Binary Crystallized Supramolecular Aerogels Derived from Host–Guest Inclusion Complexes

Abstract

Aerogels with low density and high porosity show outstanding properties such as large surface area and low thermal and acoustic conductivity. However, great challenges remain to convert hydrophilic polymer based hydrogels to corresponding aerogels. Here, we report a structurally new type of aerogels, supramolecular aerogels (SMAs), derived from supramolecular hydrogels formed by self-assembling of poly(ethylene glycol) and α-/γ-cyclodextrin. The SMAs posses a characteristic binary crystallized nanosheet structure due to their supramolecular cross-linking nature, and their specific surface areas and nanosheet structures are tunable. Furthermore, we demonstrated application of the aerogels as solid-solid phase change materials with tunable latent heat, reversible melting-crystallization cycle while keeping the microstructure of the SMAs unchanged.

Recyclable Nanoporous Materials with Ordered Tunnels Self‐Assembled from α‐ and γ‐Cyclodextrins

“…Porous materials, such as covalent organic frameworks (COF), [1,2] Metal-organic frameworks (MOF), [3,4] zeolites, [5,6] mesoporous silica, [7,8] aerogels, [9][10][11] and sponges, [12,13] have received considerable attentions in recent years due to their crucial applications in gas storage, absorption, separation, catalysis, sensing, energy, thermal insulation, and biomedicine etc. The physical properties and applications of the porous materials mostly rely on their pore parameters, [14,15] such as pore size, pore volume, porosity, regularity, and dispersity, [16][17][18] and can be tuned by different synthesis methods.…”

Superflexible Multifunctional Polyvinylpolydimethylsiloxane‐Based Aerogels as Efficient Absorbents, Thermal Superinsulators, and Strain Sensors

“…Thed egree of polymerization (n)o fP VDMMS is as high as 91. There is no peak or absorption band corresponding to vinyl groups observed in the 29 Si CP/MAS NMR (Figure 2a) or FTIR ( Figure S1) spectra, indicating the high conversion of PVDMMS and PVDMMS/PVMDMS.…”

“…However,t raditional aerogels are usually dried via costly supercritical drying (SCD) and exhibit low mechanical strength because of their intrinsically fragile/brittle networks,w hich need to be addressed before their practical applications.To overcome the costly drying process and brittleness, many efforts have been made to lower the cost by ambient pressure drying (APD), [23] freeze drying (FD) [22] and vacuum drying (VD), [24] and reinforce the aerogels by av ariety of methods.C ross-linking of aerogels with organic polymers is aw idely used method to reinforce the aerogels but usually results in lower porosity and higher density that limit their applications. [25,26] Flexible polymer-based aerogels can be obtained from resorcinol-formaldehyde, [27] poly(vinyl alcohol), [28] and supramolecules, [29] and some of them exhibit good absorption of organic solvents/oils.A nother kind of aerogels based on biomass such as nanocellulose and chitosan with compressibility and bendability have been reported. [30,31] Owing to their highly porous nanostructure that is composed of nanofibers,t hey show excellent thermal insulation performances.B esides,a ssembly of nanofibers via as pecific method can give compressible and elastic cellular aerogels with high pressure-sensitivity and good absorption/separation properties.…”

Versatile Double-Cross-Linking Approach to Transparent, Machinable, Supercompressible, Highly Bendable Aerogel Thermal Superinsulators

“…[22][23][24] Unlike the polysiloxane-based organic-inorganic hybrid aerogels, however, they do not show elastic recovery in response to compression and bending. It is reported that polymer-based aerogels such as supramolecular aerogel, 25 poly(vinyl alcohol)-based aerogel, 3 thermoelectric polymer aerogel 26 and resorcinol-formaldehyde aerogel 27 exhibit high mechanical strength or elasticity against compression. Nonetheless, almost all of them are mainly composed of macropores and are opaque in visible light region.…”