Fig. 1.

(A): The first row shows microscopic images of thermally induced phase separation in a gelatin–PEG mixture at 4 ${}^{°}$C with increasing time. Each droplet measures 50 microns in diameter. Experimental details are provided in Appendix A. The second row plots a volume rendering of a three-dimensional simulation of liquid–liquid phase separation using the Cahn–Hilliard–Stokes–Boussinesq model developed in Section 1B (corresponding to model CHSB $x$ in Fig. 8). Simulation parameters are detailed in Tables 1–3. The simulation time $t$ is nondimensional and must be rescaled to correspond to the physical time $T$ of the experimental snapshots, as we use an artificially large interfacial thickness parameter $\epsilon$ (detailed in SI Appendix). The patterns of phase separation evolving over time are in qualitative agreement. (B): Schematic of minimal-energy crescent-shaped particle at equilibrium for given surface tensions (red, green, blue) and contact angles (purple, orange, gray) of gelatin-rich ($c_1$), PEG-rich ($c_2$), and surrounding oil ($c_3$) phases.