Results 111 to 120 of about 18,682 (226)

Préparation et caractérisation de nouveaux matériaux avancés pour l'énergie : synthèse et optimisation du procédé [PDF]

La production de biodiesel à partir d'huiles usagées pourrait être considérée comme une alternative durable aux combustibles fossiles. Cependant, l'efficacité dépend souvent du type de catalyseur utilisé.
DENDOUGA, Bouthina
core   +1 more source

Insights into kinetics and reaction mechanism of acid-catalyzed transesterification synthesis of diethyl oxalate

Resources Chemicals and Materials
The catalytic performance of different acidic catalysts for diethyl oxalate synthesis from the one-step transesterification of dimethyl oxalate and ethanol was evaluated.
Naiwen Zhang, Rui Xia, Siyu Wan, Xinyang Xiong, Jinggang Zhao, Jun Zhou, Lei Shi   +6 more
doaj   +1 more source

Polycarbonate Vitrimers and Dynamic Co‐Networks From Epoxide/Carbon Dioxide Copolymerization

Macromolecular Rapid Communications, EarlyView.
This work demonstrates how CO2‐derived poly(propylene carbonate) and poly(cyclohexene carbonate) backbones influence vitrimer thermo‐mechanical behavior. By tuning backbone composition, epoxide crosslinker chemistry and blend ratios, the crosslinked materials span a wide property window, from highly extensible to stiff, glassy networks, establishing an
Satej S. Joshi, Sophia Aracri, Mark D. Foster, James M. Eagan   +3 more
wiley   +1 more source

Fonctionnalisation chimique du bois par transesterification des esters d'enol

, 2020
Au cours de cette étude, une méthode inédite de fonctionnalisation chimique de la matière lignocellulosique a été développée. Des groupes acyles de taille et de fonctionnalité variées ont ainsi été greffés à l’intérieur du bois, grâce à une réaction de ...
JEBRANE, Mohamed
core  

Chemically and Mechanically Recyclable Polyolefins Incorporating Covalent Adaptable Networks

Macromolecular Rapid Communications, EarlyView.
Low‐molecular‐weight polypropylene is converted into a crosslinked polyolefin containing a covalently adaptable network. The semicrystalline material remains melt‐processable and mechanically recyclable. Its thermal and mechanical properties are comparable to commercial polyolefins.
Andrii Tiiara, Bernadine Daichendt, Sergiy Minko, Olga Kuksenok, Igor Luzinov   +4 more
wiley   +1 more source

Thiolate Salt Mediated Dynamic Silyl Ether Exchanges for Polymer Network Design and Deconstruction

Macromolecular Rapid Communications, EarlyView.
This work introduces thiolate salts as mediators for dynamic silyl ether exchange. This platform enables the synthesis of reprocessable covalent adaptable polymer networks (CANs) and allows for sterically controlled, and tunable deconstruction of silyl ether‐containing thermosets.
Pierce T. Bombard, Andrew D. Vargo, Henry P. Chesley‐Vogels, Georgios Tarasidis, Elise C. Desjarlais, Truman K. Sandy, Harry E. Touloukian, Dmytro Davydenko, Jennifer C. Vo, Bassil M. El‐Zaatari   +9 more
wiley   +1 more source

Étude des propriétés de surface et des propriétés rhéologiques des mélanges polymères thermotropes [PDF]

, 2001
Compatibilité et adhérence -- Effet de la réaction de transestérification dans les mélanges contenant des polyesters -- Cristaux liquides polymères -- Aspects généraux du comportement des cristaux liquides liquides polymères thermotropes (CLPT ...
Tovar Hernández, Maria Gabriela
core  

Rheological Assessment of Polymer Melts and Networks: From Degradation to Recyclability

Macromolecular Rapid Communications, EarlyView.
Rheology provides a powerful analytic tool for tracking polymer degradation and structural evolution across manufacturing, service, and recycling. Linear and nonlinear rheological techniques reveal changes in molecular architecture, network stability, and processing history.
Haocong Shi, Chongkai Zhao, Zaheer ul Haq, Shifeng Wang, Chaoying Wan   +4 more
wiley   +1 more source

Engineered alcohol oxidases catalyse transesterification in aqueous media without competing hydrolysis

Nature Communications
Transesterification reactions are fundamental transformations in organic chemistry, yet performing them in aqueous media is challenging because of the competing hydrolysis reaction.
Bin Wu, Yunjian Ma, Chenhao Feng, Limei Ren, Chiara Domestici, Yutong Wang, Thomas Hilberath, Ulf Hanefeld, Evgeny A. Pidko, Frank Hollmann, Yonghua Wang   +10 more
doaj   +1 more source

Analysis of Carbohydrates and Glycoconjugates by Matrix‐Assisted Laser Desorption/Ionization Mass Spectrometry: An Update for 2023–2024

Mass Spectrometry Reviews, EarlyView.
ABSTRACT The use of MALDI mass spectrometry for the analysis of carbohydrates and glycoconjugates is a well‐established technique and this comprehensive review is the twelfth update of the original article published in 1999 and brings coverage of the literature to the end of 2024.
David J. Harvey
wiley   +1 more source