Micron-Sized Silica-PNIPAM Core-Shell Microgels with Tunable Shell-To-Core Ratio

Abstract

Micron-sized hard core-soft shell hybrid microgels are promising model systems for studies of soft matter as they enable in-situ optical investigations and their structures/morphologies can be engineered with a great variety. Yet, protocols that yield micron-sized core-shell microgels with a tailorable shell-to-core size ratio are rarely available. In this work, we report on the one-pot synthesis protocol for micron-sized silica-poly(N-isopropylacrylamide) core-shell microgels that has excellent control over the shell-to-core ratio. Small-angle light scattering and microscopy of 2- and 3-dimensional assemblies of the synthesized microgels confirm that the produced microgels are monodisperse and suitable for optical investigation even at high packing fractions.

Compression of colloidal monolayers at liquid interfaces: in situ vs. ex situ investigation

“…We briefly verified that the transfer protocol affects the ex situ assemblies by drying CS microgel monolayers with overall hydrodynamic diameters ranging from approximately to 1000 nm 59 (5 mol% crosslinker density) with two different drying conditions; 'slow' drying at ambient conditions against open air, and 'fast' drying using a heat gun. Fig.…”

“…The detailed synthesis protocol for both silica nanoparticles and micron-sized silica-PNIPAM microgels can be found in. 59 In short, silica particles were synthesized via the well-known Sto ¨ber procedure. RITC dye was incorporated in the particles that were used for fluorescence microscopy experiments.…”

Volume Phase Transition of Thermoresponsive Microgels Scrutinized by Dynamic Light Scattering and Turbidity: Correlations Depend on Microgel Homogeneity

“…Contrarily, where we found the best agreement between the phase transition temperatures, that is the case for core–shell microgels and some of the “classical” PNIPAM microgels, we could calculate theoretical swelling curves based on the temperature-dependent attenuation using only two reference points for the hydrodynamic radius. We believe that such a correlation will be very helpful for future studies, for example on large microgels and core–shell microgels where the influence of gravitation might hamper the reliability of DLS measurements. In addition, attenuation measurements are fast, simple, do not require any data treatment other than background correction, and can be performed in parallel using temperature-controlled sample changers.…”

Core-softened colloid under extreme geometrical confinement

“…Moreover, the straightforward control over the characteristic length scales makes them excellent chemical building blocks for obtaining a wide variety of bottom-up self-assembled morphologies in nanostructured materials. [5][6][7][8][9][10] In this regard, it is noteworthy how confinement within narrow slits significantly alters the behavior of colloidal systems, introducing unique dynamics and properties. [11][12][13][14][15] In these constrained spaces, colloidal and solute particles experience restricted motion and altered interactions, 11,16,17 leading to distinctive phenomena compared to bulk systems.…”

“…Moreover, the straightforward control over the characteristic length scales makes them excellent chemical building blocks for obtaining a wide variety of bottom-up self-assembled morphologies in nanostructured materials. 5–10…”