Self-Assembly of a Strong Polyhedral Oligomeric Silsesquioxane Core-Based Aspartate Derivative Dendrimer Supramolecular Gelator in Different Polarity Solvents

Abstract

Aromatic groups are introduced into the end peripherals of polyhedral oligomeric silsesquioxane (POSS) core-based organic/inorganic hybrid supramolecules to get a novel dendrimer gelator POSS-Z-Asp(OBzl) (POSS-ASP), which have eight aspartate derivative arms to make full use of strong π-π stacking forces to get strong supramolecular gels in addition to multiple hydrogen bindings and van der Waals interactions. POSS-ASP can self-assemble into three-dimensional nanoscale gel networks to provide hybrid physical gels especially with strong mechanical properties and fast-recovery behaviors. Two totally different morphologies of the connected spherical particle structures and banded ultralong fibers are observed owing to the polarity of solvents confirmed by the scanning electron microscopy, polarized optical microscopy, and transmission electron microscopy techniques, expecting the existing various self-assembly models and illustrating the peripherals of the dendrimer and the polarity of solvents having huge influences in the supramolecular self-assembly mechanism. What is more, the thermal stability, rheological properties, and network architecture information have also been investigated via tube-inversion, rotational rheometer, and powder X-ray diffraction methods, the results of which confirm the two different gel formation mechanisms that make POSS-ASP to exhibit two totally different thermal and mechanical properties. Such a study reports a new gelation system in organic or organic/aqueous mixed solvents, which can be helpful for investigating the relationship of dendritic supramolecular gelation and different polarity solvents during the supramolecular self-assembly process of gelators.

Computer simulation study on the self-assembly of tethered nanoparticles with tunable shapes

“…When the chain is short (n ¼ 3, 5), the selfassembly structures are greatly affected by the shape of nanocubes: the rigid cubic heads are packing in face-to-face manner and form the framework of columnar structures (as shown the movie in ESI †), while the tethered chains distribute in the channels of the framework, similar to the structure obtained in experiments. 42 Obviously, the diameter of the channel in the case of n ¼ 3 is smaller than that in the case of n ¼ 5, which implies that it is possible to tune the chain length and type to control the channel size and interior property, and the corresponding material may be used as responsive lters. These framework structures are still quite stable in higher concentrations.…”

Metal Oxide-Related Dendritic Structures: Self-Assembly and Applications for Sensor, Catalysis, Energy Conversion and Beyond

“…Because supramolecular dendrimers with high quality and purity have potential for drug delivery, biosensor, and catalysis applications, many strategies have been explored for synthesizing these types of materials [ 88 , 89 ]. Here we selected an example of self-assembly of silsequioxane-based dendrimers, because the solvent′s effect on the π‒π stacking, hydrogen bonding, and van der Waals interactions were investigated [ 90 ]. In methyl methacrylate, π‒π stacking of the dendrimer, as shown in Figure 6 a, resulted in formation of linear supramolecules.…”

[Paper] Stabilization Effect of Self-Assembly Dendrimer Doped Cholesteric Liquid Crystal on Helical Structure

“…According to the related literature, this material has an interesting ability: nano-sized fibril structure was formed and enables reconstruction of its structure even if such structure was destroyed. 16) . The molecular structure of POSS-Lys is shown in Fig.…”