Solvent quality shape control in continuous flow block copolymer self-assembly†

Effects of solvent quality on block copolymer (BCP) self-assembly in flow are investigated. Stable kinetically trapped nanoaggregates are created using a continuous flow technique with turbulent mixing under systematically changing THF/water ratios. To elucidate particles morphologies, small angle neutron scattering (SANS) is used as an online analytical method. At high organic solvent contents, elongated particles are observed while at low contents shorter particles are formed. The method can hence be used in a versatile way to control particle morphologies without changing the BCP block lengths used for self-assembly. This offers a more efficient and flexible approach in drug delivery and biomedical applications where particle morphologies directly influence the cell uptake capabilities and reduces the need to resynthesize BCPs with varying block lengths to control size and morphology.