Acta Phys. -Chim. Sin. ›› 2013, Vol. 29 ›› Issue (10): 2087-2094.doi: 10.3866/PKU.WHXB201308301

• THERMALANALYSIS KINETICS ANDTHERMOKINETICS • Previous Articles     Next Articles

Effects of Lead Complex-Based BTATz on Thermal Behaviors, Non-Isothermal Reaction Kinetics and Combustion Properties of DB/RDX-CMDB Propellants

LI Wen1, REN Ying-Hui1,2, ZHAO Feng-Qi2, ZHANG Xian-Bo1, MA Hai-Xia1, XU Kang-Zhen1, WANG Bo-Zhou2, YI Jian-Hua2, SONG Ji-Rong1,3, HU Rong-Zu2   

  1. 1 Shaanxi Key Laboratory of Physico-inorganic Chemistry, School of Chemical Engineering, Northwest University, Xi'an 710069, P. R. China;
    2 Science and Technology on Combustion and Explosion Laboratory, Xi'an Modern Chemistry Research Institute, Xi'an 710065, P. R. China;
    3 Conservation Technology Department, The Palace Museum, Beijing 100009, P. R. China
  • Received:2013-06-14 Revised:2013-08-30 Published:2013-09-26
  • Contact: REN Ying-Hui E-mail:nwuryh@163.com
  • Supported by:

    The project was supported by the National Natural Science Foundation of China (21101127, 21073141), National Defense Pre-Research Foundation of China (9140A28020111BQ3401), and National Defense Pre-Research Foundation of China (A3120110005).

Abstract:

The composite double base (DB)/hexogen (RDX)-modified double base (CMDB) propellants (Nos. DB001 and CMDB100) were prepared with the lead complex of 3,6-bis(1H-1,2,3,4-tetrazol-5-ylamino)-1,2,4,5-tetrazine (LCBTATz), with and without the ballistic modifier. Their thermal behaviors and nonisothermal decomposition reaction kinetics were investigated by thermogravimetry, derivative thermogravimetry (TG-DTG), and differential scanning calorimetry (DSC). For the LCBTATz-DB propellant, there was one mass loss stage in the TG curve and one exothermic peak in the DSC curve over the temperature range 350-540 K. For LCBTATz-CMDB, there were two continuous exothermic stages in the TG curve, and only one corresponding exothermic peak in the DSC curve over the range 390-540 K. The exothermal decomposition reaction mechanisms of LCBTATz-DB and LCBTATz-CMDB follow the functions f(α)=α-1/2 and f(α)=2(1-α)3/2, respectively (α: conversion degree). The self-accelerating decomposition temperatures (TSADT), thermal ignition temperatures (TTITT), critical temperatures of thermal explosion (Tb), adiabatic timesto-explosion (tTlad), and thermodynamic parameters of activation reaction were calculated, and the thermal safety was evaluated. For DB001, TSADT=444.50 K, TTITT=453.96 K, Tb=471.84 K; tTlad=39.36 s. For CMDB100, TSADT=442.38 K, TTITT=452.89 K,Tb=464.13 K,tTlad=21.3 s. As a high-efficiency combustion catalyst, LCBTATz in double-base propellants increases the propulsion rate and reduces the pressure index for larger scale pressures. This makes the DB propellant appear to have a significant super burning effect at 2-8 MPa and a "mesa effect" at 8-12 MPa. Meanwhile, the pressure exponent of the CMDB propellant decreased to 0.18.

Key words: 3,6-Bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine, Lead salt, Double-bas propellant, Composite modified double base propellant, Nonisothermal kinetics, Thermal safety, Combustion property

MSC2000: 

  • O643