Predicting the Nucleation Induction Time Based on Preferred Intermolecular Interactions

A key challenge in rationally designing heterogeneous surfaces for controlling crystallization is overcoming the lack of understanding the influence of surface properties has on nucleation. Previous studies hay shown how surface chemistry, can be used to control both nucleation rate and polymorphism. However, these approaches are often empirical and lack any predictive capability. Herein, a novel method, PETI (Predicting Efficacy Through Intermolecular Interactions), for predicting the effectiveness of different polymer surfaces in promoting heterogeneous nucleation is described. PETI utilizes the Cambridge Structural Database to determine the likelihood of forming an intermolecular interaction between solute chemical moieties and polymer surfaces. The concept for PETI is the more likely a solute/polymer interaction, the faster the rate of heterogeneous nucleation. PETI was tested by studying the nucleation of model compounds, benzocaine and 1,1'-bi-2-naphthol, on different polymer surfaces. Results showed that PETIs predictions for the effectiveness of the different polymers at promoting nucleation were in good agreement with experimental observations. This study represents a highly novel approach to predicting the effectiveness of surfaces in promoting crystal nucleation and shows the potential utility of using knowledge of solid-state intermolecular interactions as a tool for the rational design of polymer surfaces for controlling heterogeneous nucleation.