(a) Morphological phase diagram of PS144-b-PAA22 in toluene–methanol mixtures as a function of copolymer concentration and solvent composition. Five regions of interest were observed—spheres, vesicles, lamellae, tubes and nanoporous particles—as shown in the inset images. Scale bars represent 200 nm. (b) Formation of the nanoporous particles and the changes of hydrodynamic diameter measured by DLS. (c–g), SEM images showing the morphology evolution with time. The scale bars correspond to 1 μm.