigogine-Flory-Patterson theory is used to identify the most important interaction. The results of the Jouyban-Acree model are discussed in terms of the mean relative deviation and individual relative deviation between the calculated and experimental densities, speed of sound, and viscosities as an accuracy criterion. FTIR studies have also been added to confirm the experimental findings of the investigated mixtures.

Thermo physical and spectroscopic properties of binary liquid mixtures at various temperatures and correlation with the Jouyban–Acree model (propargyl alcohol, ethanoic acid, propanoic acid and butanoic acid)

ABSTRACT A thorough investigation into binary mixtures of propargyl alcohol and various carboxylic acids (ethanoic, propanoic and butanoic) was conducted. Measurements of density (ρ), speed of sound (u) and viscosity (η) were meticulously performed across the entire range of mole fractions at temperatures (303.15 K−313.15 K) and atmospheric pressure (0.1 MPa). These data were used to calculate key thermodynamic and transport properties, including excess molar volume, excess isentropic compressibility, deviation in viscosity and excess Gibbs free energy of activation for viscous flow. The partial molar properties and infinite dilution molar partial properties were also determined for each binary system. Trends and behaviours were interpreted within the framework of intermolecular interactions, focusing on complex formation and specific chemical forces. The PFP theory and Jouyban–Acree model were critically applied, with confidence in the findings supported by FTIR studies.

Jouyban–Acree model assessment for physico-chemical properties of N,N-Dimethylbenzylamine with isomeric chlorobenzene systems

ABSTRACT Densities (ρ), speeds of sound (u), and viscosities (η) of binary mixtures of N,N-dimethyl benzyl amine (DMBA) with 1,2-dichlorobenzene (1,2-DCB), 1,3-dichlorobenzene (1,3-DCB), and 1,2,4-trichlorobenzene (1,2,4-TCB) were measured at temperatures ranging from 303.15 K to 313.15 K for selected compositions. Excess molar volume (V E ), excess isentropic compressibility (κ s E ), viscosity deviation (Δη), and excess Gibbs free energy for activation of viscous flow (ΔG *E ) were subsequently determined from the experimental data. The obtained results were analysed to elucidate the nature of intermolecular interactions, specifically focusing on attractive forces, steric hindrance or hetero-association within the mixtures. The Prigogine–Flory–Patterson (PFP) theory was employed to identify the dominant type of molecular interaction. The Jouyban–Acree model was applied to calculate densities, speeds of sound, and viscosities. The accuracy of the model was evaluated using mean relative deviations (MRDs) and individual relative deviations (IRDs) between the calculated and experimental values.

Effect of TiO2 on the structural properties and viscosity of CaO-SiO2-8.25 %MgO-15 %Al2O3-TiO2 slags

As a raw material for ironmaking, vanadium-bearing titanomagnetite will leads to an increase in the TiO2 content of blast-furnace slag and deteriorates the metallurgical properties of the slag. In this study, the effect of TiO2 content on the viscosity of CaO-SiO2–8.25 %MgO-15 %Al2O3-TiO2 slag system at fixed w(CaO)/w(SiO2) ratio of 1.2 was investigated, and Raman spectroscopy focusing on the relationship between the structure of high TiO2-bearing blast furnace slag and viscosity was performed. The findings showed that under the experimental condition, the viscosity of slag decreases with the increase of TiO2 content over a range of 20 to 35 %. The melting temperature of slag increases first and then decreases after w(TiO2) is higher than 30 %. The viscous-flow activation energy of slag decreases with the increase of TiO2 content, which has a concomitant variation corresponding with the results of the effect of TiO2 on viscosity. The analysis of Raman spectroscopy results reveals that the blast-furnace slag system is dominated by [SiO4]4- network structure. As the TiO2 content increases, more and more Ti4+ enters the silica-oxygen tetrahedral network structure, disrupting the Si-O-Si bond to form the [TiO4]4- structural unit and a small portion of the [TiO6]8- structural unit. The NBO/Si value of the Si4+ in the tetrahedron unit as an index for the degree of depolymerization of slags increased from 1.62 to 2.60 as the TiO2 content increased, the slag structure was gradually simplified and the slag viscosity was gradually decreased.

Eco-friendly material extrusion 3D printing for fabricating W-Ni-Fe lattices with improved compressive resistance

Tungsten (W) and its alloys are prevalently utilized in many special fields, such as the military and nuclear industry, owing to their exceptional attributes, including superior hardness, high density, and remarkable resistance to high temperatures. However, there are still challenges to achieve easy preparation of porous W alloys and uncover the secrets of their mechanical behavior. In this work, a porous lattice made from W93Ni4.9Fe2.1 with uniform microstructure was designed using enhanced material extrusion (MEX) 3D printing technology, offering exceptional formability while ensuring safety and environmental friendliness. The W93Ni4.9Fe2.1 lattice, fabricated at an extrusion temperature of 150 °C and infill percentage of 60 % exhibits the optimal geometry and homogeneous sintering shrinkage. The W93Ni4.9Fe2.1 lattice, fabricated at an extrusion temperature of 170 °C and infill percentage of 60 % shows the best compressive properties with the ultimate compressive strength of 1442 MPa and plastic strain of 19.8 %. The study of rheological properties of designed slurry determines the viscous flow activation energy of 1.64 kJ·mol−1 for the smooth extrusion of slurry, which is crucial for the formability of W93Ni4.9Fe2.1 lattice 3D printing. The ball milling treatment significantly improves the sinterability of W93Ni4.9Fe2.1 powder, confirming the effectiveness of mechanical alloying. This work presents a novel approach for fabricating complex structured porous W alloy with high-performance in a low-cost and environmentally friendly manner.

Reprocessable and repairable carbon fiber reinforced vitrimer composites based on thermoreversible dynamic covalent bonding

The emergence of vitrimers breaks through the limitation of traditional carbon fiber reinforced thermoset composites (CFRP) caused by their permanent crosslinking molecular networks. Herein, the dynamic cross-linked network of vitrimer was synthesized from Bisphenol A diglycidyl ether (DGEBA) and glutaric anhydride (GA) under the catalysis of zinc acetylacetonate (Zn(acac)2), and the corresponding carbon fiber reinforced vitrimer composites (CF/Vx) were prepared via an impregnation and hot pressing process. The dynamic covalent adaptable networks (CANs) of vitrimer endow CF/Vx with stress relaxation and creep characteristics. By adjusting the catalyst content, the dynamic performance of CF/V0.05 can be optimized to achieve the highest viscous flow activation energy (60 kJ/mol) and the lowest characteristic relaxation time (1.0 × 10−3 s). The unique dynamic properties enable CF/Vx with reprocessability at high temperature. Typically, the flexural modulus of CF/V0.05 decreased from 87 ± 1.81 GPa at room temperature to 4.62 ± 0.28 GPa at 220 °C, which confirms the feasibility of thermoplastic forming of CF/V0.05 at high temperatures. Based on this, a CF/V0.05-based cap-shaped component was successfully manufactured through a thermoforming process. Additionally, the CF/V0.05 composites also exhibit repairability for interlaminar fractures. The optimal CF/V0.05 can achieve a repair efficiency of 128 % under the hot press conditions of 180 °C, 10 MPa and 1 h. Hence, the reprocessable and repairable CF/Vx composites hold enormous potential in the engineering field.

Experimental and theoretical studies to investigate molecular interactions between ethylene glycol oligomers and 1-butyl-3-methylimidazolium bromide

The thermophysical characteristics of pure liquids and their mixes are substantial in applied as well as theoretical research. This paper presents the measured data on: density (ρ), viscosity (η), refractive index (nD) and consequent calculated parameters: {excess molar volume (VmE), partial molar volume (V¯m), excess partial molar volume (V¯mE), deviation in viscosity (Δη), excess Gibbs energy of activation of viscous flow (ΔG∗E), deviation in refractive index (ΔϕnD) and deviation in molar refraction (ΔxRM)} of binaries containing 1-butyl-3-methylimidazolium bromide ([BMIM]Br) with glycol oligomers (mono/di/tri/tetra-ethylene glycol) at T/K = 298.15–313.15 and pressure p/MPa = 0.1. The Redlich-Kister equation efficiently estimates the standard deviation between the experimental and calculated excess properties. The interactions between constituents were considered while interpreting the obtained results. The values of VmE, V¯mE, Δη, ΔϕnD and ΔxRM exhibited negative trends throughout the range, whereas ΔG∗E values displayed a sigmoidal shift (negative to positive) with increasing [BMIM]Br concentration. The VmE data has been explored in terms of Prigogine-Flory-Patterson (PFP) and Graph theories to elucidate the deviations in thermophysical properties of the mixtures caused by variations in strength and magnitude of interactions. Additionally, the η values were correlated using ten models and their correlation ability has been perceived via the average standard deviation percentage. The pure and binary mixtures were also spectroscopically examined using Fourier Transform InfraRed (FT-IR) and Raman spectroscopy to elucidate the structural variations.

Molecular interaction study using density, viscosity, speed of sound and FT-IR in 2-methyl-2-butanol + alkoxyethanols: Experimental and modelling approach

In this article, the intermolecular interactions in the binary liquid mixtures of 2-methyl-2-butanol with alkoxyethanols viz., 2-ethoxyethanol, 2-propoxyethanol and 2-butoxyethanol have been interpreted using thermophysical properties. Density (ρ), viscosity (η) and speed of sound (u) of pure components and their binary mixtures have been measured over the entire range of composition at 298.15, 303.15 and 308.15 K and at pressure p = 0.10 MPa. The experimental data were used to calculate the thermophysical properties such as excess molar volume (VmE), excess molar isentropic compressibility (Ks,mE), excess speed of sound (uE), deviation in viscosity (Δη) and excess Gibbs free energy of activation for viscous flow (ΔG∗E). The changes in these properties with composition and temperature of the liquid mixtures were discussed in terms of intermolecular interactions. Also, the effect of increase in alkyl chain length of alkoxyethanol molecule on these properties has been studied. The excess functions and their deviations have been correlated using Redlich-Kister type polynomial equation. The experimentally measured values of viscosities have been correlated with various semi-empirical relations such as Grunberg-Nissan, Tamura-Kurata, Hind et al., Katti-Chaudhri, McAllister’s two parameter model, Heric-Brewer and McAllister’s three parameter model. Apart from this, Prigogine-Flory-Patterson (PFP) theory has been used for the estimation of VmE values for studied binary mixtures. FT-IR spectra of these liquid mixtures have also been studied.

Study on the molecular interactions of binary mixtures of N-methyl benzyl amine with halo methane’s through thermodynamic properties and correlation with the Jouyban–Acree model

ABSTRACT The thermodynamic and transport properties of binary mixtures of N-methyl benzyl amine (NMBA) with halo methane compounds at temperatures from 303.15 K to 313.15 K were investigated. The study analysed the excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy for activation of viscous flow using measured densities (ρ), viscosities (η), and speeds of sound (u). The research also examined the impact of the inductive effect on excess properties concerning intermolecular attractive forces between the respective constituents. Furthermore, the Jouyban–Acree model was employed to correlate density, speed of sound, and viscosity with composition and obtained good agreement.

Exploring the effects of saccharides on the solvation behaviour of L-Citrulline in aqueous medium: Volumetric, transition state theory, transfer parameters and spectroscopic approach

This study examines the volumetric, viscometric and UV–vis characteristics of L-Citrulline in water and aqueous saccharides at atmospheric pressure across the whole concentration range and the absorber operating temperature range of 293.15 K -313.15 K. Density, partial molar volume, apparent molar isobaric expansion, Hepler's constant and hydration number were among the examined volumetric parameters, and viscosity coefficients, viscosity deviation and free energy for viscous flow activation were among the examined viscometric parameters. Stronger interactions between L-Citrulline and L-Arabinose were indicated by the increase in the transfer characteristics in the following order: L-Arabinose > D-xylose. A comparison of the taste behaviours of L-Citrulline in water and in an aqueous solution of saccharides has also been attempted. L-Citrulline interacts with all solvents in a significant way, as evidenced by the UV–visible spectra suggested by the shift in UV–visible absorption maxima that correspond with a rise in L-Citrulline content in the solvent systems chosen.

Study on the molecular interactions of some binary mixtures through thermodynamic properties and FT-IR spectra and correlation with the Jouyban–Acree model

ABSTRACT Densities (ρ), speeds of sound (u) and viscosities (η) were measured for three binary mixtures of propargyl alcohol with tetra chloromethane, trichloromethane, and dichloromethane from 303.15 K to 313.15 K at atmospheric pressure across the composition range. Excess molar volume, excess isentropic compressibility, deviation in viscosity, and excess Gibbs free energy of activation of viscous flow were calculated. Partial molar properties and infinite dilution molar partial properties were also determined for each system. Results suggest heteroassociates forming cross complexes and chemical forces with specific interactions. PFP theory was used to identify the predominant molecular interactions. The Jouyban–Acree model findings were discussed, considering mean relative deviation (MRDs) and individual relative deviation (IRD) between calculated and experimental data. FTIR studies were included to corroborate the experimental findings.

Influence of Complex Plasticizer on Plasticizing Effects and Rheological Properties of Plasticized Poly(Vinyl Alcohol)

AbstractPoly(vinyl alcohol) (PVA) was modified using D‐mannitol (DM) and 1‐butyl‐3‐methylimidazole bromide (BMIMBr) as the complex plasticizer (DB), and PVA/DB composite was prepared. The plasticizing effect of DB on PVA was studied by Fourier transform infrared spectroscopy (FT‐IR), differntial scanning calorimetry (DSC), thermos gravimetric analysis (TGA) and melt flow indexer (MI). FT‐IR analysis indicated that Br− of BMIMBr and OH of DM could form H‐bonds with OH of PVA. With the increase of DB, the melt temperature (Tm2) and crystallization temperature (Tc1) of PVA/DB composite decreased, the initial thermal decomposition temperatures (Td), thermal processing window (ΔT) and MI values increased respectively. Based on above studies, the influence of DB content on rheological properties of PVA/DB composite was investigated by the capillary rheometer. The result displayed that apparent viscosity of PVA/DB composite decreased with increasing DB content, shear rate and measured temperature. The non‐Newtonian index (n) increased and structural viscosity index (Δη) decreased with the increase of measured temperature and DB. The viscous flow activation energy (Eη) decreased as the shear rate and DB content increased. When the measured temperature, DB content and shear rate were in the range of Tm2+30 −Tm2+35 °C, 40–50 wt% and 764.8–1504.9 s−1, respectively, the spinnability of PVA/DB composite was optimal, which will lay a theoretical foundation for the exploration of melt spinning process in the future.

Thermo physical properties and IR spectral studies of some binary liquid mixtures and correlation with the Jouyban–Acree model

ABSTRACT Excess molar volume, excess isentropic compressibility, deviation in viscosity and excess Gibbs free energy for activation of viscous flow for binary mixtures of propargyl alcohol (J) with benzyl aldehyde (J1), benzylamine (J2) and benzyl alcohol (J3) components with selected compositions were determined from the measured values of densities (ρ), viscosities (η), and speeds of sound (u) of pure components and their mixtures from 303.15 K to 313.15 K. The effect of various functional groups on the excess properties has been discussed in terms of attractive forces between the components. The results of the Jouyban-Acree model are discussed in terms of the mean relative deviation and individual relative between the calculated and experimental densities, speed of sound, and viscosities as an accuracy criterion.FTIR studies have also been added to confirm the experimental findings of the investigated mixtures