A series of ultrahigh molecular weight polyethylenes with viscosity-average molecular weights in the range of 1.6⁻5.6 × 10⁶ have been prepared by using a novel Ziegler⁻Natta-type catalytic system-TiCl₄/2,2'-dimethoxy-1,1'-binaphthalene/Et₃Al₂Cl₃/Bu₂Mg at different temperatures () in the range between 10 and 70 °C in toluene. The morphology of the nascent reactor powders has been studied by scanning electron microscopy, wide-angle X-ray diffraction, and the DSC melting behavior. Polymers are suitable for the modern processing methods-the solvent-free solid-state formation of super high-strength (tensile strength over 1.8⁻2.5 GPa) and high-modulus (elastic modulus up to 136 GPa) oriented film tapes. With decrease of , the drawability of the reactor powders increased significantly.
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http://dx.doi.org/10.3390/polym10111281 | DOI Listing |
Chemistry
January 2025
Université de Montréal, FRQNT Centre in Green Chemistry and Catalysis, Centre for Continuous Flow Synthesis, Department of Chemistry, 1375 av. Thérèse Lavoie-Roux, Montréal, QC, H2V 0B3, Canada.
The pentafluorosulfanyl (SF-) group has been the subject of a surge of interest in the past decade, but there is still little practicality associated with its synthesis and installation. Herein is reported the first continuous flow synthesis of pentafluorosulfanyl chloride (SFCl), the most common reagent for the synthesis of SF-substituted compounds. The synthesis is based on inexpensive and easy-to-handle reagents: sulfur powder (S), trichloroisocyanuric acid (TCCA) and potassium fluoride (KF).
View Article and Find Full Text PDFInt J Pharm
January 2025
School of Mechanical and Mechatronic Engineering, University of Technology Sydney (UTS), 15 Broadway, Ultimo, New South Wales 2007, Australia. Electronic address:
Nanocarrier-based dry powders for lung disease treatment are crucial, with in vitro and in silico research being pivotal to their success. This study introduces a method for creating Tiotropium-bromide liposomal inhalation dry powder, termed "Trojan-particles," utilizing thin-film hydration and spray-drying with lactose-arginine carriers. Encapsulating tiotropium-bromide in nanoliposomes enhances lung treatment via liposomes' unique features.
View Article and Find Full Text PDFMaterials (Basel)
December 2024
COMTES FHT a.s., Prumyslova 995, 334 41 Dobrany, Czech Republic.
One of the concepts behind Generation IV reactors is a molten salt coolant system, where the materials for the reactor itself and for the primary and secondary circuit components are subjected to extreme chemical and thermal stresses. Due to the unavailability of these materials, a nickel-molybdenum alloy known as MoNiCr has been developed in the Czech Republic. This paper discusses the manufacturing process for the MoNiCr alloy, covering conventional casting technology, forming, powder atomization, additive manufacturing (AM) using the directed energy deposition (DED-LB) process, and final heat treatment.
View Article and Find Full Text PDFChemosphere
January 2025
Department of Civil and Environmental Engineering, University of Massachusetts Lowell, Massachusetts, United States. Electronic address:
There is significant interest in monitoring abiotic decomposition of chlorinated solvents at contaminated sites due to large uncertainties regarding the rates of abiotic attenuation of trichloroethylene (TCE) and perchloroethylene (PCE) under field conditions. In this study, an innovative passive sampling tool was developed to quantify acetylene, a characteristic product of abiotic reduction of TCE or PCE, in groundwater. The sampling mechanism is based on the highly specific and facile click reaction between acetylene and an azide compound to form a biologically and chemically stable triazole product.
View Article and Find Full Text PDFACS Appl Mater Interfaces
January 2025
Department of Chemical and Biomolecular Engineering, National University of Singapore, Singapore 117580, Singapore.
Hydrate-based carbon capture and storage (HBCS) is a sustainable and promising approach to combating global warming by utilizing water, which is a ubiquitous resource. Here, we report a comprehensive study of CO hydrate formation in dry water (DW), a water-in-air dispersion confined in silica particles, for improving the kinetics of hydrate growth. Utilizing a combination of a home-built high-pressure reactor, in situ Raman spectroscopy, and powder X-ray diffraction (PXRD), we elucidate the crystal structure, growth dynamics, and morphology of CO hydrates formed in DW, with and without the kinetic hydrate promoter, l-tryptophan.
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