Divining the Shape of Nascent Polymer Crystal Nuclei

Abstract

We demonstrate that nascent polymer crystals (i.e., nuclei) are anisotropic entities, with neither spherical nor cylindrical geometry, in contrast to previous assumptions. In fact, cylindrical, spherical, and other high symmetry geometries are thermodynamically unfavorable. Moreover, post-critical transitions are necessary to achieve the lamellae that ultimately arise during the crystallization of semicrystalline polymers. We also highlight how inaccurate treatments of polymer nucleation can lead to substantial errors (e.g., orders of magnitude discrepancies in predicted nucleation rates). These insights are based on quantitative analysis of over four million crystal clusters from the crystallization of prototypical entangled polyethylene melts. New comprehensive bottom-up models are needed to capture polymer nucleation.

arXiv comment19 pages long with 5 figures

References in corpus (6)

• Direct Calculation of Ice Homogeneous Nucleation Rate for a Molecular Model of Water
• Homogeneous and heterogeneous nucleation of Lennard-Jones liquids
• Kinetic Monte Carlo simulations of the growth of polymer crystals
• Crystallization of a polymer on a surface
• Local Structure Order Assisted Two-step Crystal Nucleation in Polyethylene
• Continuum Theory of Polymer Crystallization

Cited by in corpus (1)

• Property Decoupling across the Nucleus-Melt Interface during Polymer Crystal Nucleation