ASTM D4419 Standard Test Method for Measurement of Transition Temperatures of Petroleum Waxes by Differential Scanning Calorimetry (DSC)
13. Report
13.1 Report the corrected apex and end temperatures for each of the transition peaks to the nearest 0.5°C in order of occurrence. First thermal transition apex (T1A), first thermal transition end temperature (T1E), second thermal transiton apex temperature (T2A), and second thermal transition end temperature (T2E), transition temperature of petroleum waxes by DSC.
14. Precision and Bias
14.1 Precision - The precision of this test method as obtained by statistical examination of interlaboratory test results is as follows:
14.1.1 Repeatability - The difference between successive test results, obtained by the same operator with the same apparatus under constant operating conditions on identical test material, would, in the long run, in the normal and correct operation of the test method, exceed the following values only in one case in twenty:
14.1.2 Reproducibility - The difference between two single and independent results, obtained by different operators working in different laboratories on identical test material, would, in the long run, in the normal and correct operation of the test method, exceed the following values only in one case in twenty:
NOTE 9 - DSC will not differentiate between solid-liquid and solid-solid transitions; other techniques must be used for example, melting point in accordance with Test Method D87.
14.1.3 The first thermal transition temperature precision data are based on duplication determinations on five different petroleum waxes in an interlaboratory study among six laboratories. The second thermal transition temperature precision data are based on duplicate determinations on two different petroleum waxes in an interlaboratory study among six laboratories.
14.2 Bias - The procedure in this test method has no bias because the value of transition temperatures can be defined only in terms of a test method.
15. Keywords
15.1 differential scanning calorimetry; petroleum wax; thermal properties; transition temperature