Volumetric properties of (N,N-dimethylformamide plus aliphatic diethers) at temperatures ranging from (298.15 to 358.15) K

Accurate density values of N,N-dimethylformamide (DMF) with diethyl ether (DEE), dipropyl ether (DPE), diisopropyl ether (DisoPE), dibutyl ether (DBE) or dipentyl ether (DPeE), were measured over the whole composition range at temperatures ranging from (298.15 to 358.15) K under atmospheric pressure by an Anton Paar densimeter. To gain some insight into the several aggregations of molecular interactions present in these mixtures, we calculated the excess molar volumes, V-E, of the mixtures from density data over the entire experimental conditions. The qualitative analysis of the excess molar volumes was made by taking into consideration of the molecular size of ethers and the nature of DMF. Negative excess volumes were observed in all these mixtures except for the high mole fraction of DMF in the system of DMF + DPeE at T= 298.15 K. It was found that the V-E values of these systems are increased with increasing the temperature. The experimental V-E data were correlated accurately with the Redlich-Kister type equation. (c) 2005 Elsevier Ltd. All rights reserved.