  Micro-droplets of soft matter solutions have different morphologies upon
drying, and can finally become wrinkled, buckled or cavitated particles. We
investigate the morphology evolution of a drying soft matter droplet in this
work: at the early stage of drying, wrinkling or cavitation instability can
occur in the droplet, depending on the comparison between the critical
wrinkling and cavitation pressure; at a later stage of drying, no wrinkle will
appear if cavitation happens first, while there can still be cavitation if
wrinkling happens first. A three-dimensional phase diagram in the space of
elastic length, gel layer thickness and weight loss is provided for
illustrating these drying pathways of a soft matter droplet, which can guide
future fabrications of micro-particles with desired morphologies.
