A Two‐Stage Kinetics Model for Polydopamine Layer Growth

Abstract Since its introduction, polydopamine coating has played a significant role in the surface modification of various materials, yet a persistent gap exists in understanding its polymerization process. Applying Gompertz' equation, this paper proposes a kinetics model based on the data reported in the literature and obtained at different temperatures and on various substrates. Along with a statistically good regression, the selection of Gompertz' equation is supported by the observed trend in the reported data: regardless of the substrate and the system temperature, the point where 37–40% of the final film thickness is reached precisely coincides with the inflection point of the Gompertz' curve. The proposed kinetics model suggests a two‐stage polymerization process, with the maximum growth rate occurring at 37–40% of the final film thickness. The maximum growth rate increases with temperature. However, at higher temperatures, the system needs more time to reach the maximum growth rate.