The selectivity of nanoparticles for polydispersed ligand chains during the grafting-to process: a computer simulation study

Abstract

By constructing a grafting-to reaction model of polydispersed polymer chains to bind onto nanoparticles (NPs), we elucidate the changes of grafting density, polydispersity index and chain length distribution of grafted ligand chains as a dependent of the feeding polymer chains. Our study shows a linear dependence of the grafting density on the average chain length of the feeding polymers. We also clearly demonstrate the NP's selectivity of short chains in the later stage of the reaction. Our results also show that the polydispersity of the ligand chains on each individual NP is commonly higher than that of the feeding polymer chains. Furthermore, the simulations imply that polydispersed polymer chains are more easily bound during the grafting-to process compared to monodispersed chains. Thus, relatively higher polydispersity of feeding polymer chains are beneficial to promoting the grafting density of NPs. Our study helps to elucidate the cause of chain polydispersity and could act as a guide to finely regulate the polydispersity of ligand chains on nanoparticles.