Volumetric Behaviour Ofn-Methylformamide-(C1-C10)alkan-1-Ol Andn,n-Dimethylformamide-(C1-C10)alkan-1-Ol Solvent Systems

Abstract

Densities were measured for the N-methylformamide-(C 1 -C 10 )alkan-1-ol and N,N-dimethylformamide-(C 1 -C 10 )alkan-1-ol solvent mixtures at 298·15 K over the whole miscibility range (0 < X 1 < 1). The excess volumes (V E ), which are discussed in terms of intermolecular interactions, are negative for the mixtures with the smallest alkanols in the series and increase with increase in the chain length. Comparison with other amide-alcohol mixtures previously investigated (formamide and pyrrolidin-2-one) indicates that the excess volumes are strongly influenced by the size of the alcohol and to a lesser extent by the nature of the amide. In contrast with the amide-water system, neither the amide size nor its degree of sustitution plays an important role in the amide-alcohol systems investigated.

Viscosity and surface tension of binary systems of N,N-dimethylformamide with alkan-1-ols at different temperatures

“…The viscosity deviations Dg for all binary systems investigated at T = 298.15 K are negative over the entire mole fraction range as shown in figure. 1, which agree with the results reported by García et al [10]. The negative values of viscosity deviations Dg are noticed in systems with different molecular size where dispersion forces or weak dipole-dipole forces are dominant [30][31][32].…”

“…Also, the viscosities of DMF with propanol binary mixtures at temperatures ranging from 303.15 K to 323.15 K were measured by Saleh and Uddin [9]. Values of viscosity were also obtained by García et al [10] for binary mixtures of DMF with n-alkanols (C 1 -C 10 ) at T = 298.15 K. To the best of our knowledge, no surface tension data were reported previously for DMF with higher alkanols at different temperatures [1].…”

The N-methylpyrrolidone–(C1–C10) alkan-1-ols solvent systemsElectronic Supplementary Information (ESI) available: Properties of pure components, densities, viscosities and refractive indices of mixtures NMP(1) + alkan-1-ols(2) at 298.15 K (Tables S1–S4). See http://www.rsc.org/suppdata/cp/b1/b109709c/

“…2 For decades, the challenge of the petroleum industry has been to find selective solvents with good ability for phase separation in extractive distillations; NMP, with a high boiling point (475 K) and relaxation characterized by only one Debyetype spectral component, 3 represents quite a simple model for rigid, non-associating polar species (dipole moment m 30 C ¼ 4.09 D); due to its ability to modify the potential reactivity of reacting states in electron and proton transfer reactions, NMP is also widely used in settings such as solventreactivity relationships. [4][5][6][7][8][9][10][11] Alkanols are polar liquids, strongly self-associated by hydrogen bonding to extents of polymerization that may differ depending on temperature, chain length, and position of the OH group. Although some authors suggest self-association in terms of monomer-dimer equilibria, 12,13 others propose that dimers and higher oligomers are also important in dilute solutions; 14 pure methanol may exist mainly as a cyclic dimer, with contributions ranging from open dimers to trimers, whereas ethanol may exist mainly as a trimer complex species.…”

N,N-DIMETHYLFORMAMIDE (CAS No. 68-12-2)

“…3 Na Tabela 1, são mostradas algumas propriedades do DMF. 1,6,7 Propriedades Fórmula molecular 1 C 3 H 7 NO Massa molar 1 …”

“…Viscosidade 6 0,80 cP Decomposição térmica < 350°C  amônia, óxidos de carbono e aminas > 350°C  óxidos de nitrogênio, dimetilamina e CO 2 Em estudos realizados para determinar as principais impurezas presentes na N,Ndimetilformamida, foi observada a presença de água advinda dos reagentes empregados na produção deste solvente. A água presente pode causar hidrólise parcial do DMF (Esquema 1) levando à formação de dimetilamina e ácido fórmico, e também de pequena quantidade de formiato de dimetilamina.…”