Vapor-liquid equilibrium,excess gibbs energy and excess enthalpy of 1, 3 dioxolane-methylcyclohexane at t = 313.15 k

Data on vapor-liquid equilibrium and enthalpy of mixing H^E are, obtained for the mixture 1, 3 dioxolane-methylcyclohexane at 313.15 K (40.0°C). Correlation of the data is given by using Redlich-Kister expressions and the excess functions G^E = RT(X₁ In γ₁ + X₂ In γ₂) and TS^E = H^E - G^E are thereby calculated. A comparison is made between this mixture and those formed by 1, 3 dioxolane with cyclohexanol and cyclohexanone.     

The Softness Parameters of Ions. Prediction of the Occurrence of Miscibility Gaps in Molten Salt Mixtures

Softness parameters σ_M for cations and σ_X for anions, have been calculated as dimensionless quantities for approx. 90 cations and 18 anions. They are given by σ_M = [σ_A (M^m+) - σ_A(H⁺)]/σ_A(H⁺) and σ_X = [σ_B(X^a?) - σ_B(OH^?)]/σ_A(H⁺) where σ_A = [σI_i(M) + ΔH⁰_h(M^m+)]/m and σ_B = [-E_a(X) + ΔH⁰_h(X^a?)]/a are Ahrland's parameters. The new normalized and comparative (to the test ions H⁺ and OH^?) softness parameters are positive for soft ions and negative for hard ones. These parameters, obtained independently, are used with a four-coefficient equation to calculate coordinate bond energies for metal halides with acceptable accuracy. Considerations of the average coordination in reciprocal molten salt mixture lead to an expression for the metathesis energy change as proportional to the product of the differences in softness parameters of the two cations and the two anions. An empirical one-coefficient equation involving the softness parameters is proposed to deal with next-nearest-neighbor interactions in binary common-ion molten salt mixtures. These relationships are then used with Blander and Topol's equation to predict the occurrence of irascibility gaps in uni-univalent reciprocal salt mixtures. The gaps found in other systems are also discussed in terms of the softness of the constituent ions.     

Generation and Electron-Transfer Reactivity of the Long-Lived Photoexcited State of a Manganese(IV)-Oxo-Scandium Nitrate Complex

Photoexcitation of a manganese(IV)-oxo-scandium nitrate complex ([(Bn-TPEN)Mn^IV(O)]²⁺−Sc(NO₃)₃) in a solvent mixture of trifluoroethanol and acetonitrile (v/v=1 : 1) resulted in generation of the long-lived photoexcited state, which is detected by nanosecond laser transient absorption measurements. The transient absorption maximum (λ_max) of the ²E excited state of [(Bn-TPEN)Mn^IV(O)]²⁺−Sc(NO₃)₃ is observed at 620 nm with lifetimes of 7.1 μs. The λ_max value is blue-shifted and the lifetime becomes longer as compared with the previously reported values of λ_max (640 nm) and lifetime (6.4 μs) of the ²E excited state of the 1 : 2 complex between [(Bn-TPEN)Mn^IV(O)]²⁺ and Sc(OTf)₃ ([(Bn-TPEN)Mn^IV(O)]²⁺−(Sc(OTf)₃)₂). The electron-transfer reactivity of the ²E excited states of [(Bn-TPEN)Mn^IV(O)]²⁺−Sc(NO₃)₃ was similar to that of [(Bn-TPEN)Mn^IV(O)]²⁺−(Sc(OTf)₃)₂. The long lifetime and the high reactivity of the ²E excited state of [(Bn-TPEN)Mn^IV(O)]²⁺−Sc(NO₃)₃ provide an excellent photooxidant for oxidation of compounds, which would otherwise be impossible to be oxidized.     

Synthesis and characterization of styrene–acrylic ester copolymers

Homopolymers and copolymers of styrene and different acrylic esters (i.e., acrylates) were synthesized by the free‐radical solution polymerization technique. Feed ratios of the monomers styrene and cyclohexyl acrylate/benzyl acrylate were 90 : 10, 75 : 25, 60 : 40, 50 : 50, 40 : 60 and 20 : 80 (v/v) in the synthesis of copolymers. All 6 homopolymerizations of acrylic ester synthesis were carried out in N,N(dimethyl formamide) except for the synthesis of poly(cyclohexyl acrylate) (PCA), where the medium was 1,4‐dioxane. Benzoyl peroxide (BPO) and azobisisobutyronitrile (AIBN) were used as initiators. The polymers synthesized were characterized by FTIR, ¹H‐NMR, ¹³C‐NMR spectroscopy, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and viscosity measurements. The reactivity ratios were determined by the Fineman–Ross method using ¹H‐NMR spectroscopic data. The reactivity ratios (r) for the copolymerization of styrene (r_S) with cyclohexyl acrylate (r_CA) were found to be r_S = 0.930 and r_CA = 0.771, while for the copolymerization of styrene with benzyl acrylate, the ratios were found to be r_S = 0.755 and r_BA = 0.104, respectively. The activation energies of decomposition (E_a) and glass‐transition temperature (T_g) for various homo‐ and copolymers were evaluated using TGA and DSC analysis. The activation parameters of the viscous flow, voluminosity (V_E) and shape factor (ν) were also computed for all systems using viscosity data. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 79: 1513–1524, 2001     

Modelling the temperature dependence of kinematic viscosity for refined canola oil

Viscosities of refined, bleached, deodorized (RBD) and refined, bleached, winterized (RBW) canola oils were measured at temperatures from 4 to 100°C. The viscosities of these refined canola oils were exponentially related to the oil temperature. Viscosity of the RBW oil was slightly greater than that of the RBD oil when the temperature was below 15°C. Compared to refined soybean oil, the canola oils were substantially more viscous. The viscosity of canola oil was modelled asv = exp(C₀ + C₁T + C₂T²). The maximum predicted error was less than 1.6% over the tested temperature range.     

乙酸乙酯-1,2-丙二醇二元系的密度、折射率和黏度

常压下测定了乙酸乙酯和1,2-丙二醇二元系在298.15～323.15 K下的密度、折射率和黏度,建立了混合液密度、黏度随组成和温度变化关系的方程。计算了过量摩尔体积V^E,折射率偏差Δn_D,黏度偏差Δη和过量流动活化自由能ΔG^*E。结果表明,过量摩尔体积低温时在全浓度范围内为负值,但随温度升高,在富酯区变为正值;而折射率偏差高温时在富醇区为微小正值,其他情况都是负值;黏度偏差和过量流动活化自由能显示了相同的变化关系,均为负值,且都随温度降低而偏差增大。     

Photoinitiated Reactions of H Atoms with CO2: OH(v = 0) Rotational Excitation from the 239-nm Photolysis of CO2HI Complexes

Photoinitiated H + CO₂ → OH + CO reactions are discussed, with emphasis on reactions in CO₂HI complexes. Under single-collision bulk conditions, reaction probability rises with collision energy by two orders of magnitude throughout the range 10300–19000 cm⁻¹ (ΔH = 8960 cm⁻¹). Modest probabilities at collision energies well above threshold are interpreted as due to the inability of the heavier nuclei to move fast enough to trap the H atom on the HOCO potential surface. The pronounced increase in reaction probability with collision energy can be due to impact-induced distortion of the CO₂ frame, localizing the H atom in a shallow region of the HOCO potential surface long enough for the heavier nuclei to move toward the HOCO equilibrium geometry, thus capturing the H atom. Measurements of nascent OH(v = 0) R, T excitations indicate a significant bias toward product translation and away from OH rotation at the highest collision energies. OH LIF spectra taken at different collision energies provide a map of nascent OH(v = 0) rotational excitation for different values of E^†, the HOCO^† energy in excess of the OH + CO product channel. With CO₂HI complexes, pairwise I-H and H-CO₂ repulsions before HOCO^† is formed increase the I-HOCO^† speed at the expense of HOCO^† internal excitation. It is pointed out that with CO₂HBr, the Br atom is 3.6 Å from the C atom along a line perpendicular to the CO₂ axis, with the H atom localized near one of the O atoms. CO₂HI is expected to be qualitatively similar. The OH(v = 0) rotational distribution obtained using 239-nm photolysis of CO₂HI complexes differs markedly from that obtained under single-collision conditions at the same photolysis wavelength, the former being colder and qualitatively distinct from any of the OH(v = 0) distributions obtained at a single collision energy. The OH(v = 0) rotational distribution obtained using CO₂HI complexes can be reconciled with a bimodal P(E^†) distribution (e.g., ∼ 30% at E^† ∼ 800 cm⁻¹ and ∼ 70% at E^† ∼ 6000 cm⁻¹). The 6000-cm⁻¹ component is attributed to the squeezed-atom effect (E^† = 7880 cm⁻¹ for single-collision conditions at the same photolysis wavelength), while the origin of the other component is uncertain. It may derive from (i) mechanisms that produce HOCO^† with low E^† values, (ii) mechanisms that relax HOCO^† and/or OH such as interactions with the nearby I atom and (iii) higher-than-binary complexes.     

Structural interactions of globular proteins—Bovine serum albumin,egg albumin,and lysozyme,in aqueous medium,elucidated with molar volumes,viscosities, energy functions,and IR spectra from 293.15 to 303.15 K

Densities (ρ), apparent molar volumes (V_?), viscosities (η), and IR spectra on 0.0010–0.0018% aqueous solutions of bovine serum albumin (BSA), egg albumin (E‐Alb), and lysozyme at an interval of 0.0004% and at temperatures from 293.15, 298.15, and 303.15 K have obtained. The free energy (ΔG), entropy (ΔS), and enthalpy (ΔH) data with compositions and temperatures are calculated from the values of the flow velocity (v_f) of viscous flow, which decrease with temperature. The densities decrease with concentrations and temperatures except BSA, and the V_? values slightly increase with concentrations for BSA and lysozyme, which depict structural reorientations and transition states of protein molecules with increase in viscosities and decrease in reduce viscosities. The reduce viscosities at 293.15 K for BSA, E‐Alb, and lysozyme are noted positive, and for BSA and lysozyme remain positive at 298.15 and 303.15 K, whereas for E‐Alb it is negative. Activation energies (E*) for lysozyme remain almost constant, and are higher than those of the BSA and E‐Alb, respectively, also slightly higher E* values for the BSA than those of the E‐Alb at 293.15 and 298.15, and lower than of the E‐Alb at 303.15 K, are observed elucidating greater structural interactions for BSA at lower while weaker at temperatures. Stretching frequencies of amide (? NHCO? ), ? NH? , ? CO, and ? CH? groups of proteins are noted from IR spectra with broader stretching frequencies for ? NH? . © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 1420–1429, 2007     

Use of a dynamic mechanical analyzer to study supported polymers

The real and imaginary parts of the complex modulus of polymers which must be supported can be determined with the Du Pont Dynamic Mechanical Analyzer. Polymer coatings of equal thickness are laminated on both sides of a thin metal sheet. The flexural modulus of the laminate is given by E = E₁X³ + E₂(1 ? x³) where E₁ and E₂ are the moduli of the metal and the polymer, respectively, and x is the thickness fraction of metal. Under some conditions, the dynamic viscosity of the polymer can also be determined.     

Thermodynamic properties of methanol–benzene mixtures at elevated temperatures

The total pressure and the compositions of the vapour and liquid phases of the methanol–benzene system have been determined under equilibrium conditions at 100°, 120°, 140°, 160°, 180°, 200° and 220° for ten levels of concentration. The corresponding activity coefficients of methanol and benzene are reported; their values indicate that the equilibrium data are thermodynamically consistent. An azeotrope is found at all temperatures, its methanol content increasing as the temperature is increased. The relationship log P_az = 6·5098—(1,766/T) expresses the interdependence of the azeotrope vapour pressure P_az(lb/in² abs.) and temperature T(°K). Estimates of integral heat of mixing (H^E) and entropy change due to mixing (S^E) as functions of liquid composition (x_meth) have been made from the excess free energy of mixing G^E,(T) x_meth functions. Both H^E and S^E at a given x are positive increasing functions of temperature. These phenomena are discussed in terms of the dissociation of methanol ‘polymer’ and the formation of benzene–methanol ‘complexes’.     

Reaction kinetics modeling and thermal properties of epoxy–amines as measured by modulated‐temperature DSC. I. Linear step‐growth polymerization of DGEBA + aniline

A mechanistic approach including both reactive and nonreactive complexes can successfully simulate both nonreversing (NR) heat flow and heat capacity (C_p) signals from modulated‐temperature DSC in isothermal and nonisothermal reaction conditions for different mixtures of diglycidyl ether of bisphenol A + aniline. The reaction of the primary amine with an epoxy–amine complex initiates cure (E_1A1 = 80 kJ mol^?1), whereas the reactions of the primary amine (E_1OH = 48 kJ mol^?1) and secondary amine (E_2OH = 48 kJ mol^?1) with an epoxy–hydroxyl complex are rate determining from about 2% epoxy conversion on. The reliability of the proposed mechanistic model was verified by experimental concentration profiles from Raman spectroscopy. When cure temperatures are chosen inside or below the full cure glass‐transition region, vitrification takes place partially or completely, respectively, as can be concluded from the magnitude of the stepwise decrease in C_p. The effect of the epoxy conversion (x) and mixture composition on thermal properties such as the glass‐transition temperature (T_g), the change in heat capacity at T_g [ΔC_p(T_g)], and the width of the glass transition region (ΔT_g) are considered. The Couchman relationship, in which only T_g and ΔC_p(T_g) of both the unreacted and the fully reacted systems are needed, was evaluated to predict the T_g– x relation by using simulated concentration profiles. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 91:2798–2813, 2004     

Density, ultrasonic velocity, viscosity and their excess parameters of the binary mixtures of N,N-dimethylaniline+1-alkanols (C3-C5), +2-alkanols (C3-C4), +2-methyl-1-propanol, +2-methyl-2-propanol at 303.15K

The density, ultrasonic velocity of sound and viscosity of binary mixtures of N,N-dimethyl aniline (N,NDMA) with 1-propanol, +2-propanol, +1-butanol, +2-butanol, +1-pentanol, +2-methyl-1-propanol, +2-methyl-2-propanol were measured at 303.15 K. These experimental data have been used to calculate excess volume V ^E , excess ultrasonic speeds u ^E , excess intermolecular free length L _f ^E , excess acoustic impedance Z ^E , excess isentropic compressibility κ _s ^E , deviation in viscosity Δη and excess Gibbs free energy of activation of viscous flow (G* ^E ). The values of L _f ^E and κ _s ^E are negative over the wide range of composition for all the binary mixtures, while the values of Z ^E are positive. These results have been used to discuss the nature of interaction between unlike molecules in terms of hydrogen bonding, dipole-dipole interaction, proton-acceptor interaction and dispersive forces. The viscosity data have been correlated using three equations: Grunberg and Nissan, Katti & Chaudhri and Hind et al. The excess/deviations were fitted by a Redlich-Kister equation and the results were analyzed in terms of specific interactions present in these mixtures.     

Polymers based on N,N‐diglycidylaniline. I. Investigations of the curing kinetics by dynamic differential scanning calorimetry measurements

N,N‐Diglycidylaniline was reacted with aniline (yielding polymer EP‐1) and the newly synthesized chromophore 4‐(phenylazo)aniline (yielding polymer EP‐2). The curing kinetics of these two epoxy resin systems was studied in dynamic experiments by means of differential scanning calorimetry. Kinetic parameters such as the activation energy and frequency factor were estimated with the Ozawa method [E(O) and A(O), respectively], the Kissinger method [E(K) and A(K), respectively], and the modified Avrami method [E(A) and A(A), respectively]. The activation energy and frequency factor of EP‐1 were much lower than those of EP‐2 estimated with the Ozawa, Kissinger, and Avrami methods. The activation energy and frequency factor for EP‐1 determined with the Ozawa method [E(O) = 55.8 kJ/mol, A(O) = 10 × 10³ 1/s] and the Avrami method [E(A) = 56.4 kJ/mol, A(A) = 9.2 × 10³ 1/s] were higher than those determined with the Kissinger method [E(K) = 51.0 kJ/mol, A(K) = 2 × 10³ 1/s]. In the case of EP‐2, the kinetic parameters calculated with the Ozawa model [E(O) = 140.4 kJ/mol, A(O) = 12.3 × 10¹³ 1/s] and the Kissinger model [E(K) = 139.9 kJ/mol, A(K) = 10.9 × 10¹³ 1/s] were higher than those calculated with the Avrami model [E(A) = 130.4 kJ/mol, A(A) = 7.9 × 10¹² 1/s]. The obtained polymers were characterized with Fourier transform infrared, ¹H‐NMR, differential scanning calorimetry, and ultraviolet–visible spectroscopy. The polymers exhibited low glass‐transition temperatures in the range of 57–79°C and good solubility in common organic solvents. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Unusual Elastic and Mechanical Behaviors of Copper Phosphate Glasses with Different Copper Valence States

Elastic and mechanical properties such as Young's modulus E, Poisson's ratio ν, Debye temperature θ_D, Vickers hardness H_v, fracture toughness K_c, and fracture surface energies γ_f of yCuO_x·(100−y)P₂O₅ glasses (y= 45, 50, 55) with different copper valence states, i.e., R(Cu⁺) = Cu⁺/(Cu⁺+ Cu²⁺), at room temperature (humidity 64%) have been examined. The following features have been found: (1) the glass transition temperature (218–434°C), H_v (2.7–4.4 GPa), E (50.6–78.2 GPa), and θ_D (358–434 K) decrease largely with increasing R(Cu⁺); (2) the mean atomic volume, K_c (0.56–1.14 MPa·m^1/2), and γ_f (1.9–11.2 J·m⁻²) tend to increase with increasing R(Cu⁺); (3) 50CuO_x·50P₂O₅ glasses with R(Cu⁺) = 0.42 and 0.55 have a high resistance against crack formation in Vickers indentation tests and no crack is observed in the 45CuO_x·55P₂O₅ glass with R(Cu⁺) = 0.57 under an applied load of about 98 N. The results demonstrate that elastic and mechanical properties of yCuO_x·(100−y)P₂O₅ glasses depend strongly on the copper valence state and the CuO_x/P₂O₅ ratio. The unusal mechanical and elastic properties of copper phosphate glasses are well explained qualitatively by considering unique oxygen coordination and bonding states of Cu⁺ ions, i.e., lower coordination number and more covalent bonding compared with Cu²⁺ ions.     

Stereocomplex formation between poly(L‐lactic acid) and poly(D‐lactic acid) with disproportionately low and high molecular weights from the melt

Poly(L ‐lactic acid) (PLLA) and poly(D ‐lactic acid) (PDLA) with very different weight‐average molecular weights (M_w) of 4.0 × 10³ and 7.0 × 10⁵ g mol^?1 (M_w(PDLA)/M_w(PLLA) = 175) were blended at different PDLA weight ratios (X_D = PDLA weight/blend weight) and their crystallization from the melt was investigated. The presence of low molecular weight PLLA facilitated the stereocomplexation and thereby lowered the cold crystallization temperature (T_cc) for non‐isothermal crystallization during heating and elevated the radial growth rate of spherulites (G) for isothermal crystallization, irrespective of X_D. The orientation of lamellae in the spherulites was higher for the neat PLLA, PDLA and an equimolar blend than for the non‐equimolar blends. It was found that the orientation of lamellae in the blends was maintained by the stereocomplex (SC) crystallites. Although the G values are expected to decrease with an increase in X_D or the content of high‐molecular‐weight PDLA with lower chain mobility compared with that of low‐molecular‐weight PLLA, G was highest at X_D = 0.5 where the maximum amount of SC crystallites was formed and the G values were very similar for X_D = 0.4 and X_D = 0.6 with the same enantiomeric excess. This means that the effect of SC crystallites overwhelmed that of chain mobility. The nucleating mechanisms of SC crystallites were identical for X_D = 0.1–0.5 in the T_c range 130–180 °C. Copyright © 2011 Society of Chemical Industry     

Volumetric,ultrasonic and viscometric studies of binary liquid mixures of N-ethylaniline + chlorobenzene, + Bromobeneze, + 1, 2-dichlorobenzene + 1, 3-dichlorobenzene+1, 2, 4-trichlorobenzene at 303.15 and 308.15K

We measured densities (ρ), ultrasonic speeds (u) and viscosities (η) for binary binary mixtures of N-ethylaniline (N-EA) with chlorobenzene (CB), bromobenzene (BB), 1,2-dichlorobenzene (1,2-DCB), 1,3-dichlorobenzene (1,3-DCB), and 1,2,4-trichlorobenzene (1,2,4-TCB) and their pure liquids at 303.15 K and 308.15 K. These experimental data were used to calculate the excess volume (V ^E ), deviations in ultrasonic speeds (Δu), deviation in isentropic compressibility (Δ κ _s ), deviation in intermolecular free length (ΔL _f ), deviation in acoustic impedance (ΔZ), deviation in viscosity (Δη) and excess Gibbs free energy of activation of viscous flow (G* ^E ). The variations of these properties with composition of binary mixtures suggest loss of dipolar association, difference in size and shape of the component molecules, dipole-dipole interactions and hydrogen bonding between unlike molecules. The viscosity data were correlated with Grunberg and Nissan, Katti and Chaudhri, and Hind et al. equations and the results were compared with the experimental results. The excess parameters were fitted to the Redlich-Kister polynomial equation using multi parametric nonlinear regression analysis to derive the binary coefficients and to estimate the standard deviation.     

Density,refractive index,excess molar volumes and deviations in molar refraction at 298.15 K for binary and ternary mixtures of DIPE (OR TAME) + 1‐methanol (or 1‐propanol) + trihexyltetra‐decylphosphonium bis (2,4,4‐trimethylpentyl) phosphinate

The excess molar volumes (V^E) and the deviations in molar refraction (ΔR) at 298.15 K were determined for the binary systems {diisopropyl ether (DIPE) + 1‐propanol}, {Tert‐amyl methyl ether (TAME) + methanol}, {DIPE + trihexyltetradecylphosphonium bis(2,4,4‐trimethylpentyl)phosphinate ([P_666,14][TMPP])}, {TAME + [P_666,14][TMPP]}, {methanol + [P_666,14][TMPP]} and {1‐propanol + [P_666,14][TMPP]} using a digital vibrating‐tube densimeter and a precision digital refractometer. The V^E and ΔR were correlated with the Redlich–Kister equation for binary systems. In addition, the ternary V^E and ΔR data at 298.15 K were predicted for the ternary systems {DIPE + 1‐propanol + [P_666,14][TMPP]} and {TAME + methanol + [P_666,14][TMPP]} by using the binary contribution model of Radojkovi? with correlated sub‐binary Redlich–Kister parameters. © 2011 Canadian Society for Chemical Engineering     

Similarity Solutions for the Population Balance Equation Describing Particle Fragmentation

Similarity solutions are obtained to the population balance equation describing particulate systems undergoing fragmentation. The solutions are restricted only by the requirement that the breakage rate of particles of volume v be of the form φ(v) = Av^b and the breakage distribution function of the form ω(u, v) = ?(v/u)/u, where u is the volume of the fragmenting particle. Under such conditions, the moments of the distribution asymptotically approach the form N_i(t) α t ^(1?i)/b , and the particle size distribution function is shown to obey a first-order linear ordinary integro-diflerential equation.

For the case ?(v/u) = γ(v/u)^γ?2, analytical solutions to the above equation were obtained. Complete solutions as well as asymptotic behavior are given. The results are potentially applicable to a wide range of particle fragmentation problems, including char/ash fragmentation during pulverized coal combustion, explosively generated aerosol formation, ore comminution, powder crushing and grinding, floe breakage, and crystallization kinetics.     

Investigation into the phase formation in the ZrO<Subscript>2</Subscript>-CeO<Subscript>2</Subscript> system

Nanopowders of solid solutions with different compositions are prepared in the zirconia-enriched region of the ZrO₂-CeO₂ system. The crystallization of these powders and the formation of the monoclinic, cubic, and tetragonal solid solutions of the composition (Zr_{1 – x} Ce_x)O₂ are investigated. It is found that the unit cell parameters of the solid solutions increase as the cerium content increases. This confirms the fact that cerium ions [r(Ce⁴⁺) = 1.11 ] substitute for zirconium ions [r(Zr⁴⁺) = 0.98 ] in these solid solutions. The average size of crystallites of the solid solutions under investigation increases from 5 to 60 nm in the temperature range 500–1200°C.Original Russian Text Copyright © 2005 by Fizika i Khimiya Stekla, Panova, Glushkova, Nefedova.     

Excess molar volumes and molar enthalpies in the binary mixtures of {x1CH3CHClCH2Cl+x2CH3(CH2)n?1OH} (n=1 to 4) at T=298.15K

The excess molar volumes V _m ^E and excess molar enthalpies H _m ^E at T=298.15 K and atmospheric pressure for the binary systems {x₁CH₃CHClCH₂Cl+x₂CH₃(CH₂) _n−1OH} (n=1 to 4) have been determined from density measurements by using a digital vibrating-tube densimeter and an isothermal calorimeter with flow-mixing cell, respectively. The 1-alkanols are methanol, ethanol, 1-propanol and 1-butanol. The V _m ^E values of the binary mixtures increase with chain length of the 1-alkanols, resulting in entire negative V _m ^E values for methanol, ‘S-shaped’ for ethanol, being nega- tive at low and positive at high mole fraction of 1,2-dichloropropane, and entire positive V _m ^E values for both 1-propanol and 1- butanol. The H _m ^E values for all systems show an endothermic effect (positive values), which exhibits a regular increase in magnitude when the number of -CH₂- group in 1-alkanols is progressively increased and maximum values of H _m ^E varying from 741 J·mol⁻¹ (methanol) to 1,249 J·mol⁻¹ (1-butanol) around x₁=0.63−0.72. The experimental results of both H _m ^E and V _m ^E were fitted to Redlich-Kister equation to correlate the composition dependence. The experimental H _m ^E data were also used to test the suitability of the Wilson, NRTL, and UNIQUAC models. The correlation of excess enthalpy data in these binary systems using UNIQUAC model provides the most appropriate results except for the system containing methanol.