Hierarchical Self-Assembly and Digital Memory Characteristics of Crystalline–Amorphous Brush Diblock Copolymers Bearing Electroactive Moieties

Abstract

Two series of crystalline−amorphous brush diblock copolymers bearing electroactive moieties were newly synthesized by sequential anionic ring-opening copolymerizations of glycidyl derivatives and subsequent selective postfunctionalizations; their homopolymers and analogues were additionally synthesized. Self-assembly structural details and electrical memory behaviors of these polymers in nanoscale thin films were investigated. The diblock copolymers revealed complex hierarchical self-assembly structures depending on the compositions. The self-assembly structure and orientation of the crystalline block chains were severely affected by the geometrical confinement (i.e., size and shape) stemming from microphase separation. Such film morphologies were found to significantly influence the electrical properties; they exhibited electrical properties from p-type permanent memory behavior to dielectric-like behavior. The memory behaviors were governed by the trap-limited space charge limited conduction mechanism combined with ohmic conduction and the hopping paths composed of the electroactive moieties distributed locally.

Precise Synthesis of Functional Block Copolymers by Living Anionic Polymerization of Vinyl Monomers Bearing Nitrogen Atoms in the Side Chain

“…Synthetic routes of PGROH m ‐PGBPRK n and PGROH m ‐PGRBPK n . Reproduced with permission . Copyright 2016, American Chemical Society.…”

“…Schematic representations of the hierarchical self‐assembly structures formed in the solvent‐annealed PGROH m −PGBPRK n and PGROH m −PGRBPK n films: (A) PGROH 52 −PGBPRK 68 (23/77, v/v) and PGROH 40 −PGRBPK 65 (21/79, v/v), (B) PGROH 84 −PGBPRK 37 (47/53, v/v) and PGROH 84 −PGRBPK 37 (47/53, v/v), and (C) PGROH 102 −PGBPRK 14 (74/26, v/v) and PGROH 107 −PGRBPK 13 (78/22, v/v). Reproduced with permission . Copyright 2016, American Chemical Society.…”

Conception of Stretchable Resistive Memory Devices Based on Nanostructure‐Controlled Carbohydrate‐block‐Polyisoprene Block Copolymers

“…In particular, polymer‐based memory devices have shown their advantages for applications because of the low fabrication cost, solution processability, flexibility, high mechanical strength, and good scalability . On the other hand, the versatile memory behaviors, including volatile or nonvolatile digital memories such as dynamic‐random‐access‐memory (DRAM), static‐random‐access‐memory, and write‐once‐read‐many‐times (WORM), of polymer‐based devices could be manipulated through the donor/acceptor characteristics or the nanostructures of the polymer active layer . However, to the best of our knowledge, stretchable electronic polymers using carbohydrate‐based polymers for the resistive memory application have not been reported yet.…”

Polymethylene-b-poly(acrylic acid) diblock copolymers: Morphology and crystallization evolution influenced by polyethyene polyamine with dual confinement effects

“…In recent years, block copolymers (BCPs) have attracted abiding interest, owing to their various morphologies in bulk or solution, [1][2][3][4] which is caused by the thermodynamic incompatibility of the different polymer segments. [5][6][7] The morphologies are mainly including spheres, cylinders, lamellae and vesicles.…”