Structural and free volume characterization of sol–gel organic–inorganic hybrids, obtained by co‐condensation of two ureasilicate stoichiometric precursors

Abstract

In this study two hybrid organic-inorganic ureasilicate monomers with different length of polymer segments were chosen for preparation of sol-gel material that includes two moieties blended on the molecular scale. The first monomer was obtained by crosslinking a double terminated polyoxyalkyleneamine with an isocyanate modified silicone ethoxide and the second oneby crosslinking between the isocyanate modified silicone ethoxide with an amino modified silicone ethoxide. Sol-gel route was applied for transformation of the liquid monomer blends in transparent materials with varying degree of rigidity. The prepared samples were characterized by small-angle X-ray scattering, Fouriertransform infrared spectroscopy, positron annihilation lifetime spectroscopy, and swelling experiments. The results demonstrate that the structure of the obtained materials could be tuned by a simple variation of molar fraction ratio between these two monomers. This makes it possible to obtain nanostructured materials with predictable properties.

Pickering emulsion templated strategy in composite aerogels with hierarchical porous structure improves thermal insulation and diphenylamine adsorption

“…Aerogels are extremely porous and light materials with interesting properties including thermal insulation, adsorption and separation 1–3 . They exhibit a three‐dimensional (3D) network structure that can be fabricated from inorganic, 4–8 organic 9–11 and inorganic/organic hybrids 12–16 . Since cellulose is an eco‐friendly, renewable, and economic biopolymers, nanocelluloses (NCs)‐based areogels have received significant attention 17–19 …”

“…[1][2][3] They exhibit a threedimensional (3D) network structure that can be fabricated from inorganic, 4-8 organic [9][10][11] and inorganic/organic hybrids. [12][13][14][15][16] Since cellulose is an eco-friendly, renewable, and economic biopolymers, nanocelluloses (NCs)-based areogels have received significant attention. [17][18][19] Nonetheless, pure NCs aerogels have limited functionality and generally tend to disintegrate in water, thus this reduces their application potential.…”

Synthesis and characterization of polyimidazolium species on silica nanoparticles: Study on cytotoxicity and removal of nitrate from water

“…Reinforcement of polymers using organic and inorganic materials is very common and by adding a small percentage of nanoparticles to a pure polymer, the properties of the polymer are significantly improved. 3,[24][25][26][27][28] Nanocomposites with special properties are used in application such as films, fibers, electrical application, drug delivery systems, home appliances, constructions, fire retardant plastics, and water purification, etc. [30][31][32] The present research reports an efficient method for a set of new polyimidazolium compounds obtained through modifying the Debus-Radziszewski reaction.…”

“…Polymer nanocomposites generally have high strength, thermal stability, electrical conductivity, chemical resistance, and lightweight. Reinforcement of polymers using organic and inorganic materials is very common and by adding a small percentage of nanoparticles to a pure polymer, the properties of the polymer are significantly improved 3,24–28 . Nanocomposites with special properties are used in application such as films, fibers, electrical application, drug delivery systems, home appliances, constructions, fire retardant plastics, and water purification, etc 30–32 …”

Synthesis and Selective Au(III) Adsorption of Ureido Polymers Containing Large Repeating Rings

“…Heavy metal ion pollution in water has caused serious ecological problems, and how to deal with water pollution is a hot issue. , A lot of methods are studied to remove heavy metal ions from the wastewater. Among the techniques, various functional polymers are used as adsorbents for heavy metal ions, which are to be scavenged due to the preciousness or toxicity. − Polymers containing macrocyclic rings have attracted significant attention because of their unique properties to capture specific heavy metal ions, − such as cadmium, lead, mercury, copper, silver metal ions, and so forth. To tune the ability of binding metal ions, proper designs of the functional groups and the ring’s size are necessary, as for crown ethers, , porphyrin, , and cyclodextrins. , Polymers containing large rings can be synthesized by (1) cyclopolymerization, − (2) polymerization of monomers with macrocyclic structures, and (3) modification of polymers using large-ring molecules. , In all cases, the simple and efficient introduction of macrocyclic structures remains a challenge.…”