MICROFLUIDIC SYNTHESIS OF POLYHEDRAL OLIGOMERIC SILSESQUIOXANE (POSS) BASED ORGANIC-INORGANIC HYBRID MICROPARTICLES
(Supervisor: Assoc.Prof.Dr.Barbaros Çetin )
Mechanical Engineering Department
Utilizing microfluidic systems inevitably changes tools used in chemistry, due to advantages such as handling differential volume, controlled reaction environment, enhanced mixing performance, lesser time required to complete reaction. Hence, microfluidic reactors get more popular among microparticle synthesis tools. This research work presents synthesis of organosilica nano-cage structures, namely Polyhedral oligomeric silsesquioxane (POSS) particles, based on organic-inorganic hybrid microparticles by utilizing dispersion and emulsion polymerization methods. Firstly, POSS microparticles are synthesized via dispersion polymerization method by using continuous flow microreactor on heater and double zone temperature controlled continuous flow microreactor with embedded electrode. Contrary, in conventional batch system, instead of formation of microparticles, nanoclusters are obtained. Synthesized microparticles in microreactors are characterized in terms of morphology, thermal behavior and surface chemical structure. Effects of different parameters such as flow rate, initiator amount and stabilizer amount are presented in embedded electrode microfluidic reactor.
Secondly, in temperature controlled continuous flow microfluidic reactor with embedded thin film electrode, epoxy functional-POSS microparticles have been synthesized via emulsion polymerization method. Heater in microfluidic reactor is designed in Comsol Multiphysics and manufactured in cleanroom to achieve homogenous temperature distribution. Effects of flow rate, temperature and concentration of monomers are presented. Also, same microfluidic reactor without electrodes immersed in oil bath and polymerization is observed and results are compared with the electrode integrated reactor.
DATE: 11 September 2019, Wednesday @ 11:00