JOURNAL OF CHEMICAL AND ENGINEERING DATA
·
2024
·
IF 2
Yanfei Sun,Yuan Gao,Ziping Yin,Zuoxin Liu,Xianxiong Chen,Yu Zhang,Jun Luo
For solid-state energetic materials, it might be able to exist in different crystal structures, which is well-known as polymorphism. Different polymorphs of the crystals exhibit different physiochemical properties, such as solubility, dissolution rate, morphology, etc. In this work, the solid–liquid phase equilibrium of 1,3,5,7-tetranitro-1,3,5,7-tetraazacyclooctane form α (α-HMX) over various temperature ranges (298.15 to 358.15 K) was experimentally determined using the dynamic method in 12 pure solvents, including acetone, pyridine, acetic acid, 2-butanone, cyclopentanone, acetonitrile, methyl acetate, ethyl acetate, isopropyl acetate, ethyl acetoacetate, methyl propyl ketone, and dimethyl sulfoxide (DMSO), at atmospheric pressure. The experimental results indicate that the solubility of α-HMX increases with increasing temperature in all test solvents. The experimental solubility data were correlated with four thermodynamic models, which are the modified Apelblat equation, the λh equation, the Wilson model, and the NRTL model. In addition, the dissolution thermodynamic properties, such as the enthalpy, entropy, and Gibbs free energy change, were also calculated with the experimental data and NRTL model. All of these results lay the foundation for the study of preparation and phase transformation of different crystal forms of HMX and provide guidance for designing suitable crystallization methods in different solvents.
研究领域:
化学
·
材料科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Xue-Xue Zhang,Xing Zhang,Chi Zhang,Xu Zhao,Zhi-Jian Yang,Qi-Long Yan
It is challenging to balance the energy and sensitivity for the development of energetic materials (EMs). In this paper, the HMX crystals with improved energy density but lower sensitivity have been prepared by intercalation of triaminoguanidine-glyoxal crosslinked graphene oxide (GO-TAGP). The morphologies and structure of intercalated HMX crystals depend largely on the content of GO-TAGP. Notably, the presence of a higher percentage of GO-TAGP leads to a transition of HMX crystal structure to the γ-form. It has been shown that with the constraint of GO-TAGP, HMX crystals show a significant enhancement in energy content. With intercalated 3.7 wt% of GO-TAGP, the density of modified HMX increased to 1.93 g·cm −3 with higher heat of explosion (5421 J·g −1 ) and higher heat of formation (140.6 kJ·mol −1 ) than that of neat HMX (1.89 g·cm −3 , 5242J·g −1 and 75.8kJ·mol −1 ). Importantly, remarkably improved thermal stability of modified HMX have been achieved, disclosing an excluded polymorphic transition via DSC and the variable-temperature powder XRD technique. In specific, the modified HMX with intercalated 1.0 wt% GO-TAGP exhibits superior safety performance with the impact energy increased to 26.5 J, even 780 % higher than pristine HMX (3 J). The detonation performance of as-modified HMX was tested, achieving an enhanced detonation velocity of 9254 m·s −1 , whereas that of raw HMX is only 9010 m·s −1 . This approach could offer an efficient strategy to enhance the energy content of HMX with significantly improved thermal stability and safety performance.
研究领域:
材料科学
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化学工程
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产品关联
DOI
高影响因子
PROPELLANTS EXPLOSIVES PYROTECHNICS
·
2021
·Vol. 46
·期 5
·751-757
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IF 1.887
Shuyi Duan,Dehai Wang,Quanping Jiang,Chun Xiao,Huihui Liu,Ya Guo,Shangbin Li,Qing Zhu
Polydopamine surface coating shows the capability to improve the adhesive properties as well as mechanical stabilities of energetic materials, which is highly desired for the development of insensitive munitions. However, the slow polymerization process of dopamine makes the coating process time-consuming and uneconomic. Herein, an oxidant-accelerated strategy was demonstrated to obtain fast polymerization kinetics of dopamine for the surface modification of HMX crystals. Upon the addition of oxidant, PDA was able to form surface layer of HMX particles within 5 min without changing the shape and polymorph of HMX crystals. The PDA coating showed the ability to improve the wettability of HMX, contributing to its abundant active groups. Moreover, the mechanical stability of PDA on HMX (HMX@PDA) samples was improved accompany with the increasing coating time, and the friction explosion probability and drop height of 300 s treated sample were 40 % and 64 cm, respectively. The detonation velocity was also measured, which showed that the effect of PDA coating on the detonation velocity of HMX was not significant. More importantly, our protocol showed the capability to fabricate HMX@PDA with different particle sizes on a large scale, satisfying the application demands of insensitive high explosives.
研究领域:
材料科学
·
爆炸物化学
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产品关联
DOI
高影响因子