Crystal nucleation of polymers confined to droplets: Memory effects

We study crystal nucleation within an ensemble of polyethylene droplets created through the dewetting of a thin film on an unfavorable substrate. In particular, we employ standard thermal treatment procedures to induce self‐nucleation in samples to gain some insight into the nature of this enhanced crystallization. The novel sample‐geometry enables the monitoring of each droplet throughout successive experiments, and hence the changes in their nucleation mechanism for various thermal treatments. We find a consistent self‐nucleated crystallization temperature of ∼101 °C under all conditions, suggesting uniformity in the centers which facilitate nucleation. Using correlation plots, we demonstrate that the observed melt‐memory effects have a stochastic rather than deterministic nature; self‐nucleation is a random process.