Networks with controlled chirality via self-assembly of chiral triblock terpolymers

Abstract

Nanonetwork-structured materials can be found in nature and synthetic materials. A double gyroid (DG) with a pair of chiral networks but opposite chirality can be formed from the self-assembly of diblock copolymers. For triblock terpolymers, an alternating gyroid (GA) with two chiral networks from distinct end blocks can be formed; however, the network chirality could be positive or negative arbitrarily, giving an achiral phase. Here, by taking advantage of chirality transfer at different length scales, GA with controlled chirality can be achieved through the self-assembly of a chiral triblock terpolymer. With the homochiral evolution from monomer to multichain domain morphology through self-assembly, the triblock terpolymer composed of a chiral end block with a single-handed helical polymer chain gives the chiral network from the chiral end block having a particular handed network. Our real-space analyses reveal the preferred chiral sense of the network in the GA, leading to a chiral phase.

Mesoscale networks and corresponding transitions from self-assembly of block copolymers

“…With the desire to acquire network textures for biomimicking nanomaterials, BCPs with immiscible constituted segments covalently joined together give the accessibility to the formation of nanonetwork morphologies via balancing enthalpic penalty from the repulsive interaction of constituted blocks and entropic penalty from the stretching of polymer chains (17)(18)(19)(20)(21). By taking advantage of precise synthesis procedures, it is feasible to obtain the aimed network phases from the self-assembly of BCPs such as Fddd (O 70 ) (22)(23)(24), gyroid (Q 214 , Q 230 ) (20,21,(25)(26)(27), and diamond (Q 224 , Q 227 ) (28-31) experimentally and theoretically. On the basis of theoretical prediction, the junction points (nodes) in the network phases could be coordinated with three, four, or six neighbors in three-dimensional space, resulting in the enhancement of packing frustration (31).…”

Advanced Electron Microscopy of Nanophased Synthetic Polymers and Soft Complexes for Energy and Medicine Applications

“…Figure 12 is an example of using electron tomography to study the 3D porous structure of polystryrene-block-polyacrylic acid (PS-b-PAA) particles [113]. More examples of using tomography and modeling to resolve polymer nanostructures are provided in Figure 13 [114]. Organic small molecules and polymers form intriguing assemblies and complexes [1][2][3][4][5].…”

Hierarchical self-assembly into chiral nanostructures

“…9b ). 132 Combined with small-angle X-ray scattering (SAXS) profiles, the 2D projections of TEM analysis suggested the formation of an alternating gyroid composed of a pair of gyroid networks. Due to the complicated morphology of the network phase, electron tomography and 3D reconstruction were used to visualize and characterize the chirality.…”

“…9b ). 132 Therefore, such chiral networks are promising candidates for template synthesis to prepare various chiroptical materials with well-defined nanoporosity.…”