Block copolymers as polymeric stabilizers in non-aqueous emulsion polymerization

This review summarizes the background and recent advances of block copolymer stabilized oil-in-oil emulsions. For non-polymerizable emulsions which have promising application possibilities for biomedical and cosmetic formulations, it is shown that tailor-made block copolymers are by far the most efficient stabilizers with respect to low molecular weight surfactants. The characteristic features of oil-in-oil emulsions comprising one polymerizable phase are described. These types of nonaqueous emulsions are of interest as nanoreactor systems for the polymerization of moisture-sensitive monomers or catalysts. Furthermore they are the starting point of novel heterophase polymerization processes for the preparation of sterically stabilized polymer particles, as well as of 'liquid-filled polymeric materials'. The concept of oil-in-oil emulsions is finally extended to those systems where the two phases are polymerizable by distinct polymerization mechanisms. This approach could offer attractive possibilities for the development of special coatings with neither water nor solvent evaporation in their drying or curing step. (C) 2011 Society of Chemical Industry