Robust Silica–Agarose Composite Aerogels with Interpenetrating Network Structure by In Situ Sol–Gel Process

Abstract

Aerogels are three-dimensional nanoporous materials with outstanding properties, especially great thermal insulation. Nevertheless, their extremely high brittleness restricts their practical application. Recently, although the mechanical properties of silica aerogels have been improved by regulating the precursor or introducing a polymer reinforcer, these preparation processes are usually tedious and time-consuming. The purpose of this study was to simplify the preparation process of these composite aerogels. A silicic acid solution treated with cation exchange resin was mixed with agarose (AG) to gel in situ, and then composite aerogels (CAs) with an interpenetrating network (IPN) structure were obtained by aging and supercritical CO2 fluid (SCF) drying. Compared to previous works, the presented CAs preparation process is briefer and more environmentally friendly. Moreover, the CAs exhibit a high specific surface area (420.5 m2/g), low thermal conductivity (28.9 mW m−1 K−1), excellent thermal insulation properties, and thermal stability. These results show that these CAs can be better used in thermal insulation.

Polymer-ceramic composites for bone challenging applications: Materials and manufacturing processes

“…94,95 This process allows for precise control over the size, shape, and content of the ceramic particles, resulting in composites with exceptional mechanical and thermal properties. 96,97 In addition, the study conducted by Dorozhkin provides further evidence of the successful application of the sol-gel technique, as demonstrated in the creation of a Titanium-HA composite with outstanding mechanical qualities and good biocompatibility. 66…”

Characterization and Fabrication of Xerogel Polymeric Nanocomposites and Multifunctional Applications

“…XG is a porous, architectured material emanating from varying drying strategies of wet gels . Thus, the enchanting and peculiar attributes of these porous materials are garnered from the peculiar exibility as well as resilience of the sol-gel fabrication procedure, garnered in synergy with either ambient drying (X-G) or supercritically a liated drying (A-G) [81][82][83][84][85][86][87][88][89][90][91][92][93][94][95][96][97][98][99][100]. As already elucidated, these substrates have been fabricated from varying precursors, like carbon, silica, and biopolymeric entities and possessing differing biological, physical, chemical, and mechanical, attributes, relative to varying parameters, including precursoral substrates, solvent medium, as well as drying parameters [101][102][103][104][105][106][107][108][109][110][111][112][113][114][115][116][117][118][119][120].…”

Woven Agarose–Cellulose Composite Aerogel Fibers with Outstanding Radial Elasticity for Personal Thermal Management

“…Moreover, their low densities mean that they are lightweight, which makes them well-suited to personal thermal management. 19−21 Compared to two-and three-dimensional aerogels, 22,23 onedimensional aerogels have excellent flexibility and greater potential for personal thermal management applications. 24 However, traditional aerogel materials, such as silica aerogels, are brittle and have poor mechanical properties due to their pearl-necklace-like skeleton structures, which makes it difficult to fabricate one-dimensional aerogel fibers.…”