Graphene-based Composites for the Thermal Decomposition of Energetic Materials

2021 ◽  
Vol 1027 ◽  
pp. 123-129
Author(s):  
Ya Hao Liu ◽  
Jian Zheng ◽  
Gui Bo Yu ◽  
Jing Qia ◽  
Quan Qun Xu ◽  
...  

Owing to its remarkable mechanical, electrical and thermal properties, graphene has been a hot area of composites research in the past decade, including the field of energetic materials. Graphene has been widely applied in enhancing the physical properties of energetic materials, such as solid composite propellants. Through the way of adding different forms of graphene into the matrix of solid propellants, their thermal decomposition performance can be effectively improved. In this paper, we reviewed the status and challenges of the application of graphene in the thermal decomposition of composite solid propellant. Moreover, the main preparation methods and material structures of graphene are reviewed. We can conclude that graphene and its derivatives can enhance the catalytic effect remarkably, which can be attributed to the large specific surface area of graphene that makes the uniformly dispersed catalyst particles and the more catalyst active sites. Meanwhile, graphene possesses the high thermal conductivity, making the rapider heat diffusion, which can promote the decomposition reactions of the energetic components in solid propellants. Graphene and catalyst work synergistically in their thermal decomposition. More than this, the main methods to improve the thermal decomposition of energetic components of composite propellants and their effects on decomposition temperature reduction are systematically summarized, respectively.

2021 ◽  
Author(s):  
pragnesh N Dave ◽  
Ruksana Sirach ◽  
Riddhi Thakkar ◽  
M P Deshpande

Abstract Less sensitive high energetic materials (HEMs) are explored as a potential replacement of highly sensitive HEMs in propellants, and explosive applications. More research have been devoted to improve the thermal decomposition of such a less sensitive HEMs. Nanosize Cobalt ferrite (CoF) has been successfully synthesized using the co-precipitation method. Synthesis of less sensitive HEM 3-nitro-2,4-dihydro-3H-1,2,4-triazol-5-one(NTO) and its size reduction using solvent-antisolvent method is successfully achieved. Effect of 5 % by weight CoF on the thermolysis of NTO and NTO with reduced size (r-NTO) has been studied using the simultaneous thermal analysis. Three isoconversional methods namely Flynn Ozawa Wall, Kissinger-Akahira-Sunose (KAS), and Starink are employed to evaluate the kinetic parameter of NTO, and r-NTO in the presence of CoF additive. It was found that both the addition of CoF as well as reducing size of NTO can decrease the thermal decomposition temperature of NTO, the later decreasing the thermal decomposition temperature to a good extent compared to former. However, the kinetic study using isoconversional methods suggested that in the presence of CoF additive, the activation energy of both NTO as well as n-NTO is increased.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Jichuan Zhang ◽  
Yongan Feng ◽  
Richard J. Staples ◽  
Jiaheng Zhang ◽  
Jean’ne M. Shreeve

AbstractOwing to its simple preparation and high oxygen content, nitroformate [−C(NO2)3, NF] is an extremely attractive oxidant component for propellants and explosives. However, the poor thermostability of NF-based derivatives has been an unconquerable barrier for more than 150 years, thus hindering its application. In this study, the first example of a nitrogen-rich hydrogen-bonded organic framework (HOF-NF) is designed and constructed through self-assembly in energetic materials, in which NF anions are trapped in pores of the resulting framework via the dual force of ionic and hydrogen bonds from the strengthened framework. These factors lead to the decomposition temperature of the resulting HOF-NF moiety being 200 °C, which exceeds the challenge of thermal stability over 180 °C for the first time among NF-based compounds. A large number of NF-based compounds with high stabilities and excellent properties can be designed and synthesized on the basis of this work.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jing Zhou ◽  
Li Ding ◽  
Yong Zhu ◽  
Bozhou Wang ◽  
Xiangzhi Li ◽  
...  

AbstractOrganic inner salt structures are ideal backbones for heat-resistant energetic materials and systematic studies towards the thermal properties of energetic organic inner salt structures are crucial to their applications. Herein, we report a comparative thermal research of two energetic organic inner salts with different tetraazapentalene backbones. Detailed thermal decomposition behaviors and kinetics were investigated through differential scanning calorimetry and thermogravimetric analysis (DSC-TG) methods, showing that the thermal stability of the inner salts is higher than most of the traditional heat-resistant energetic materials. Further studies towards the thermal decomposition mechanism were carried out through condensed-phase thermolysis/Fourier-transform infrared (in-situ FTIR) spectroscopy and the combination of differential scanning calorimetry-thermogravimetry-mass spectrometry-Fourier-transform infrared spectroscopy (DSC-TG-MS-FTIR) techniques. The experiment and calculation results prove that the arrangement of the inner salt backbones has great influence on the thermal decompositions of the corresponding energetic materials. The weak N4-N5 bond in “y-” pattern tetraazapentalene backbone lead to early decomposition process and the “z-” pattern tetraazapentalene backbone exhibits more concentrated decomposition behaviors.


Development ◽  
1986 ◽  
Vol 94 (1) ◽  
pp. 95-112
Author(s):  
Fiona Tuckett ◽  
Gillian M. Morriss-Kay

This paper forms part of our study of the extracellular matrix and its role in the morphogenesis of the brain during the period of neurulation in the rat embryo. Using indirect immunofluorescence with polyclonal antibodies, we present here a descriptive study of the distribution of the matrix glycoproteins fibronectin, laminin and entactin. The observed distribution of the fibronectin matrix implicates it in providing a structural element in several morphologically active sites; in addition our observations support the previously suggested involvement of fibronectin in the migration of neural crest cells. Entactin was present only in the basement membranes in conjunction with laminin which was not itself confined to these regions. Laminin was also identified within the mesenchymal extracellular matrix, and its general distribution confirms the previously documented role of laminin in maintaining epithelial structure and organization. No patterning in the distribution of these three glycoproteins could be correlated with the change in shape of the neural epithelium associated with either tube formation or neuromere morphogenesis.


2018 ◽  
Vol 38 ◽  
pp. 02019
Author(s):  
Yong-xin Zhao ◽  
Ying-qiang Zhang

Highly transparent silicone resin with self-crosslinking structure was prepared using phenyltrimethoxysilane, diphenyldimethoxysilane, 1,3,5,7-cyclotetra(methyl siloxane) and bisvinyltetramethyldisiloxane as main raw materials. The structure of silicone resin was determined by Fourier Transform Infrared Spectroscopy (FT-IR). The light transmittance was measured by UV-Vis spectroscopy. Thermogravimetric analysis (TGA) was used to study the thermal decomposition process. The microstructure of cured self-crosslinking silicone resin is more uniform, resulting in better light transmittance up to 100% in the range of 400nm ~ 800nm. The cured has relatively good heat resistance, the initial thermal decomposition temperature of the cured could be up to 315.8 °C. SEM observations show that the self-crosslinking silicone has a uniform, textured structure, higher transparency compared with the existing condensation silicone material, and can be used as advanced architectural translucent materials and optics packaging materials.


1991 ◽  
Vol 181 ◽  
pp. 71-77 ◽  
Author(s):  
J.K. Chen ◽  
T.B. Brill

RSC Advances ◽  
2014 ◽  
Vol 4 (74) ◽  
pp. 39463-39471 ◽  
Author(s):  
Rui Liu ◽  
Wenyuan Zhao ◽  
Tonglai Zhang ◽  
Li Yang ◽  
Zunning Zhou ◽  
...  

The styphnate of smaller size possesses lower decomposition temperature and higher reactivity.


2019 ◽  
Vol 2019 ◽  
pp. 1-8
Author(s):  
Yiping Shang ◽  
Wu Yang ◽  
Yabei Xu ◽  
Siru Pan ◽  
Huayu Wang ◽  
...  

In this study, few-layered tungsten disulfide (WS2) was prepared using a liquid phase exfoliation (LPE) method, and its thermal catalytic effects on an important kind of energetic salts, dihydroxylammonium-5,5′-bistetrazole-1,1′-diolate (TKX-50), were investigated. Few-layered WS2 nanosheets were obtained successfully from LPE process. And the effects of the catalytic activity of the bulk and few-layered WS2 on the thermal decomposition behavior of TKX-50 were studied by using synchronous thermal analysis (STA). Moreover, the thermal analysis data was analyzed furtherly by using the thermokinetic software AKTS. The results showed the WS2 materials had an intrinsic thermal catalysis performance for TKX-50 thermal decomposition. With the few-layered WS2 added, the initial decomposition temperature and activation energy (Ea) of TKX-50 had been decreased more efficiently. A possible thermal catalysis decomposition mechanism was proposed based on WS2. Two dimensional-layered semiconductor WS2 materials under thermal excitation can promote the primary decomposition of TKX-50 by enhancing the H-transfer progress.


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