Synthesis of waterborne acrylic/clay nanocomposites by controlled surface initiation from macroinitiator modified montmorillonite

Abstract: The nitroxide mediated controlled surface initiated polymerization of methyl methacrylate (MMA)/butyl acrylate (n-BA) was carried out with a macroinitiator modified montmorillonite. The macroinitiator was synthesized by the nitroxide mediated polymerization of vinylbenzyl trimethylammonium chloride (VBTMACl), methylmethacrylate (MMA) and styrene (S) at 90°C using BlocBuilder®. The macroinitiator was exchanged with the sodium cations of the montmorillonite, to yield surface modified reactive montmorillonite. The bulk polymerizations of BA/MMA from the clay surface produced controlled molecular weight polymers that were able to exfoliate the clay. This controlled polymer/clay nanocomposite was used as masterbatch and further dispersed in monomers and miniemulsified to perform miniemulsion polymerization of BA/MMA (90/10wt.%) at 30wt.% solids content at low emulsifier concentration. The adhesive properties of the nanocomposites prepared with the masterbatch were proved to be better than those prepared with an organically modified clay. [Copyright &y& Elsevier]