Shape formation in interfacial flows

Interfacial fluid dynamics has a rich history of systematically exploring intricate flows studied for their technological and heuristic value. Surface tension typically forms exceptionally smooth shapes, yet the same cohesive forces can precipitate the rearrangement and breakup of liquids through a wealth of hydrodynamic instabilities. This article summarizes, albeit nonexhaustively, recent efforts to tame interfacial flows in solidifying polymer melts. The article tackles both these flows' stable and unstable limits and focuses on the fundamental challenges and opportunities of harnessing interfacial effects to shape soft materials.