(44) Action of surfactants

               (43) Shampoo Fructis

             (45) Laundry Detergent Ariel

            (46) Dishwashing Liquid Quix

        Depending on their use, different household detergents possess distinct chemical composition; nevertheless, all major household cleaners contain surfactants.
 

        A surfactant is a substance that can greatly reduce the surface tension of water when used in low concentrations (37, 39). They are soluble surface-active agents comprised of a hydrophobic portion, usually a long alkyl chain that is attached to hydrophilic functional groups (38, 39). The hydrophilic end of the surfactant is strongly attracted to the water molecules, and the force of attraction between the hydrophobe and water is only slight. As a result, the surfactant molecules align themselves at the surface so that the hydrophilic end is towards the water, and the hydrophobe is squeezed away from the water. (37, 39). A surfactant can be classified by the presence of formally charged groups in its head. A nonionic surfactant has no charge groups in its head. The head of an ionic surfactant carries a net charge. If the charge is negative, the surfactant is more specifically called anionic; if the charge is positive, it is called cationic (39). Often a combination of surfactants is used to produce good grease cutting capability, soil suspension, and mildness in water of varying degrees of hardness (37,38).

       The shampoo Fructis is composed mainly of Sodium Lauryl Sulfate or SLS. SLS is a wetting agent, that allows the shampoo to spread easier and penetrate more profoundly. It is a cheap ingredient and mixed with Sodium Stearate, usually composes approximately fifty percent of a shampoo’s ingredients. About forty percent is water and the other 10 percent are preservatives, fragrance, and color (33, 34).



       The laundry detergent, Ariel, is composed mainly of Alkyl Ethoxylate Sulfate or AES. It is a relatively strong non-ionic emulsifier that has high water solubility (35, 36). It also reduces the surface tension of water thus allowing for the better elimination of greasy stains.



       The chilean dishwashing liquid, Quix, is composed mainly of Alkyl Polyglycoside and N,N'-bis(3-aminopropyl) Propane-1,3-Diamine. The first chemical is responsible for destroying bacteria when in contact with water, while the latter functions as a surfactant to remove grease stains and reduce water tension.