Structural interaction of novel dendrimer and subunits with water estimated with excess molar volumes, viscosities and free energies

Abstract

The 2,4,6-tridiethylmalonatetriazine (TDEMTA) dendrimer and subunits developed interaction potential when mixed with water due to structural reorientation. Thus excess volumes (V^E10^-6 m³ mol^-1), viscosities (η^E/0.1 N s m^-2) and molar free activation energy (ΔG^E  kJ mol^-1 K^–1) from 0.63 to 10 mm kg^-1 of 2,4,6-trichlorotriazine (TCT), 2,4,6-triacetotriazine (TAT), 2,4,6-trihydroxytriazine (THT) and 2,4,6-tridiethyl- malonatetriazine (TDEMTA) have been reported with water at 298.15 K. The V^E and η^E positive values inferred deviations from ideal behavior with an adequate potential to cause solute-solvent interactions. The ideally the V^E = 0 and η^E = 0, and their η^E0 noted as limiting excess viscosities were as TAT > 2,4,6-trihydroxytriazine (THT) = 2,4,6-trichlorotriazine (TCT) > 2,4,6-tridiethylmalonatetriazine (TDEMTA). The ΔG^E > 0, was higher by 15.15 kJ mol^-1 K^–1 with weaker interacting response of the dendrimer. The 3 x 10^-4 mm kg^-1 2,4,6-trihydroxytriazine (THT) showed higher ΔG^E values with an abrupt decrease with much disruption in molecular interaction similar to surfactant behavior. The lowest ΔG^E values were with the 2,4,6-trichlorotriazine (TCT) due to comparatively higher interactions of the chloride ion.

KEY WORDS: Excess viscosity, Trichlorotriazine, Hydrophilic, Hydrophobic, Hydrodynamic

Bull. Chem. Soc. Ethiop. 2011, 25(1), 119-126.