Defects and defect engineering in Soft Matter

Abstract

Defect engineering is a success story in crystalline hard matter; this review summarizes its parallels in amorphous soft matter.

Defect-controlled softness, diffusive permeability, and mesh-topology of metallo-supramolecular hydrogels

“…Defect engineering in soft matter is a wide field of research that allows for tuning material properties on multiple levels. 1 In one branch of that discipline, structural inhomogeneities affect the properties of polymer-network gels, specifically the local and global elasticity, 2 fracture mechanism, 3 and the diffusive permeability of guest substances, 4 and since these properties lay the ground for the main applications of gels, the impact and ability of controlling such inhomogeneities is crucial. Prominent examples for inhomogeneities are found in hydrogels, which are three-dimensional polymer networks swollen in water.…”

“…A recent review on defect engineering in soft matter highlights the utmost importance of structure control to implement a novel type of rational material design based on these aforementioned minor structural deviations. 1…”

Control of extrinsic porosities in linked metal-organic polyhedra gels by imparting coordination-driven self-assembly with electrostatic repulsion

“…This method is more characteristic of amorphous networks that offer structural freedom within the material. 30 Although the similar method can be applied to crystalline MOFs, the changing of connectivity on the metal nodes requires the introduction of defects and at the extreme case leads to the collapse of crystalline networks. [31][32] One of the drawbacks to investigate the amorphous network is to determine the exact network structures and to give feedback to the synthetic conditions.…”

Screw dislocation-induced pyramidal crystallization of dendron-like macromolecules featuring asymmetric geometry

“…[1][2][3] In order to control the crystal phase and material properties, various crystal engineering strategies are applied such as structure modification and regulation of molecular concentration, orientation, and nucleation rate through solution and vapor processing methodologies. [4][5][6][7][8] Under the influence of stress or impurity, real crystals always have structural disorders which introduce heterogeneity without losing long-range order. Due to the atom(s) locating at irregular positions, many interesting and unexpected supramolecular architectures were observed.…”