Making ordered nanostructures in polymers and their thin films is an important technique to produce functional materials. Herein, we report instant yet precise self-assembly systems of amphiphilic random copolymers to build multilayered lamellar structures in bulk materials and thin films. Random copolymers bearing octadecyl groups and hydroxyethyl groups induced crystallization-driven microphase separation via simple evaporation from the solutions to form lamellar structures in the solid state. The domain spacing was controlled in the range between 3.1 and 4.2 nm at the 0.1 nm level by tuning copolymer composition. Interestingly, just by spin-coating the polymer solutions onto silicon substrates, the copolymers autonomously formed thin films consisting of multilayered lamellar structures, where amorphous/hydrophilic parts and crystalline octadecyl domains are alternatingly layered from a silicon substrate to the air/polymer interface at regular intervals. The lamellar domain spacing was tunable by selecting hydrophilic pendants.

Sub-10 nm lamellar structures are efficiently constructed by the pendant microphase separation of amphiphilic crystalline random copolymers with broad molecular weight distribution that are obtained from free radical copolymerization.

Reversible self-sorting and co-self-assembly systems of amphiphilic synthetic molecules in water would bring innovative methodologies in creating repeatedly transformable multicomponent self-assemblies that are responsive to the outer environment and stimuli. Herein, we report reversible co-self-assembly and self-sorting systems of the binary blends of amphiphilic random copolymers bearing quaternary ammonium cation and dodecyl groups and those carrying poly(ethylene glycol) (PEG) chains and dodecyl groups in water. The cation copolymers co-self-assembled with the PEG copolymers to form cation/PEG-fused micelles in pure water, while the fused micelles self-sorted into discrete cation or PEG micelles in the presence of salts. Importantly, those random copolymers reversibly switch association partners in response to the presence or absence of salts in water. The size of the fused micelles was dependent on their copolymer composition but independent of the mixing ratio of cation and PEG copolymers. The fused micelles thus coexisted with the extra amount of cation or PEG micelles. We further revealed that the co-selfassembly and self-sorting of their copolymers are driven by the exchange of polymer chains between micelles like the exchange of subdomains in protein self-assemblies.