Standard Test Method for Thermal-Oxidative Stability of Polypropylene Using a Specimen Rotator Within an Oven

Importancia y uso:

5.1 Under the severe conditions of this test method, the specimens undergo degradation at a rate that is dependent upon the thermal endurance of the polypropylene material under examination.

5.2 The thermal level of this test method is considered sufficiently severe to cause failure of commercial grades of heat-stable polypropylene within a reasonable period of time. If desired, lower temperatures can be applied to estimate the performance of polypropylene materials with lower heat stability.

5.3 The technique of specimen rotation described in this test method provides an estimate of the life-temperature relationship of polypropylene. If this test method is conducted at different temperatures on the same material, a more reliable estimate of the life-temperature relationship of polypropylene is determined. This test method can be conducted at several temperatures and the data interpreted through use of the Arrhenius relation, by plotting the logarithms of times to failure against the reciprocals of the temperatures in kelvins (K). Temperatures in the range from 100 to 150°C, with intervals of 10°C, are suggested for this purpose.

5.4 The stability as determined under the prescribed test method is not directly related to the suitability of the compound for a use where different conditions prevail.

5.5 The specimen rotation technique of thermal aging increases the probability that all specimens will be exposed similarly and that the effect of temperature gradients in an oven will be minimized.

Subcomité:

D20.15

Referida por:

D4000-23, D4101-24

Volúmen:

08.01

Número ICS:

83.080.20 (Thermoplastic materials)

Palabras clave:

aging; biaxial rotator; polypropylene; thermal aging; thermal oxidative stability;