Optimizing Amino Acid Surfactant Formulations: A Systematic Approach

Amino acid surfactants (AAS) have emerged as environmentally friendly alternatives to traditional petroleum-based surfactants. In the consumer industry, formulators are rapidly adopting AAS to replace Sodium Lauryl Ether Sulfate (SLES) in response to market trends and shifting consumer behavior. However, AAS cannot simply replace SLES due to challenges in achieving the desired viscosity, as they do not respond well to salts like sodium chloride (NaCl) and are sensitive to pH changes.

Recent studies suggest that formulating at the pKa of AAS and adding nonionic co-surfactants (such as fatty alcohols and fatty acids) can help overcome these challenges. Despite this, there remains a need for a comprehensive understanding and systematic approach to determine the factors that influence the viscosity of AAS-based formulations across various applications.

In this research, we systematically study the effects of various nonionic dialkyl and dialkene amides as additives in AAS-based formulations. We focus on the impact of structural factors, including double bonds, branching, and chain length, on the viscosity response of AAS-based formulations. This study includes the different responses of several AAS, such as sodium lauroyl sarcosinate, sodium cocoyl glutamate, and sodium cocoyl methyl taurate, to these nonionic additives.

These findings highlight the critical role of structural factors in understanding the viscosity responses of AAS-based formulations. Our research provides formulators with practical guidelines for future product development, ensuring that their formulations meet desired performance parameters.