The Influence of Thickeners on Shampoo Properties

The performance of shampoo is determined by complex interactions between surface active agents (SAAs), polymers, and formulation modifiers, which directly influence consumer-relevant properties. However, the formulation principles governing these interactions and their impact on product quality remain insufficiently characterized. Therefore, the aim of this study was to evaluate the formulation principles underlying the interaction between thickeners and surfactant systems in shampoo formulations and to assess how these interactions influence the overall performance and quality of the final product. For this purpose, two groups of shampoo formulations containing identical surfactant systems but different thickeners (acrylate copolymer and guar gum) were prepared and evaluated in terms of pH, cleansing power (wool thread method), foam volume and stability, and texture profile. The results demonstrated that pH values ranged from 6.52 to 7.23 in acrylate copolymer-based formulations and from 4.71 to 6.09 in guar gum-based formulations. Cleansing power reached up to approximately 35%, depending on surfactant composition and thickener type. Foam volume was higher in acrylate copolymer systems, with a maximum value of 161 mL, whereas guar gum-based formulations exhibited lower but more variable foam characteristics. Texture analysis revealed that guar gum formulations were more sensitive to changes in surfactant composition, whereas acrylate copolymer provided more consistent and controllable texture characteristics.