This study combines all-atom molecular dynamics simulations with small-angle neutron scattering to examine how surfactant oligomerisation reshapes non-ionic micelles. The work compares micelles formed by Triton X-100, a monomeric surfactant, with those formed by Tyloxapol, its oligomer, along with mixtures of the two. The central question is not how large or how spherical these aggregates are, but how they are organised internally, a property that conventional size-and-shape characterisation leaves largely unresolved.
The simulations and scattering data together show that oligomerisation reshapes mixed micelles well beyond changes in size and shape. Tyloxapol promotes water-filled internal cavities, creating polar pockets within a region normally treated as a dry hydrophobic core, and surfactant conformations become heterogeneous, with a broad range of chain arrangements coexisting inside a single micelle. The resulting mixed micelles adopt compact, oblate architectures rather than the simple spherical geometry often assumed in modelling. Together, these findings demonstrate that oligomer design offers a route to engineer the internal structure of soft nanomaterials, not just their outer dimensions. The paper was published in Small Science in 2026 by Ishkhanyan, Barlow, Lawrence, and Lorenz.