RT Journal Article T1 Physico-chemical challenges on the self-assembly of natural and bio-based ingredients on hair surfaces: towards sustainable haircare formulations A1 Luengo, Gustavo S. A1 Leonforte, Fabien A1 Greaves, Andrew A1 González Rubio, Ramón A1 Guzmán Solís, Eduardo AB Polymers and surfactants are used in many technological and industrial applications such as the manufacture of functional materials and coatings, personal care and pharmaceutical products, food science, paints, anti-icing fluids, tertiary oil recovery and the paper industry. Polymer–surfactant mixtures are particularly important in shampoos and conditioners. However, as in almost every other industry over the past five or more decades, the performance of hair care formulations has been significantly improved by the use of petrochemical-derived ingredients. As a result, cosmetic formulations, and hair care formulations in particular, have been based primarily on polymers and surfactants that are neither renewable, nor derived from environmentally friendly processes, nor have a positive environmental impact. This contrasts with the extensive use of natural and renewable products, mainly plant extracts, in cosmetics in ancient times. Therefore, the substitution of currently used ingredients with others of natural origin has been a top priority for the cosmetic industry over the last two decades, and in order to achieve greater consumer acceptance, it is crucial to maintain and, where possible, improve the technical performance of such products. This paper describes the complexities and challenges of developing greener shampoo and conditioner ingredients and formulations to meet current and future needs, and outlines a methodological approach based on model hair surfaces and a selection of appropriate experimental and numerical techniques to achieve our goals. Some encouraging technical routes using biosurfactants, biopolymers and bio-based polymers are presented, along with the significant opportunity to obtain a wide range of green ingredients through molecular design and well-controlled biotechnological processes. Similar concerns apply to other cosmetic products such as waxes, fragrances, bleaching agents, etc. PB Royal Society of Chemistry SN 1463-9262 SN 1463-9270 YR 2023 FD 2023 LK https://hdl.handle.net/20.500.14352/105804 UL https://hdl.handle.net/20.500.14352/105804 LA eng NO G. S. Luengo, F. Leonforte, A. Greaves, R. G. Rubio and E. Guzman, Green Chem., 2023, 25, 7863-7882 DS Docta Complutense RD 6 oct 2024