Parametric Study of Surfactant Effect on Mechanical and Dissolution Properties of Detergent Tablets

The aim of this study os to investigate the functional characteristics (mechanical strength and disintegration time) of effervescent detergent tablets containing chlorine provider in the presence of surfactant. A preliminary study high-lighted that the presence of 2% of sodiumdodecyl sulfate (SDS) was not favorable to the tablet mechanical properties, inducing a lower "bonding ability, whereas the disintegration time and the end-dissolution time led us to consider just the disintegration time to express the behavior of the tablets in water. A parametric study has been completed to assess the influence of the mixing method, the nature, the hydrophilic-lipophilic balance, the granulometry, and the cçoncentration of the surfactant on the tablet properties. In all cases, surfactant presented adverse effects on the mechanical properties and had a retarding effect on disintegration time, but neither solubility, hydrophilic-lipophilic balance, interfacial properties, nor ionic character could be clearly involved to explain surfactant contribution. Furthermore, tablet dissolution could not be correlated to surfactant available surface, as evidenced by granulometry comparison on one side and concentration impact on the other side (a similar effect was observed from 1 to 15%). On the contrary, mechanical properties were dramaged as much as the area developed by surfactant particles increased. On the basis of this work, it has been concluded that SDS interacts with the other compounds of the formula by creating weak interparticle bond and limiting water uptake responsable for disintegratio