RESUMEN
Herein, a series of novel sulfur-containing functionalized disiloxanes based on a low-cost and commercially available material, i.e., 1,3-bis(3-glycidoxypropyl)-1,1,3,3-tetramethyldisiloxane, and various thiol compounds were prepared by thiol-epoxy click reaction. It was found that both lithium hydroxide (LiOH) and tetrabutylammonium fluoride (TBAF) have high catalytic activity after optimizing the reaction condition, and the reaction can be carried out with high yields, excellent regioselectivity, mild reaction condition, and good tolerance of functional groups. These compounds exhibit excellent nonconventional fluorescence due to the formation of coordination bonds between Si atoms and heteroatoms (e.g., S or N) and can emit blue fluorescence upon ultraviolet (UV) irradiation. These results demonstrate that the thiol-epoxy click reaction could promisingly act as an efficient organosilicon synthetic methodology to construct various organosilicon materials with novel structures and functionality, and thus their application scope will be significantly expanded.
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Silanos , Compuestos de Sulfhidrilo , Compuestos de Sulfhidrilo/química , Fluorescencia , Resinas Epoxi , AzufreRESUMEN
The fabrication of amphiphobic materials requires a precise and complicated design, especially for 3D porous materials, and amphiphobic sponges have rarely been investigated. This paper describes the synthesis of a superhydrophobic and oleophobic silicone sponge (SS-F) by simply building hierarchical structures, that is, introducing a secondary structure on the pore walls of a hydrophobic and oleophilic silicone sponge. This simple and efficient synthesis method is based on the thiol-ene click reaction. The uniform structure, composition, and hierarchical structures of SS-F are confirmed. The results of the analyses show that the secondary microstructure improves liquid repellency, while the rough and porous surface design ensures durability. Thus, SS-F exhibits good stability, and the amphiphobicity of the surface could withstand scalpel cutting, cyclic compression, extreme temperatures of 250 and -196 °C for 5 h, and long-term storage in an ambient environment. Both its outer and inner surfaces show superhydrophobicity and oleophobicity, which restrict the ability of the adsorption of liquids, enabling its use in oil and water. The introduction of hierarchical structures paves a way for preparing other 3D porous materials.
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Siliconas , Agua , Adsorción , Vendajes , Interacciones Hidrofóbicas e HidrofílicasRESUMEN
Silicone sponge, which is nontoxic, highly flexible, insulated, and chemically inert, has great promise in the aerospace, electronics, and health care industries. However, the inherent surface properties and the harsh synthesis method limit its application. A super-amphiphilic 3D silicone sponge is designed by a thiol-ene click reaction for the first time. The sponge possesses high porosity, low density, excellent adsorption ability, and reusability for water, oil, emulsions, and Hg2+ or dyes or suspended solids in them. The sponge can selectively adsorb a very high amount (941.3 mg g-1 ) of Hg2+ from solutions (water, oil, emulsions) containing various ions at a nearly 100% removal efficiency. Cation dyes can also be selectively captured by the sponge. Furthermore, the sponge is designed as a filter element for a filtration system, and the content of the pollutants in the filtrate reaches drinkable levels after the Hg2+ and dye solutions are processed. The filter can be reused with almost unchanged filtration efficiency after a simple washing process. The successful treatment of actual/artificial polluted water proves its practical value.
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Contaminantes Ambientales , Purificación del Agua , Adsorción , Porosidad , SiliconasRESUMEN
Heck coupling reactions are introduced as an efficient method to prepare porous polymers. Novel inorganic-organic hybrid porous polymers (HPPs) were constructed via Heck coupling reactions from cubic functional polyhedral oligomeric silsesquioxanes (POSS), iodinated octaphenylsilsesquioxanes (OPS) and octavinylsilsesquioxanes (OVS) using Pd(OAc)2 /PPh3 as the catalyst. Here, two iodinated OPS were used, IOPS and p-I8 OPS. IOPS was a mixture with 90% octasubstituted OPS (I8 ) and some nonasubstituted OPS (I9 ), while p-I8 OPS was a nearly pure compound with ≥99% I8 and ≥93% para-substitution. IOPS and p-I8 OPS reacted with OVS to produce the porous materials HPP-1 and HPP-2, which exhibited comparable specific surface areas with SBET of 418 ± 20 m(2) g(-1) and 382 ± 20 m(2) g(-1) , respectively, with total pore volumes of 0.28 ± 0.01 cm(3) g(-1) and 0.23 ± 0.01 cm(3) g(-1) , respectively. HPP-1 showed a broader pore size distribution and possessed a more significant contribution from the mesopores, when compared with HPP-2, thereby indicating that IOPS may induce more disorder because of the geometrical asymmetry. HPP-1 and HPP-2 possessed moderate carbon dioxide uptakes of 134 and 124 cm(3) g(-1) at 1 bar at 195 K, making them promising candidates for CO2 capture and storage. The synthesized porous polymers may be easily post-functionalized using the retained ethenylene groups.