Leach-Proof Sol–Gel Microcapsules as Curing Agents for One-Pot Thermosetting Resins

2013 ◽  
Vol 1 (12) ◽  
pp. 1572-1579 ◽  
Author(s):  
Rosaria Ciriminna ◽  
Marzia Sciortino ◽  
Aster de Schrijver ◽  
Delphine Desplantier-Giscard ◽  
François Béland ◽  
...  
2019 ◽  
Author(s):  
Valentin Smeets ◽  
Ludivine van den Biggelaar ◽  
Tarek Barakat ◽  
Eric M. Gaigneaux ◽  
Damien Debecker

Self-standing macrocellular titanosilicate monolith foams are obtained using a one-pot sol-gel route and show excellent performance in the epoxidation of cyclohexene. Thanks to the High Internal Phase Emulsion (HIPE) templating method, the materials feature a high void fraction, a hierarchically porous texture and good mechanical strength. Highly dispersed Ti species can be incorporated in tetrahedral coordination the silica matrix. These characteristics allow the obtained ‘SiTi(HIPE)’ materials to reach high catalytic turnover in the epoxidation of cyclohexene. The monoliths can advantageously be used to run the reaction in continuous flow mode.<br>


2018 ◽  
Vol 24 (19) ◽  
pp. 4982-4990 ◽  
Author(s):  
Angel Manuel Escamilla-Pérez ◽  
Nicolas Louvain ◽  
Bruno Boury ◽  
Nicolas Brun ◽  
P. Hubert Mutin

Nanomaterials ◽  
2021 ◽  
Vol 12 (1) ◽  
pp. 149
Author(s):  
Enrico Paradisi ◽  
Roberto Rosa ◽  
Giovanni Baldi ◽  
Valentina Dami ◽  
Andrea Cioni ◽  
...  

A new method for fast and simple synthesis of crystalline TiO2 nanoparticles with photocatalytic activity was developed by carrying out a classic sol–gel reaction directly under vacuum. The use of microwaves for fast heating of the reaction medium further reduces synthesis times. When the solvent is completely removed by vacuum, the product is obtained in the form of a powder that can be easily redispersed in water to yield a stable nanoparticle suspension, exhibiting a comparable photocatalytic activity with respect to a commercial product. The present methodology can, therefore, be considered a process intensification procedure for the production of nanotitania.


2016 ◽  
Vol 2 (1) ◽  
pp. 23-30 ◽  
Author(s):  
O.S.N. Ghosh ◽  
◽  
S. Gayathri ◽  
D. Alagarasan ◽  
K.V.P. Kumar ◽  
...  

2019 ◽  
Author(s):  
Roberto Köferstein

BaTiO3-MgFe2O4 composites (30 wt.% MgFe2O4) with a small addition of BaGeO3 as a sintering additive were synthesized by a one-pot Pechini-like sol-gel process. Nano-crystalline composite powders with a crystallite size of about 10 nm were obtained after reaction at 700 °C for 1 h. Magnetic investigations suggest that the nano-powder is in its superparamagnetic state at room temperature. The addition of BaGeO3 leads to an improved sintering behaviour. DTA measurements reveal the formation of a liquid phase at 1164(3) °C. Dense ceramic bodies (relative density &gt; 90 %) were obtained after sintering for 1 h at 1150 °C. SEM investigations prove a 0-3 connectivity and show that the addition of BaGeO3 promotes the grain growth leading to particles up to 4 μm. In contrast, fine-grained composite ceramics with smaller particles up to 230 nm were obtained after a two-step sintering process. Magnetic measurements indicate a ferrimagnetic behaviour with coercivity values up to 70 Oe depending on the sintering procedure. Furthermore, addition of BaGeO3 results in an increase of the relative permittivity, whereas the dissipation factor slightly decreases.


2018 ◽  
Vol 5 (1) ◽  
pp. 49-58 ◽  
Author(s):  
Yu.S. Demidova ◽  
I.L. Simakova ◽  
E.V. Suslov ◽  
K.P. Volcho ◽  
N.F. Salakhutdinov ◽  
...  

Abstract In the current work gold catalysts supported on both commercial oxides and oxides synthesized by the sol-gel method were used for the one-pot alcohol amination of myrtenol. In general, utilization of metal oxides synthesized by the sol-gel method as the gold catalyst support enhanced the knowledge regarding key parameters determining catalytic behavior. Synthesized alumina was characterized by stronger acid sites favoring primary amine accumulation on the catalyst surface, as compared to the commercial oxide. Utilization of mixed metal oxides synthesized by the sol-gel method resulted in the non-additive behavior of different oxides enhancing the catalytic activity. Introduction of ceria into alumina modified the support basicity resulting in more efficient alcohol activation.


2020 ◽  
Vol 96 (1) ◽  
pp. 236-246
Author(s):  
Marta Gallo ◽  
Fabio Giudice ◽  
Mauro Banchero ◽  
Silvia Ronchetti ◽  
Luigi Manna ◽  
...  

Abstract Curcumin is a natural active principle with antioxidant, antibacterial and anti-inflammatory properties. Its use is limited by a low water solubility and fast degradation rate, which hinder its bioavailability. To overcome this problem, curcumin can be delivered through a carrier, which protects the drug molecule and enhances its pharmacological effects. The present work proposes a simple one-pot sol–gel synthesis to obtain a hybrid carrier for curcumin delivery. The hybrid consists of a mesostructured matrix of amorphous silica, which stabilizes the carrier, and hexadecyltrimethylammonium (CTA), a surfactant where curcumin is dissolved to increase its water solubility. The carrier was characterized in terms of morphology (FESEM), physicochemical properties (XRD, FTIR, UV spectroscopy) and release capability in pseudo-physiological solutions. Results show that curcumin molecules were entrapped, for the first time, in a silica-surfactant mesostructured hybrid carrier. The hybrid carrier successfully released curcumin in artificial sweat and in a phosphate buffer saline solution, so confirming its efficacy in increasing curcumin water solubility. The proposed drug release mechanism relies on the degradation of the carrier, which involves the concurrent release of silicon. This suggests strong potentialities for topical administration applications, since curcumin is effective against many dermal diseases while silicon is beneficial to the skin.


2019 ◽  
Vol 54 (13) ◽  
pp. 9553-9564 ◽  
Author(s):  
Maria Laura Ligabue ◽  
Fabio Terzi ◽  
Chiara Zanardi ◽  
Gigliola Lusvardi

Materials ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 475
Author(s):  
Yabin Wei ◽  
Shuangling Jin ◽  
Rui Zhang ◽  
Weifeng Li ◽  
Jiangcan Wang ◽  
...  

Novel Mn–Ce–Ti–O composite aerogels with large mesopore size were prepared via a one-pot sol–gel method by using propylene oxide as a network gel inducer and ethyl acetoacetate as a complexing agent. The effect of calcination temperature (400, 500, 600, and 700 °C) on the NH3–selective catalytic reduction (SCR) performance of the obtained Mn–Ce–Ti–O composite aerogels was investigated. The results show that the Mn–Ce–Ti–O catalyst calcined at 600 °C exhibits the highest NH3–SCR activity and lowest apparent activation energy due to its most abundant Lewis acid sites and best reducibility. The NO conversion of the MCTO-600 catalyst maintains 100% at 200 °C in the presence of 100 ppm SO2, showing the superior resistance to SO2 poisoning as compared with the MnOx–CeO2–TiO2 catalysts reported the literature. This should be mainly attributed to its large mesopore sizes with an average pore size of 32 nm and abundant Lewis acid sites. The former fact facilitates the decomposition of NH4HSO4, and the latter fact reduces vapor pressure of NH3. The NH3–SCR process on the MCTO-600 catalyst follows both the Eley–Rideal (E–R) mechanism and the Langmuir–Hinshelwood (L–H) mechanism.


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