Results 61 to 70 of about 10,860 (230)

The Structure of Cyclized Polybutadiene

, 1958
Polybutadiene was cyclized with sulfuric acid under rather drastic conditions. The cyclization was confirmed by the decrease of unsaturation and the change of physical properties. The low degree of unsaturation of cyclized polybutadiene, as determined by
J. Reid Shelton, Lieng-huang Lee
core   +1 more source

Viscometric study of high-cis polybutadiene in toluene solution

Journal of the Brazilian Chemical Society, 2006
Viscometric measurements, in toluene solution at 30 ºC, were performed with high-cis polybutadiene synthesized by neodymium based catalyst. Six different equations were used to calculate intrinsic viscosities and viscosimetric constant values: Huggins ...
Mello Ivana L., Delpech Marcia C., Coutinho Fernanda M. B., Albino Fernanda F. M.   +3 more
doaj  

Evaluation of UV-Curable Solid Rocket Propellants’ Properties for Advanced 3D Printing Technologies

Applied Sciences
Challenges in the traditional cast-and-cure manufacturing of composite solid propellants, such as the use of mandrels and the toxicity of curing agents, are being addressed through new propellant formulations and additive manufacturing techniques. Within
Filippo Masseni, Giacomo Tetti, Alessandra Zumbo, Camilla Noé, Giovanni Polizzi, Leonardo Stumpo, Andrea Ferrero, Dario Pastrone   +7 more
doaj   +1 more source

Rocket Solid Propellant Alternative Based on Ammonium Dinitramide [PDF]

INCAS Bulletin, 2017
Due to the continuous run for a green environment the current article proposes a new type of solid propellant based on the fairly new synthesized oxidizer, ammonium dinitramide (ADN).
Grigore CICAN, Alexandru-Daniel MITRACHE
doaj   +1 more source

Gold Nanoparticles Supported on Poly(Phenylene Oxide) as Selective and Versatile Catalyst for Hydroamination of Arylacetylenes with Anilines

European Journal of Inorganic Chemistry, EarlyView.
Gold nanoparticles supported on poly(2,6‐dimethyl‐1,4‐phenylene oxide) (AuNPs‐PPO) demonstrates efficient and selective hydroamination, with performance tuned by reaction conditions and substrate design. Electron‐withdrawing substituents enhance conversion while preserving E‐imine selectivity, highlighting a key role of intermediate acidity.
Marta Aversa, Salvatore Impemba, Alessia Giannattasio, Irene Contento, Enrico Berretti, Alessandro Lavacchi, Carmine Capacchione, Alfonso Grassi, Antonio Buonerba   +8 more
wiley   +1 more source

Infrared microspectroscopic study of the thermo-oxidative degradation of hydroxy-terminated polybutadiene/isophorone diisocyanate polyurethane rubber

, 2007
Hydroxy-terminated polybutadiene/isophorone diisocyanate (HTPB-IPDI) polyurethane rubber that was aged in air at elevated temperatures has been studied by infrared microspectroscopy.
Fredericks, Peter M., Celina, Mathew, Nagle, Dylan J., Rintoul, Llew   +3 more
core   +1 more source

Oxidation of unvulcanized, unstabilized polychloroprene: A kinetic study [PDF]

, 2014
Thermal oxidation in air at atmospheric pressure, in the 80-140 °C temperature range and in oxygen at 100 °C in the 0.02-3 MPa pressure range, of unvulcanized, unstabilized, unfilled polychloroprene (CR) has been characterized using FTIR and chlorine ...
LE GAC, Pierre Yves, ROUX, Gérard, VERDU, Jacques, FAYOLLE, Bruno, DAVIES, Peter   +4 more
core   +1 more source

Experimental and simulation research on microscopic damage of HTPB propellant under tension-shear loading

AIP Advances, 2022
In order to study the influence of loading conditions on propellant mesoscopic failure morphology, scanning electron microscopy was carried out to observe the morphology of the failure section of a hydroxyl-terminated polybutadiene propellant under ...
Jia-yuan Cui, Hong-fu Qiang, Jia-xiang Wang   +2 more
doaj   +1 more source

Fabrication of Hydroxy-Terminated Polybutadiene with Piezoelectric Property by Functionalized Branch Chain Modification

Molecules, 2023
Hydroxyl-terminated polybutadiene (HTPB)-based piezoelectric polymer (m-HTPB) is prepared for the first time by functionalized branch chain modification strategy.
Bo Yuan, Guang Wang, Wenxue Tian, Li Zhou, Chunxiang Li   +4 more
doaj   +1 more source

Field‐Cycling NMR Relaxometry in Tire Elastomer Science

Magnetic Resonance in Chemistry, EarlyView.
Field‐cycling NMR relaxometry has established as an ideal tool to investigate multiscale polymer dynamics. Here, we review and discuss applications on elastomers and elastomer compounds of interest for the tire industry to obtain information on segmental dynamics and on polymer dynamics over different regimes as a function of chain length in polymer ...
Francesca Nardelli, Michele Pierigé, Elisa Carignani, Marco Geppi, Francesca Martini, Lucia Calucci   +5 more
wiley   +1 more source