Grafting rates of amine-functionalized polystyrenes onto epoxidized silica surfaces

A comparative study of the grafting of two well-defined, end-functionalized polystyrene samples to the epoxidized surface of a silica substrate was conducted. The two samples were identical except for the steric environment of their functional amine end groups. It was found that the kinetics of layer formation changes throughout the process as the grafted layer becomes more densely packed. A surprising acceleration was observed after the surface attachment density reached a value associated with chain overlap and stretching.