PE-LD, Lacqténe 1002TN22
Measuring Cell: TGA850 with sample changer and gas controller
Pan: Alumina 70 ul, no lid
Sample preparation: 7.246 mg cut from a pellet
TGA measurement: Heating from 40°C at 30 K/min with automatic gas switching from 650°C
Atmosphere: Nitrogen, 50 cm3/min; above 650°C air, 50 cm3/min
Both steps were evaluated with horizontal tangents
A series of measurements showed a standard deviation for the carbon black content of 0.014% when the 4 samples originated from one pellet, but 0.25% when several different pellets were used.
Polyethylene, the main component, pyrolizes between 400 and 600°C under nitrogen. The remaining carbon black burns after the switching and atmosphere to air. The remaining carbon black burns after switching the atmosphere to air. the higher the specific surface area or "activity" of the carbon black, the faster the combustion.
Note: A blank experiment was run prior to the PE measurement. The blank curve was automatically subtracted from subsequent measurements.
Compositional analysis by TGA is fast and accurate. In addition, qualitative information is obtained that characterizes the PE (TGA inflection point). Measuring samples from several different pellets allows the homogeneity of the product to be assessed.
PE, Compositional Analysis by TGA | Thermal Analysis Application No. HB 211 | Application published in METTLER TOLEDO TA Application Handbook Thermoplastics