Microfluidic synthesis of polyhedral oligomeric silsesquioxane (POSS) based organic-inorganic hybrid microparticles

Abstract

Utilizing micro uidic systems inevitably changes tools used in chemistry due to advantages such as handling differential volume, controlled reaction environment, enhanced mixing performance, less time required to complete reaction. Hence micro uidic reactors become more popular among microparticle synthesis tools. This research work presents synthesis of organosilica nano-cage structures, namely Polyhedral oligomeric silsesquioxane (POSS) particles, based on organicinorganic hybrid microparticles by utilizing dispersion and emulsion polymerization methods. Firstly, poly(M-POSS) microparticles are synthesized via dispersion polymerization method by using continuous ow microreactors, one of which is operated on a hot plate and the other one has temperature controlled dual zone with embedded electrodes. Synthesized microparticles in microreactors are characterized in terms of morphology, thermal behavior and surface chemical structure. Effects of different parameters such as monomer, initiator and stabilizer amount are presented. Secondly, in a temperature controlled continuous ow micro uidic reactor with embedded thin film electrode, epoxy functional- POSS microparticles have been synthesized via emulsion polymerization method. Heater for the micro uidic reactor is designed by COMSOL Multiphysics and manufactured in cleanroom to achieve homogeneous temperature distribution. Effects of ow rate, temperature and concentration of monomers are presented. In addition, same micro uidic reactor without electrodes immersed in oil bath and polymerization is observed and results are compared with the electrode integrated reactor.