Nonequilibrium Nature of Flow-Induced Nucleation in Isotactic Polypropylene
Citations Over TimeTop 10% of 2015 papers
Abstract
Based on classical nucleation theory, the current entropic reduction model (ERM) of flow-induced crystallization (FIC) treats external work as perturbation on the framework of equilibrium thermodynamics, which, however, obscures the nonequilibrium nature of FIC. In this work, in situ investigation on FIC under strong flow by combining a unique homemade extensional rheometer and ultrafast X-ray scattering reveals a constant critical strain or time for nucleation in isotactic polypropylene melt in a wide temperature range from 130 to 170 °C. Our discovery contradicts the strain–temperature equivalence predicted by ERM but unveils the nonequilibrium nature of FIC. To account for the temperature independence of flow-induced nucleation, a tentative kinetic pathway of nucleation describing stretch-induced hierarchical structural transitions is proposed through which the capability of flow as driving force is justified.
Related Papers
- → Classical nucleation theory approach to two-step nucleation of crystals(2019)74 cited
- → Kinetic analysis of homogeneous droplet nucleation using large-scale molecular dynamics simulations(2018)39 cited
- → A nanoscale temperature-dependent heterogeneous nucleation theory(2015)4 cited
- Bubble Nucleation During Free Foaming in Polyethylene Based on Classical Nucleation Theory(2013)
- Molecular Dynamic Simulation on Homogeneous Nucleation Rate of Argon Vapor(2009)