Volumetric and Viscometric Studies of Salicyl Amide, Salicylic Acid, and Acetyl Salicylic Acid in Alcohols at Different Temperatures

Abstract

Nonsteroidal anti-inflammatory drugs (NSAIDs) exhibit analgesic, anti-inflammatory, antipyretic and platelet inhibitory properties. Density and viscosity of salicyl amide, salicylic acid, and acetyl salicylic acid in water, methanol, and ethanol at T = (293.15 to 313.15) K have been measured in a molality range of (9.7·10−3 to 32.5·10−3) mol·kg−1 with the help of a commercially available vibrating-tube densimeter and viscometer. From the density data, apparent molar volume (Vϕ,1), partial molar volume (Vm∞), thermal expansion coefficient (α∞2), and (∂2Vm∞/∂T2) are calculated. The viscosity data are analyzed by the Jones−Dole equation to determine the values of the viscosity B-coefficient.