J Colloid Interface Sci
September 2024
Hypothesis: The physical and mechanical properties of triacylglycerols (TAGs), or 'fats', depend on their composition and thermal history which, in turn, impact crystal structure and morphology. We examine whether thermal history can be mechanistically related to film removal by a surfactant solution.
Experiments: Model TAG mixtures, comprising triolein:tripalmitin:tristearin 0.
We investigate the structure and interactions of a model anionic/amphoteric mixed surfactant micellar system, namely, sodium dodecyl sulfate (SDS) and ,-dimethyldodecylamine -oxide (DDAO), employing SANS, FTIR, DLS, and pH measurements, in the range 0.1-100 mM total surfactant concentration and 0-100% DDAO. Increasing surfactant concentration is found to elongate the prolate ellipsoid micelles ( ∼ 25-40 Å), accompanied by up to a 6-fold increase in micellar charge.
View Article and Find Full Text PDFWe report the coupling of dynamic light scattering (DLS) in microfluidics, using a contact-free fibre-optic system, enabling the under-flow characterisation of a range of solutions, dispersions, and structured fluids. The system is evaluated and validated with model systems, specifically micellar and (dilute) polymer solutions, and colloidal dispersions of different radii (∼1-100 nm). A systematic method of flow-DLS analysis is examined as a function of flow velocity (0-16 cm s), and considerations of the relative contribution of 'transit' and 'Brownian' terms enable the identification of regions where (i) a quiescent approximation suffices, (ii) the flow-DLS framework holds, as well as (iii) where deviations are found, until eventually (iv) the convection dominates.
View Article and Find Full Text PDF