Naslov
Applicability of Thermal Methods in Stability Studies of Homogeneous Propellants

Autori
Sućeska, Muhamed ; Matečić Mušanić, Sanja ; Rajić Linarić, Maša

Vrsta, podvrsta i kategorija rada
Radovi u zbornicima skupova, cjeloviti rad (in extenso), znanstveni

Izvornik
Theory and Practice of Energetic Materials / Wang, Yajun ; Huang, Ping ; Li, Shengcai - Lahti : Science Pres, 2005, 118 - 131

Skup
2005. International Autumn Seminar on Propellants, Explosives and Pyrotechnics (2005 IASPEP)

Mjesto i datum
Peking, Kina, 24.10.2005. - 28.10.2005

Vrsta sudjelovanja
Predavanje

Vrsta recenzije
Međunarodna recenzija

Ključne riječi
homogeneous propellants; stability; thermal methods; differential scanning calorimetry; thermogravimetry

Sažetak
The ageing of homogeneous propellants, which is consequence of chemical decomposition reactions and physical processes, limits their safe and reliable service life. Under certain condition the decomposition may become autocatalytic and can lead to the well-known phenomena of self-ignition. Therefore it is of great importance to determine accurately a propellant stability at a given moment of storage time, as well as to predict self-ignition probability under given conditions. The ageing of the propellants causes the change of a number of relevant propellants properties (e.g. decrease of nitrocellulose molar mass, decrease of stabiliser content, decrease of specimen mass, change of mechanical properties, change of ballistic properties, change of thermal properties, etc.). Thus, the quality of a propellant at a given moment of time, i.e. its stability, may be determined by measuring these properties. In this work we have studied thermal properties of stable nitrocellulose and double base propellants, as well as properties of the same type of propellants artificially and naturally aged, in order detect and to quantify changes in thermal properties that can be used in the propellants stability assessment. Thermal properties were studied using differential scanning calorimetry (DSC) and thermogravimetry (TGA), and both isothermal and non-isothermal measurements. It was found out that the ageing causes changes of DSC and TGA curves’ shape. The changes are quantified by values of some characteristic points/parameters on DSC curves (e.g. DSC peak onset temperature, peak maximum temperature, peak height and width, heat of reaction, maximum heat flow rate etc.) and TGA curves (e.g. mass loss at a certain time of isothermal measurements, time necessary to reach certain degree of conversion under isothermal measurements etc.). Also, it was found that the most sensitive parameters to the ageing process, i.e. points on DSC and TGA curves, are: peak height and width, heat of reaction, maximum heat flow rate, mass loss at a given time, and rate of mass loss at a given time. These parameters may help one in propellants stability evaluation.

Izvorni jezik
Engleski

Znanstvena područja
Kemija, Kemijsko inženjerstvo

POVEZANOST RADA