“…Very long-term stability of microbubble populations is rare because film desorption and wrinkling effects due to fluid bulk viscoelasticity will generally take place [22,26]. However, we believe this effect is minimized in the case of microbubbles coated with MYVATEX/PEG40S and similar mixtures that we have observed in the past [16,20] because the condensed monolayer coating is nearly "solid," i.e., gel-like, and with extremely low monomer solubility in the water phase [27]. Based upon these arguments, we would expect that the most stable microbubble population of the emulsifiers tried here will be formed in the solution containing long chains capable of obtaining low surface tension, high elastic modulus, and solid-like behavior, i.e., MYVATEX/PEG40S.…”