Symmetry-guided, divergent assembly of regio-isomeric molecular Janus particles

Abstract

Varying a single regio-configuration diverges the assembly outcome into distinct morphologies as mandated by their molecular symmetries.

Facile Construction of Porous Magnetic Nanoparticles from Ferrocene-Functionalized Polyhedral Oligomeric Silsesquioxane-Containing Microparticles for Dye Adsorption

“…As perhaps the smallest silica nanoparticle, polyhedral oligomeric silsesquioxanes (POSS) are nanosized, cagelike organic–inorganic hybrid molecules. A typical chemical formula of POSS is (SiO 1.5 R) n ( n = 8, 10, 12), which comprises a rigid inorganic siloxane cage (Si 8 O 12 ) and multiple designable organic substituents (R 8 ). , The inorganic siloxane cage can afford thermal stability and mechanical strength, while the organic substituents provide compatibility and reactivity with polymers. − In the past two decades, POSS have been widely used as nanofillers for enhancing the thermal and mechanical properties of polymers. − As a nanosized cagelike structure, very recently, POSS have also been regarded as a nanobuilding block for the construction of hybrid porous materials. − The resultant hybrid materials inherit the inherent chemical and physical properties of POSS, and they exhibit large surface area, narrow pore-size distribution, good chemical resistance, and high thermal stability, showing attractive application prospects in adsorption, catalysis, energy storage, etc. Notably, such porous materials mainly contain inorganic silica cages and organic linkers, and they are good precursors for the fabrication of carbon and silica materials with a porous nanostructure through selectively removing the silica phase via chemical etching and the organic phase via thermal pyrolysis. ,, …”

Macromolecular Isomerism in Giant Molecules

“…Further increasing the rigidity of the giant molecules by replacing the random‐coil‐like tails with molecular nanoparticles leads to a more profound influence on the self‐assembly behavior. When the crystalline BPOSS motif was employed, the three regio‐isomers of DPOSS‐2BPOSS exhibit similar lamellar crystal structures at a lower temperature, in which crystallization dominates the structure formation . Above the melting point of BPOSS, self‐assembly resembles DPOSS‐2PS n to form phase‐separated nanostructures.…”

Self-Assembly of Poly(Janus particle)s into Unimolecular and Oligomeric Spherical Micelles

“…Despite these successes, the current studies of MNP-based JPs are mainly limited to the AB n topology as well as regulating the number and chemical composition of MNPs, 26,29,30 for generating Janus-like molecules mainly relied on dendrimers 31−33 or polymers 34 with flexible conformations. Herein, we first reported the effort to synthesize a new type of amphiphiles, called poly(Janus particle)s, using molecular Janus particles as repeating units and understand their selfassembly behaviors in solution.…”

“…The synthesis of well-defined nanoscale JPs with molecular precision, high uniformity, and shape and volume persistence is usually challenging. Traditionally, JPs can be constructed by inorganic nanoparticles, colloidal particles, or an amphiphilic flexible polymer chain with special topological structures; however, their large variations in sizes, shapes, or flexible conformation result in limited controllability of their self-assembly to three-dimensional long-range ordered structures. − In this respect, researchers have recently designed and synthesized a set of molecular JPs based on volume and shape-persistent molecular nanoparticles (MNPs), such as fullerene (C60), polyoxometalate (POM), and polyhedral oligomeric silsesquioxanes (POSS) , through efficient chemical transformations like “click” reactions. − The resulting molecular JPs can self-assemble into several unconventional structures in solution and bulk, − attributing to the symmetry breaking in both molecular geometries and chemical interactions. − Besides that, diverse functional groups are able to be efficiently incorporated into MNPs, affording these MNP-based molecular JPs with specific functions. In this regard, constructing molecular JPs using MNPs is not only of scientific importance, but also provides a versatile platform to generate functional materials with nanosized features.…”

“…Despite these successes, the current studies of MNP-based JPs are mainly limited to the AB n topology as well as regulating the number and chemical composition of MNPs, ,, while poly­(Janus particle)­s constructed by volume and shape-persistent MNPs remain largely unexplored. Previous reports for generating Janus-like molecules mainly relied on dendrimers − or polymers with flexible conformations.…”