Experiments using the simultaneous thermal analyzer

The experiments described in this section were performed using a Simultaneous Thermal Analyzer STA 780 (Stanton-Redcroft Ltd.). This instniment supplies the measuring signals temperature (T), weight (TGA), first derivative of weight with respect to time 

Each test carried out by the author was performed using an empty pan for reference. 

The evaporation peak results in a graph of the DTA peak maximum temperatures versus the carbon number which exhibits very little scattering (Fig. 3-36). The shape of the curve is similar to that of the boiling points (BP) from literature references (Fig. 3-15). A linear correlation exists  

The correlation is excellent with the eoefficient of correlation r = 0.99723. The graph of data of the peak areas versus the carbon number shows a higher degree of scattering (Fig. 3-37) which is likewise present in the graph of the data of the heats of vaporization (JT ) from literature referenees versus the carbon number (Fig. 3-38). Nevertheless the pattern of both curves shows the same direction. 

Comparison of the DTG and DTA temperatures of the peak maxima of the evaporation gives an average temperature differenee of 0.88 % of the measured value (maximum 1.66 %, minimum 0.27 %). The DTG maximum temperature seems to be somewhat lower than the DTA maximum but this difference is within experimental tolerance. So it may be assumed that the temperatures of the maximum of the evaporation rate and of the maximum of energy flow are identical. The conversions (weight losses) conesponding to those temperatures are also identical within experimental error. 

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