(220g) “Grafting through” Polymerization

We use a combination of computer simulation and experiments to comprehend â??grafting throughâ? polymerization, i.e., copolymerization of free monomers in solution and polymerizable units bound chemically to a substrate. Free polymer chains are formed initially in bulk solution and if they incorporate at least one surface-bound monomer, the macromolecules get covalently bonded to the surface during the polymerization process. We concentrate specifically on addressing the effect of spatial density of the surface-bound monomers on the formation of the surface-attached polymers. We employ a lattice-based Monte Carlo model based on the bond fluctuation model scheme to provide molecular-level insight into the grafting process. For experimental validation, we create gradients of density of bound methacrylate units on flat silicon wafers using organosilane chemistry and carry out â??grafting throughâ? free radical polymerization initiated in bulk. The proximity of the surface-bound polymerizable units promotes the â??grafting throughâ? process but prevents more free growing chains to â??graft through'' the polymerizable units.