Bulletin of the Chemical Society of Ethiopia (Apr 2011)
<b>Structural interaction of novel dendrimer and subunits with water estimated with excess molar volumes, viscosities and free energies</b>
Abstract
The 2,4,6-tridiethylmalonatetriazine (TDEMTA) dendrimer and subunits developed interaction potential when mixed with water due to structural reorientation. Thus excess volumes (VE10-6 m3 mol-1), viscosities (ηE/0.1 N s m-2) and molar free activation energy (ΔGE 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 VE and ηE positive values inferred deviations from ideal behavior with an adequate potential to cause solute-solvent interactions. The ideally the VE = 0 and ηE = 0, and their ηE0 noted as limiting excess viscosities were as TAT > 2,4,6-trihydroxytriazine (THT) = 2,4,6-trichlorotriazine (TCT) > 2,4,6-tridiethylmalonatetriazine (TDEMTA). The ΔGE > 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 ΔGE values with an abrupt decrease with much disruption in molecular interaction similar to surfactant behavior. The lowest ΔGE values were with the 2,4,6-trichlorotriazine (TCT) due to comparatively higher interactions of the chloride ion.
