6200 calorimeter

The heat of
explosion of the propellant and its combination with inhibitors was
assessed using a Parr 6200 calorimeter. The tester diagram is shown
in Figure S2 in Supporting Information.
Each inhibitor sample was placed at the bottom of the crucible and
weighed with 3 wt % of propellant grains. The tubular propellants
grains were sliced into sheets with a diameter of approximately 1
mm, and each crucible contained 5.5 g of the sheets. The loading mass
of each combination of propellant and inhibitor was 5.5 + 0.165 g.
Then, the crucible was placed in the bomb calorimeter, which would
be filled with 3.0 MPa nitrogen. Subsequently, the propellant samples
were initiated by a nichrome wire and raised to the temperature of
water in an adiabatic sleeve. Finally, according to the change in
temperature of water, the heat of explosion of propellant could be
calculated as follows where Q (J/g) and Q_f (J/g) are the heat of explosion of propellant
and heat released by the fuse, respectively; m_w (g) is the mass of water in each test; c_w (J/(g·°C)) is the heat capacity of water;
ΔT_W is the temperature rising value
of water; m_p (g) is the loading mass of
propellant grains; Furthermore, the initial temperature of deionized
water was 25 to 28 °C. The room temperature was 30 °C. For
each propellant composition, two samples were tested.

Calorimetric experiments were
performed using a Parr 6200 calorimeter. The fibrous pellets were
prepared using a Specac GS 15011 manual hydraulic press, and the samples
were then sealed in a steel crucible for examination. All experiments
were performed under an air atmosphere at 30 bar from 20 to 500 °C
at a heating rate of 10 °C/min.