Generation of Melamine Polymer Condensates upon Hypergolic Ignition of Dicyanamide Ionic Liquids

Abstract

Die Reaktion von ionischen Flüssigkeiten mit Dicyanamid‐Ionen mit Salpetersäure hat eine hypergole Zündung und die Bildung eines stabilen Niederschlags zur Folge. Dieser besteht aus cyclischen Triazinen, darunter Melamin und seine Polymere wie Melam und Melem (siehe Schema). Diese Studie führt einen neuen Syntheseansatz für cyclische Azine ein, der hohe Temperaturen und Drücke umgeht.

Metallic Cobalt Encapsulated in Bamboo-Like and Nitrogen-Rich Carbonitride Nanotubes for Hydrogen Evolution Reaction

“…6,43 The released protons should be as a hydroxyl condensation reaction catalyst where the surface −NH 2 groups within C 3 N 4 nanosheets are substituted with the −OH groups. 44,45 Then, bulk pCN is exfoliated to form Co 2+ − N-doped carbon fiber (Co 2+ −NCF) composite after the introduction of Co 2+ ions solution and ultrasonic treatment, 17,46,47 where the chemical state of cobalt is verified with XPS characterization (Figure S11). The similar surface energy of water (102 mJ m −2 ) and C 3 N 4 (115 mJ m −2 ) and the easy formation of hydrogen bonds between them should facilitate the exfoliation of pCN.…”

Ionic Liquid Propellants: Future Fuels for Space Propulsion

“…Recent work has proven that, for the dicyanamide-based ionic liquids, the anion is responsible for inducing the ignition, while the cation may play only a secondary role in influencing the ID time. [25] Very recently, Zare et al reported that reaction between dicyanamidebased ILs (e.g., [EMIm]DCA) and WFNA always yielded a precipitate that is composed of cyclic triazines, including melamine and its polymers; [26] from which it could be deduced that about 25 % of ionic liquid was converted into the precipitate during the ignition. Evidence also showed that polymerization occurred even at lower concentration of reagents (e.g., the reaction of dicyanamide ILs with aqueous HNO 3 solution), when neither hypergolic ignition nor notable heating of the reaction mixture take place.…”

“…Structures and mechanisms for the formation of the species observed in the reaction between dicyanamide ILs and nitric acid. [26] www.chemeurj.org ILs and nitric acid also provides an interesting approach to facile, ambient synthesis of cyclic azines, which constitute the forefront of modern carbon nitride chemistry.…”

“… Structures and mechanisms for the formation of the species observed in the reaction between dicyanamide ILs and nitric acid 26…”

Ultrathin graphitic C3N4 nanofibers: Hydrolysis-driven top-down rapid synthesis and application as a novel fluorosensor for rapid, sensitive, and selective detection of Fe3+

“…g-C 3 N 4 is green, sustainable, and can be facilely synthesized in large scale with low cost by polycondensation of various carbon and nitrogen-containing organic precursors [3][4][5]. In recent years, g-C 3 N 4 has been widely used in photocatalysis and photovoltaics [6][7][8][9][10][11][12], bioimaging [13], sensing [14][15][16][17][18][19][20], and electrocatalytic oxygen reduction [21][22][23][24], etc.…”