Brownian molecular dynamics simulations are carried out on the self-assembly behavior of rod−coil diblock copolymers. The copolymer molecule is represented by a linear chain consisting of definite beads connecting by harmonic bond stretching potential. The rigidity of the rod block is introduced by harmonic potential for bend at a substantially zero bond angle. The micelle structures formed by such copolymers and molecular packing of rod blocks are investigated. Transitions of aggregate structure are found with changing Lennard-Jones (LJ) interaction εRR of rod pairs. The rod blocks tend to align orientationally and pack hexagonally in the core to form a smectic-like disk structure at the higher εRR. With decreasing εRR, a disk micelle is gradually changed to a new string structure, where the twisting of rod blocks packing in the core has been discovered and further breaks into some small aggregates until unimers. The radius of gyration and order parameter of rod blocks are calculated to confirm such a transition from disk to string structure. The regions of thermodynamic stability of disk, string, and small aggregates are constructed in the diagrams of block chain length against εRR and temperature vs εRR. Increase of the rod block length leads to a more dramatic decrease of the critical micelle interaction (CMI) than decrease of the coil block length does. The onsets of string and disk formation move to higher εRR with decreasing rod block length and/or increasing coil length. Meanwhile, the regions of string micelle and small aggregates become wider. Some simulation results are in agreement with existing experimental observations and theoretical predictions.

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Inorganic nanoparticles have become a research focus in numerous fields because of their unique properties that distinguish them from their bulk counterparts. Controlling the size and shape of nanoparticles is an essential aspect of nanoparticle synthesis. Preparing inorganic nanoparticles by using block copolymer templates is one of the most reliable routes for tuning the size and shape of nanoparticles with a high degree of precision. In this Review, we discuss recent progress in the design of block copolymer templates for crafting spherical inorganic nanoparticles including compact, hollow, and core-shell varieties. The templates are divided into two categories: micelles self-assembled from linear block copolymers and unimolecular star-shaped block copolymers. The precise control over the size and morphology of nanoparticles is highlighted as well as the useful properties and applications of such inorganic nanoparticles.

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As you like it: The synthesis of supramolecular hierarchical nanostructures with designed morphologies has been realized through computer-simulation-guided multicomponent assembly of polypeptide-based block copolymers and homopolymers. By adjusting the attraction between hydrophobic polypeptide rods, as well as other parameters such as the molar ratio of copolymers and the rigidity of polymers, a variety of morphologies were obtained.

We report here a discovery that amphiphilic polypeptide block copolymers and polypeptide homopolymers are able to aggregate together into super-helical structures of rods and rings, in which polypeptide chains form the core and PEG chains form the shell.

Ordered mesoporous metal–organic frameworks (mesoMOFs) were constructed with a uniform pore size up to about 10 nm and thick microporous walls, opening up the possibility for the mass diffusion of large‐size molecules through crystalline MOFs. The synergistic effects based on triblock copolymer templates and the Hofmeister salting‐in anions promote the nucleation of stable MOFs in aqueous phase and the in situ crystallization of MOFs around templates, rendering the generation of a microcrystal with periodically arranged large mesopores. The improved mass transfer benefiting from large‐pore channels, together with robust microporous crystalline structure, endows them as an ideal nanoreactor for the highly efficient digestion of various biogenic proteins. This strategy could set a guideline for the rational design of new ordered large‐pore mesoMOFs with a variety of compositions and functionalities and pave a way for their potential applications with biomacromolecules.

A theoretical approach combining self-consistent-field theory (SCFT) for fluids and density functional theory (DFT) for particles was applied to investigate the self-assembly behavior of amphiphilic diblock copolymer/nanoparticle mixture in dilute solution. Two kinds of hydrophobic nanoparticles are studied:  one is that the particles are selective to hydrophobic blocks but are incompatible with hydrophilic blocks, and the other is that the particles are nonselective to hydrophobic and hydrophilic blocks. For both cases, the self-association of amphiphilic block copolymer/nanoparticle mixture is observed, and the nanoparticles are spatially organized in the clusters. The aggregate morphologies can be tuned by the particle radius and particle volume fraction. For the selective particles, the aggregate morphologies of amphiphilic block copolymer/nanoparticle mixture can experience a transition from vesicles to mixture of circlelike and rod micelles as the particle radius and/or particle volume fraction increase. For the nonselective nanoparticles, the large compound micelles are produced instead of the vesicles. The large compound micelles transform to the mixture of large compound micelles and circlelike micelles with an increase in particle volume fraction and/or radius. The distribution of nanoparticles in the clusters is also affected by the particle radius and volume fraction. For both cases, when the values of nanoparticle radius and/or volume fraction are small, the nanoparticles are almost uniformly distributed in the cores of micelles. However, the particles tend to localize near the interfaces between the core and shell with increasing particle volume fraction and/or radius.