Synthesis of microcapsules via reactive surfactants

A statistical library of well-defined ionic and non-ionic amphiphilic block copolymers of P(MMA/HEMA)-b-PDMAEMA and PEG-b-P(MMA/HEMA) were synthesised via living radical polymerisation employing the macroinitiator technique. All the block copolymers show monomodal peaks and narrow weight distributions, indicating they were obtained in controlled manner. Those copolymers were further modified in order to prepare inisurfs and surfmers. This yielded a selection of active surfactants of desired molecular weight and low polydispersity. Soap-free miniemulsion polymerisations of butyl methacrylate were carried out using the obtained active surfactants to prepare core-shell microcapsules in which various concentrations of inert oil, hexadecane, as a model system were encapsulated. The influence of the block copolymer structure on the particle formation was studied. The core-shell nature of the particles could be confirmed using scanning electron microscopy. Up to 66% of hexadecane could be incorporated in PBMA microcapsules.