Sugar-based block copolymers (BCPs) have emerged as a class of green material capable of self-assembling into ordered structures with sub-10 nm feature size in the oligomeric regime. Here, we reveal the strong effects of molecular architecture and configuration on the self-assembly behavior of the monodisperse maltose (Glc 2 )solanesol (Sol) BCPs bearing linear and A 2 B 2 miktoarm star architectures in the complex phase window. Double gyroid (DG) and hexagonal perforated layer (HPL) with ABC stacking of the perforation were observed with strong architectural effects on their order−order transition (OOT) behavior. The oligomeric nature of the miktoarm star BCP amplified the role of the configuration prescribed by the substituted positions of the block chains at the benzene core. The trans configuration set by the 1,4-substitution of the two Glc 2 blocks at the core exerted a stronger steric hindrance to the formation of hydrogen bonding of Glc moiety than the cis configuration prescribed by the 1,3-substitution. The more effective formation of hydrogen bonding in the cis-star BCP led to a stronger resistance against the bending of the sugar domain interface and hence narrowed down the window of the higher-curvature morphology. The HPL-to-DG transition was intervened by the Fddd phase in the trans-star copolymer, which was attributed to the larger asymmetry in the unit cell dimensions of the hexagonal unit cell of HPL phase.

Carbohydrates are key building blocks for advanced functional materials owing to their biological functions and unique material properties. Here, we propose a star-shaped discrete block co-oligomer (BCO) platform to access carbohydrate nanostructures in bulk and thin-film states via the microphase separation of immiscible carbohydrate and hydrophobic blocks (maltooligosaccharides with 1–4 glucose units and solanesol, respectively). BCOs with various star-shaped architectures and saccharide volume fractions were synthesized using a modular approach. In the bulk, the BCOs self-assembled into common lamellar, cylindrical, and spherical carbohydrate microdomains as well as double gyroid, hexagonally perforated lamellar, and Fddd network morphologies with domain spacings of ∼7 nm. In thin films, long-range-ordered periodic carbohydrate microdomains were fabricated via spin coating. Such controlled spatial arrangements of functional carbohydrate moieties on the nanoscale have great application potential in biomedical and nanofabrication fields.

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