Morphology and thermal properties relationship in poly(p-dioxanone)/layered double hydroxides nanocomposites

2010 ◽  
Vol 288 (7) ◽  
pp. 809-818 ◽  
Author(s):  
Manuela Zubitur ◽  
Agurtzane Mugica ◽  
Javier Areizaga ◽  
Milagros Cortázar
Keyword(s):  
Thermal Properties ◽  
Layered Double Hydroxides ◽  
Double Hydroxides

Structural and thermal properties of polystyrene nanocomposites containing hydrophilic and hydrophobic layered double hydroxides

2013 ◽  
Vol 77-78 ◽  
pp. 46-51 ◽  
Author(s):  
Ahmed M. Youssef ◽  
Tamás Bujdosó ◽  
Viktória Hornok ◽  
Szilvia Papp ◽  
Abou el Fotouh Abdel Hakim ◽  
...  
Keyword(s):  
Thermal Properties ◽  
Layered Double Hydroxides ◽  
Double Hydroxides

Microwaves and layered double hydroxides: A smooth understanding

2009 ◽  
Vol 81 (8) ◽  
pp. 1459-1471 ◽  
Author(s):  
Patricia Benito ◽  
Francisco M. Labajos ◽  
Vicente Rives
Keyword(s):  
Particle Size ◽  
Thermal Properties ◽  
Particle Size Distribution ◽  
Hydrothermal Treatment ◽  
Layered Double Hydroxides ◽  
Urea Hydrolysis ◽  
Microwave Hydrothermal ◽  
Noticeable Reduction ◽  
Time Required ◽  
Double Hydroxides

Microwave-hydrothermal treatment (MWHT), a modification of conventional hydrothermal treatment, has been used during post-treatment of different layered double hydroxides (LDHs). In some cases, microwaves (MWs) have been used simultaneously with urea hydrolysis or for reconstruction of the LDH structure. The main advantages of replacing the conventional furnaces by MW ovens are a noticeable reduction in the time required to complete the process to obtain well-crystallized materials, and modification of their particle size distribution and textural and thermal properties. MW radiation leads to an increase in the rate of urea hydrolysis and consequently to fast precipitation of LDHs. Finally, the memory effect of Ni,Al-based LDHs is also improved.

scholarly journals Thermal Properties of Lauric- and Stearic Acid Intercalated Layered Double Hydroxides

2010 ◽  
Vol 521 (1) ◽  
pp. 168-178 ◽  
Author(s):  
Walter Wilhelm Focke ◽  
Nontete Susan Nhlapo ◽  
Lumbidzani Moyo ◽  
Sabine Marie Charlotte Verryn
Keyword(s):  
Thermal Properties ◽  
Stearic Acid ◽  
Layered Double Hydroxides ◽  
Double Hydroxides

Acceptorless amine dehydrogenation and transamination using Pd-doped layered double hydroxides

2018 ◽  
Author(s):  
Diana Ainembabazi ◽  
Nan An ◽  
Jinesh Manayil ◽  
Kare Wilson ◽  
Adam Lee ◽  
...  
Keyword(s):  
Layered Double Hydroxides ◽  
Oxidation States ◽  
Secondary Amines ◽  
Primary Amines ◽  
Acid Dissolution ◽  
Oxidative Amination ◽  
Strong Function ◽  
Excellent Activity ◽  
High Yields ◽  
Double Hydroxides

<div> <p>The synthesis, characterization, and activity of Pd-doped layered double hydroxides (Pd-LDHs) for for acceptorless amine dehydrogenation is reported. These multifunctional catalysts comprise Brønsted basic and Lewis acidic surface sites that stabilize Pd species in 0, 2+, and 4+ oxidation states. Pd speciation and corresponding cataytic performance is a strong function of metal loading. Excellent activity is observed for the oxidative transamination of primary amines and acceptorless dehydrogenation of secondary amines to secondary imines using a low Pd loading (0.5 mol%), without the need for oxidants. N-heterocycles, such as indoline, 1,2,3,4-tetrahydroquinoline, and piperidine, are dehydrogenated to the corresponding aromatics with high yields. The relative yields of secondary imines are proportional to the calculated free energy of reaction, while yields for oxidative amination correlate with the electrophilicity of primary imine intermediates. Reversible amine dehydrogenation and imine hydrogenation determine the relative imine:amine selectivity. Poisoning tests evidence that Pd-LDHs operate heterogeneously, with negligible metal leaching; catalysts can be regenerated by acid dissolution and re-precipitation.</p> </div> <br>

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