Emergence of long-range attractive interactions between colloidal particles during curing of dispersion media

Compared to traditional drying methods, curing processes result in lower emissions of volatile organic compounds and reduced energy consumption. Consequently, curing processes are widely used in the manufacturing of various polymer products, including inks, coatings, composites, and adhesives. In recent years, the functionality of these polymer products has been enhanced by incorporating colloids with antiviral and conductive properties. Despite the significant influence of colloidal arrangement on physical properties, the kinetics of colloidal particles during curing remains poorly understood. To explore the effective interactions between colloidal particles during curing, we investigated the dynamics of soft particles within dispersing media using molecular dynamics simulations. The likelihood of particle aggregation during curing significantly surpasses that of random contact. Our calculations reveal an effective potential, indicating a long-range attractive interaction between the large particles. This attraction results from the heterogeneity in the crosslink network of the dispersing media, distinguishing it from the classical depletion force. Since the structure of particle aggregation could be controlled by the interplay between curing rate and particle diffusion, our findings offer promising prospects for advancing the manufacturing processes of increasingly functional polymeric products.