scholarly journals Burning Characteristics of Ammonium-Nitrate-Based Composite Propellants with a Hydroxyl-Terminated Polybutadiene/Polytetrahydrofuran Blend Binder

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Makoto Kohga ◽  
Tomoki Naya ◽  
Kayoko Okamoto

Ammonium-nitrate-(AN-) based composite propellants prepared with a hydroxyl-terminated polybutadiene (HTPB)/polytetrahydrofuran (PTHF) blend binder have unique thermal decomposition characteristics. In this study, the burning characteristics of AN/HTPB/PTHF propellants are investigated. The specific impulse and adiabatic flame temperature of an AN-based propellant theoretically increases with an increase in the proportion of PTHF in the HTPB/PTHF blend. With an AN/HTPB propellant, a solid residue is left on the burning surface of the propellant, and the shape of this residue is similar to that of the propellant. On the other hand, an AN/HTPB/PTHF propellant does not leave a solid residue. The burning rates of the AN/HTPB/PTHF propellant are not markedly different from those of the AN/HTPB propellant because some of the liquefied HTPB/PTHF binder cover the burning surface and impede decomposition and combustion. The burning rates of an AN/HTPB/PTHF propellant with a burning catalyst are higher than those of an AN/HTPB propellant supplemented with a catalyst. The beneficial effect of the blend binder on the burning characteristics is clarified upon the addition of a catalyst. The catalyst suppresses the negative influence of the liquefied binder that covers the burning surface. Thus, HTPB/PTHF blend binders are useful in improving the performance of AN-based propellants.

2011 ◽  
Vol 399-401 ◽  
pp. 279-283
Author(s):  
Wei Qiang Pang ◽  
Hui Xiang Xu ◽  
Yang Li ◽  
Xiao Bing Shi

The theoretical performances of NEPE (nitrate ester plasticized polyether) propellant with and without ADN were calculated with minimum free energy method. The burning characteristics and the thermal decomposition of propellants were determined by nickel chromium wire method and TG- DTG, respectively. The SEM of NEPE propellants and the mechanical sensitivity were also detected. The results show that the specific impulse and the adiabatic flame temperature are increase with an increase in the content of ADN oxidizer. The burning rate and pressure exponent of propellant with a change of pat content of ADN can be boosted higher than those of the AP formulations.


2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Yi Yang ◽  
Xinjie Yu ◽  
Jun Wang ◽  
Yaxue Wang

Kneading time is adjusted to change the dispersibility of nano-CuO in AP/HTPB (Ammonia Perchlorate/Hydroxyl-Terminated Polybutadiene) composite propellants. Nano-CuO/AP is prepared to serve as the other dispersing method of nano-CuO, named predispersing procedure. Several kinds of heat releasing, thermal decomposition by DSC, combustion heat in oxygen environment, and explosion heat in nitrogen environment, are characterized to learn the effect of dispersibility of nano-CuO catalyst on heat releasing of propellants. With pre-dispersing procedures, thermal decomposition temperature of nano-CuO/AP and its propellant are about C and C lower than that of AP simple mixed with nano-CuO and its propellant, respectively. Comparing propellant with simple mixed nano-CuO kneading 3 hours, combustion heat and explosion heat of propellant with nano-CuO/AP increase about 1.4% and 1.7%, respectively. However, because of the breaking of nano-CuO/AP structure during kneading procedure, combustion heat and explosion heat of all the samples are decreased with the increase of kneading time after 3 hours.


2014 ◽  
Vol 924 ◽  
pp. 200-211 ◽  
Author(s):  
Er Gang Yao ◽  
Feng Qi Zhao ◽  
Si Yu Xu ◽  
Rong Zu Hu ◽  
Hui Xiang Xu ◽  
...  

Aluminum nanopowders coated with oleic acid (nmAl+OA), perfluorotetradecanoic acid (nmAl+PA) and nickel acetylacetonate (nmAl+NA) were prepared. The combustion characteristics of hydroxyl terminated polybutadiene (HTPB) composite solid propellants containing different coated aluminum nanpowders were investigated. The result shows that the burning rate of the propellant sample containing nmAl+NA is the highest at different pressure, the maximum burning rate is up to 26.13 mm·s-1at 15 MPa. The burning rates of propellant samples containing nmAl+OA and nmAl+PA are almost the same at different pressures, and higher than the propellant samples containing untreated aluminum nanopowders only at the pressure range of 10 ~ 15 MPa. The flame brightness of different propellants under different pressure is not the same. The flame brightness is increased with the pressure increasing. The flame center zone brightness of the propellant containing nmAl+PA and nmAl+NA is brighter under 4 MPa, and the brightness of nmAl+NA is the brightest. The surface coating of aluminum nanopowder has little effect on the combustion flame temperature of solid propellant. The burning surface temperature increases with the pressure increasing.


1992 ◽  
Vol 57 (11) ◽  
pp. 2302-2308
Author(s):  
Karel Mocek ◽  
Erich Lippert ◽  
Emerich Erdös

The kinetics of the reaction of solid sodium carbonate with sulfur dioxide depends on the microstructure of the solid, which in turn is affected by the way and conditions of its preparation. The active form, analogous to that obtained by thermal decomposition of NaHCO3, emerges from the dehydration of Na2CO3 . 10 H2O in a vacuum or its weathering in air at room temperature. The two active forms are porous and have approximately the same specific surface area. Partial hydration of the active Na2CO3 in air at room temperature followed by thermal dehydration does not bring about a significant decrease in reactivity. On the other hand, if the preparation of anhydrous Na2CO3 involves, partly or completely, the liquid phase, the reactivity of the product is substantially lower.


2013 ◽  
Vol 31 (1) ◽  
pp. 1-26 ◽  
Author(s):  
Shalini Chaturvedi ◽  
Pragnesh N. Dave

1972 ◽  
Vol 25 (10) ◽  
pp. 2107 ◽  
Author(s):  
GB Deacon ◽  
GD Fallon

Bismuth triarenesulphinates, Bi(02SR)3 [R = Ph, p-MeC6H4, p-ClC6H4, 2,4,6-(Me2CH)3C6H2, and p-MeCONHC6H4], have been prepared by reaction of bismuth triacetate with the appropriate arenesulphinio acids in glacial acetic acid, and the first two compounds have also been obtained by reaction of triphenyl-bismuth with the appropriate mercuric arenesulphinates. The sulphur-oxygen stretching frequencies of the bismuth sulphinates are indicative of O-sulphinate coordination, and the compounds are considered to be polymeric with bridging O-sulphinate groups and six-coordinate bismuth. Thermal decomposition of Bi(O2SR)3 (R = Ph, p-MeC6H4, or p-CIC6H4) under vacuum gave the corresponding triarylbismuth compounds and sulphur dioxide, the preparation of tri-p-chlorophenylbismuth being accompanied by formation of di-p-chlorophenyl sulphone and S-p-chlorophenyl p-chlorobenzenethiosulphonate. Pyrolysis of the other triarenesulphinates did not yield organobismuth compounds.


2014 ◽  
Vol 1082 ◽  
pp. 387-390
Author(s):  
Hui Sheng Zhou ◽  
Xing Hua Xie ◽  
Kang Xu

The main background was the "3.11" accident in this paper. The starting point was based on the experts’ conclusions of investigation and analysis in the accident. Combining the decomposition mechanism of ammonium nitrate in the emulsion explosives and the lessons from the production of emulsion explosives explosion, the conditions of the emulsion explosives (matrix) thermal decomposition in the emulsifier are given that are the formation of hot spot and the accumulation of heat. Then the factors of hot spots generated in the production of emulsion explosives and the occurred conditions of the heat accumulation are analyzed and summarized.


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