Droplet-like Defect Annihilation Mechanisms in Hexagonal Cylinder-Forming Block Copolymers

The annihilation of typical individual defects in hexagonal cylinder-forming block copolymers is investigated using the self-consistent field theory (SCFT) in conjunction with the string method. Usually, defect removal in two-dimensional hexagonal patterns involves reorganizing the cylindrical domains. Unlike atoms in solid crystals, the self-assembled cylindrical domains of block copolymers are “soft”. Thus, the kinetic motions of the cylindrical domains resemble liquid droplets. Dislocations in hexagonal patterns are eliminated via creating and removing cylindrical domains. Our results show that new cylindrical domains are created via either a nucleation-like process or a fission-like process, whereas excessive domains are eliminated via a fusion-like or evaporation-like process. For weakly segregated block copolymers, the nucleation-like and evaporation-like processes are preferred

Crystal Structure of Novel Polyamides with Long Diacid Segment: Polyamides 2 16, 4 16, 6 16, 8 16, 10 16, and 12 16

The morphologies of a series of novel polyamides with a long diacid segment were carefully studied using transmission electron microscopy (TEM), while their crystal structure was investigated using both TEM and wide-angle X-ray diffraction (WAXD). It was seen that the solution-grown crystals of all polyamides in this work were lath-like and crystallized as chain-folded, hydrogen-bonded sheet lamellae from 1,4-butanediol. The electron diffraction of these samples reveals that two crystalline phases are present including both αp and βp in all polyamides under consideration except for polyamide 2 16, which only consists of one crystal form, αp. In addition, sedimented mats of these polyamide crystals and stretched film samples were examined by WAXD. The unit cell parameters for these crystals were calculated thereinafter

Accelerated Method of Self-Consistent Field Theory for the Study of Gaussian Ring-Type Block Copolymers

Although self-consistent field theory (SCFT) has been become one of the most successful methods for the study of block copolymers, its application to ring copolymers has been hindered for years, especially for three-dimensional structures. Here, we have developed an accelerated pseudospectral algorithm to solve SCFT equations of ring copolymers by taking advantage of the symmetry of ordered structures. By combining various advanced techniques, speed-up of orders of magnitude has been achieved, making the construction of a complete phase diagram affordable. This accelerated algorithm has been applied to constructing the phase diagrams of AB ring and AB tadpole copolymers, consisting of the double gyroids, O70, and even Frank–Kasper spherical phases. This algorithm is applicable for the studies of other ring copolymers that will add a piece of puzzle to the understanding of architectures on the self-assembly behavior of block copolymers

Droplet-like Defect Annihilation Mechanisms in Hexagonal Cylinder-Forming Block Copolymers

The annihilation of typical individual defects in hexagonal cylinder-forming block copolymers is investigated using the self-consistent field theory (SCFT) in conjunction with the string method. Usually, defect removal in two-dimensional hexagonal patterns involves reorganizing the cylindrical domains. Unlike atoms in solid crystals, the self-assembled cylindrical domains of block copolymers are “soft”. Thus, the kinetic motions of the cylindrical domains resemble liquid droplets. Dislocations in hexagonal patterns are eliminated via creating and removing cylindrical domains. Our results show that new cylindrical domains are created via either a nucleation-like process or a fission-like process, whereas excessive domains are eliminated via a fusion-like or evaporation-like process. For weakly segregated block copolymers, the nucleation-like and evaporation-like processes are preferred

Droplet-like Defect Annihilation Mechanisms in Hexagonal Cylinder-Forming Block Copolymers

The annihilation of typical individual defects in hexagonal cylinder-forming block copolymers is investigated using the self-consistent field theory (SCFT) in conjunction with the string method. Usually, defect removal in two-dimensional hexagonal patterns involves reorganizing the cylindrical domains. Unlike atoms in solid crystals, the self-assembled cylindrical domains of block copolymers are “soft”. Thus, the kinetic motions of the cylindrical domains resemble liquid droplets. Dislocations in hexagonal patterns are eliminated via creating and removing cylindrical domains. Our results show that new cylindrical domains are created via either a nucleation-like process or a fission-like process, whereas excessive domains are eliminated via a fusion-like or evaporation-like process. For weakly segregated block copolymers, the nucleation-like and evaporation-like processes are preferred

Droplet-like Defect Annihilation Mechanisms in Hexagonal Cylinder-Forming Block Copolymers

The annihilation of typical individual defects in hexagonal cylinder-forming block copolymers is investigated using the self-consistent field theory (SCFT) in conjunction with the string method. Usually, defect removal in two-dimensional hexagonal patterns involves reorganizing the cylindrical domains. Unlike atoms in solid crystals, the self-assembled cylindrical domains of block copolymers are “soft”. Thus, the kinetic motions of the cylindrical domains resemble liquid droplets. Dislocations in hexagonal patterns are eliminated via creating and removing cylindrical domains. Our results show that new cylindrical domains are created via either a nucleation-like process or a fission-like process, whereas excessive domains are eliminated via a fusion-like or evaporation-like process. For weakly segregated block copolymers, the nucleation-like and evaporation-like processes are preferred

Droplet-like Defect Annihilation Mechanisms in Hexagonal Cylinder-Forming Block Copolymers

The annihilation of typical individual defects in hexagonal cylinder-forming block copolymers is investigated using the self-consistent field theory (SCFT) in conjunction with the string method. Usually, defect removal in two-dimensional hexagonal patterns involves reorganizing the cylindrical domains. Unlike atoms in solid crystals, the self-assembled cylindrical domains of block copolymers are “soft”. Thus, the kinetic motions of the cylindrical domains resemble liquid droplets. Dislocations in hexagonal patterns are eliminated via creating and removing cylindrical domains. Our results show that new cylindrical domains are created via either a nucleation-like process or a fission-like process, whereas excessive domains are eliminated via a fusion-like or evaporation-like process. For weakly segregated block copolymers, the nucleation-like and evaporation-like processes are preferred

Module genes identified via WGCNA in OB dataset (GSE2508).

(a) β = 6 is selected as the soft threshold with the combined analysis of scale independence and average connectivity. (b) Clustering dendrogram of the OB and normal samples. (c) Gene co-expression modules represented by different colors under the gene tree. (d) Heatmap of the association between modules and OB.</p