Self-assembly Promoted Crystallization of Diblock Copolypeptoids in Solution†

Great efforts have been lately devoted to fabricating well-defined nanostructures using crystallization-driven self-assembly (CDSA) strategy. The influence of self-assembly on crystallization is also of great interest. Here, a series of amphiphilic diblock copolypeptoids poly(N-allylglycine)-b-poly(N-octylglycine) modified with cysteamine hydrochloride ((PNAG-g-NH2)-b-PNOG) were synthesized by ring-opening polymerization (ROP) and post-polymerization functionalization. The diblock copolypeptoid is comprised of one hydrophobic crystalline PNOG block and one hydrophilic amorphous block, which can aggregate into nanostructured assemblies with soluble PNAG-g-NH2 as the corona layer and PNOG as the inner core in aqueous solution. With a systematic study by differential scanning calorimetry (DSC) and wide-angle X-ray scattering (WAXS), we demonstrated that the self-assembly of the block copolymers strengthens the crystallization of the PNOG block.