Investigation of off-Chip and on-Chip Self-Assembly of Amphiphilic Diblock Copolymers Based on Poly(dimethylsiloxane) and Poly(oligo(ethylene glycol)methacrylate)

Abstract This study aims to optimize the molecular architecture of poly(dimethylsiloxane)-b-poly(oligo (ethylene glycol) methacrylate) (PDMS-b-POEGMA) amphiphilic copolymers and investigate the phase behavior in solutions via alteration of chemical composition, initial concentrations of copolymers, none-solvent entry rates in the dialysis method, and also alterations in the micelle preparation methodology. To this end, PDMS-b-POEGMA copolymers are synthesized with different compositions and sequence lengths. Careful monitoring of the morphological permutations of polymeric nanoparticles in aqueous solution is performed through the dialysis method as an off-chip approach. Spherical and rod morphologies with different sizes are acquired due to variations in the properties of copolymer solutions such as chemical composition, concentration and the rate of water as non-solvent. For the on-chip process, a suitable microfluidic reactor is designed via a Shrinky-Dink method to produce micelles and compare them with micelles prepared by the dialysis method. Applying the on-chip method decreases the particle size from 500 to 50 nm, and reduces the particle size distribution from about 0.8 to 0.4. Hence, the particles reached from the microfluidic technique are smaller with a narrower particle size distribution, compared to those obtained from the off-chip method.