Glycidyl azide polymer (GAP)-based polyurethane is an ideal elastomeric matrix for high-energy, low-smoke, and insensitive solid propellants. As the skeleton structure of GAP propellants, changes in the structure and properties of GAP elastomers during aging lead to the deterioration of propellant performance (especially in relation to mechanical properties), which causes safety risks. A high-temperature-accelerated aging experiment (70 °C) on a GAP elastomer was conducted.
View Article and Find Full Text PDFHydroxyl-terminated polybutadiene (HTPB) is a flexible telechelic compound with a main chain containing a slightly cross-linked activated carbon-carbon double bond and a hydroxyl group at the end. Therefore, in this paper, HTPB was used as a terminal diol prepolymer, and sulfonate AAS and carboxylic acid DMPA were used as hydrophilic chain extenders to prepare low-temperature adaptive self-matting waterborne polyurethane (WPU). Due to the fact that the non-polar butene chain in the HTPB prepolymer cannot form a hydrogen bond with the urethane group, and the solubility parameter difference between the hard segment formed by the urethane group is large, the gap of between the soft and hard segments of the WPU increases by nearly 10 °C, with more obvious microphase separation.
View Article and Find Full Text PDFCu nanoparticles are more active catalytically than CuO nanoparticles, which have been widely studied as catalysts for organic synthesis, electrochemistry, and optics. However, Cu nanoparticles are easily agglomerated and oxidized in air. In this research, columnar, flower-like, bubble-like and teardrop-shaped Cu/GO nanocomposites were fabricated a water-solvent thermal method and high temperature calcination technique using deionized water (HO), methanol (CHOH), ethanol (CHCHOH) and ethylene glycol (EG) as the solvent, respectively.
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