Preparation of poly(lactic-acid)-particle stabilized liquid marble and the improvement of its stability by uniform shell formation through solvent vapor exposure

A liquid marble was prepared from bio-based poly(lactic acid) [PLA] microparticles and water droplets. Solvent vapor exposure to the liquid marble changed the morphology of the granular PLA microparticle shell layer to a film-like shell layer even though the spherical shape of the liquid marble is retained. The morphological changes suppressed the evaporation of the water within the liquid marble by a factor of six compared with a liquid marble without the solvent vapor treatment. The compression test revealed that the mechanical stability of the solvent-treated liquid marble was changed due to the increased rigidity of the shell structure. Solvent vapor exposure is a simple but effective way to fabricate a robust liquid marble with long-term stability.