Regioselective Synthesis of Eight-Armed Cyclosiloxane Amphiphile for Functional 2D and 3D Assembly Motifs

Abstract

A crystalline tetramethylcyclotetrasiloxane (TMCS)-derived amphiphile was regioselectively synthesized with eight peripheral hydrophilic amide groups and hydrophobic dodecyl chains by Pt(0)-catalyzed hydrosilylation and amidation reactions. The as-synthesized materials showed ordered lamellar structure formation in the powder form. It also exhibits superior two-dimensional (2D) monolayer formation properties at the air-water interface with unexpectedly high collapse surface pressure and elastic modulus. The monolayers act as two-dimensional building blocks with finely controllable thickness on a several nanometer scale irrespective of the substrate type and properties. The amphiphile forms nanofibers spontaneously by good-poor solvent strategies, which contributes to porous three-dimensional (3D) structures possessing superhydrophobic surface wettability.

Cyanostilbene‐Based AIEgen Smart Film: Optical Switching by Engineering Molecular Packing Structure and Molecular Conformation Through Thermal and Photoinduced Monotropic Phase Transition

“…The other weak halo at 2θ = 11.26° ( d = 0.78 nm) comes from the average distance between cyclosiloxanes. [ 43,44,46 ] Below T i , a single diffraction peak newly appears at 2θ = 3.35° ( d = 2.63 nm) without noticeable high‐order diffraction peaks. In a high‐angle region, the scattering halo is slightly shifted to a lower angle and sharpened, which is attributed to the lateral molecular packing between cyanostilbene mesogens.…”

“…For the development of smart organic materials with target properties, many material scientists and engineers have tried to understand the thermodynamic and kinetic relationships between chemical structure, molecular packing structure and for meso-nanostructure, organic-inorganic hybrids, and functional amphiphiles. [39][40][41][42][43][44][45] In this context, there have been several reports about the synthesis and application of cyclosiloxanebased molecules, but the thermodynamic and kinetic relationships between the chemical structure, molecular packing structure, and resulting material properties of cyclosiloxane-based functional molecules need to be further studied.…”

Low‐dielectric constant and viscosity tetrafunctional bio‐based epoxy resin containing cyclic siloxane blocks

“…The main reason is that the bond energy of Si O is greater than that of C C. During thermal oxidation, a protective layer rich in the Si O Si chain is formed on the surface of the silicon polymer, which reduces the impact on the interior of the polymer and makes it have a relatively high thermal decomposition temperature. 66,67 Besides, stronger intermolecular interactions of D4H further enhance the thermal stability of DEP-MHHPA and AGDEP-MHHPA samples.…”

Self-Assembly and Applications of Amphiphilic Hybrid POSS Copolymers

“…The structures vary depending on the type of substance used and the environment in which they are located [ 75 ]. Recently, there has been tremendous interest in hybridized amphiphilic polymers with POSS nanocages [ 76 , 77 , 78 , 79 ]. Thus, a variety of interesting studies have been conducted to develop new synthetic protocols and explore their self-assembly behavior.…”