When phase separation freezes mid-way: Cahn-Hilliard with gelation
Colloidal particles with short-range attraction undergo spinodal decomposition: phase-separated into dense (gel) and dilute regions via Cahn-Hilliard:
∂φ/∂t = ∇²(−∇²φ + f'(φ))
When local density exceeds φ_gel, gelation arrests the coarsening — the network freezes into a disordered, stress-bearing solid (colloidal gel).
This creates bicontinuous networks with fractal dimension ~2.4, unlike macro-phase-separated fluids. Applications: food gels (yogurt), aerogels, tissue scaffolds, battery electrodes.
Color: bright = dense/gelled phase, dark = dilute phase. Gelled regions (white outline) are frozen.