Model Growth: Simulations expose branching nature of polymer crystals

The intricate shapes of snowflakes have long fascinated scientists, but water isn’t the only fluid that freezes into elaborate crystal structures. Polymers and metal alloys do the same. Now, scientists in the United States and Hungary have uncovered previously unknown facets of the physics underlying such crystal growth.

SHAPE SHIFTER. Computer simulations show that adding increasing amounts of impurities to a solidifying polymer (two left-hand columns, top to bottom) produces a more complex structure.