Dual‐Phase Separation in a Semiconfined System: Monodispersed Heterogeneous Block‐Copolymer Membranes for Cell Encoding and Patterning

Block copolymers (BCPs) have the capacity to self‐assemble into a myriad of well‐defined aggregate structures, offering great promise for the construction of drug delivery, photolithographic templates, and complex nanoscale assemblies. A uniqueness of these materials is their propensity to become kinetically frozen in non‐equilibrium states, implying that the process of self‐assembly can be utilized to remodel the resulting structures. Here, a new semiconfined system for processing the BCP self‐assembly is constructed, in which an unusual dual‐phase separation occurs, including nonsolvent‐induced microphase separation and osmotically driven macrophase separation, ultimately yielding heterogeneous BCP membranes. These membranes with cellular dimensions show unique anisotropy that can be used for cell encoding and patterning, which are highly relevant to biology and medicine. This processing method not only provides new levels of tailorability to the structures and encapsulated contents of BCP assemblies, but can also be generalized to other block polymers, particularly those with attractive electronic and/or optical properties.     

Performance Enhancement of Electronic and Energy Devices via Block Copolymer Self‐Assembly

The use of self‐assembled block copolymers (BCPs) for the fabrication of electronic and energy devices has received a tremendous amount of attention as a non‐traditional approach to patterning integrated circuit elements at nanometer dimensions and densities inaccessible to traditional lithography techniques. The exquisite control over the dimensional features of the self‐assembled nanostructures (i.e., shape, size, and periodicity) is one of the most attractive properties of BCP self‐assembly. Harmonic spatial arrangement of the self‐assembled nanoelements at desired positions on the chip may offer a new strategy for the fabrication of electronic and energy devices. Several recent reports show the great promise in using BCP self‐assembly for practical applications of electronic and energy devices, leading to substantial enhancements of the device performance. Recent progress is summarized here, with regard to the performance enhancements of non‐volatile memory, electrical sensor, and energy devices enabled by directed BCP self‐assembly.