  We demonstrate that the formation of bicontinuous emulsions stabilized by
interfacial particles (bijels) is more robust when nanoparticles rather than
microparticles are used. Emulsification via spinodal demixing in the presence
of nearly neutrally wetting particles is induced by rapid heating. Using
confocal microscopy, we show that nanospheres allow successful bijel formation
at heating rates two orders of magnitude slower than is possible with
microspheres. In order to explain our results, we introduce the concept of
mechanical leeway i.e. nanoparticles benefit from a smaller driving force
towards disruptive curvature. Finally, we suggest that leeway mechanisms may
benefit any formulation in which challenges arise due to tight restrictions on
a pivotal parameter, but where the restrictions can be relaxed by rationally
changing the value of a more accessible parameter.
