The effect of the simultaneous variation of sample mass and heating rate in DTA and DSC

Quantitative correlations between kinetic parameters (energy of activation, E), procedural factors (sample mass, m, and heating rate, φ) and the dependent variables (the temperature of inception of reaction, T_i, and temperature T_α at which a constant fraction α has decomposed) have been derived for differential thermal analysis (DTA) and differential scanning calorimetry (DSC). The relations have the same form as those derived from earlier TG studies. The dependent variables T_i and T_α are related to m, φ and E by the equations

where C₃ and C₂ are constants, and

where C₄ and C₅ are constants for a given α. The variation of C₅ with α is given by C₅ = a + b α where a and b are constants. The equations are applicable to TG, DTA and DSC.