Ver.1.36
5-4
STEP3 Loading sample
(1)
Place 5 µL
of the sample into an Eco cup SF and evaporate the solvent
(2)
Attach a stick (Eco stick SF) to the sample cup and fix it to the sampler. Push the slider of
the sampler down and attach the sampler to the pyrolyzer. Wait for 1 min (Fig. 5.5A).
STEP4 Click the
“START” button when temperatures and pressures are stabilized.
When the
“Ready for injection” dialog box is displayed, press the sample drop button located
at the top of the sampler. This drops the sample cup into the furnace (Fig. 5.5B). Immediately
click the
“Start” button. The GC analysis will start
The analysis result is shown in Fig. 5.6. From this EGA thermogram, the following can be observed.
(1)
Volatile components elute at temperatures between 50°C and 200°C.
(2)
The polymer decomposition starts about 350°C, and ends at 500°C.
Therefore, the EGA results indicate that the volatiles can be thermally desorbed between 50°C to
200°C, while the pyrolysis temperature for the polymer is 550°C.
Our experiences indicate that optimal
pyrolysis temperature should be set 50°C higher than the end of the EGA signal. This helps ensure
good reproducibility.
A) Attach the sampler with sample cup to
pyrolyzer
B) Press the sample drop button to drop
sample cup to furnace.
Fig. 5.5 Sample introduction procedure in EGA analysis
Fig. 5.6 EGA Thermogram
EGA analytical conditions
Furnace temp.: 50°C - 20°C/min - 600°C
ITF temp.: 300°C (Auto)
Injection port temp.: 300°C
Oven temp.: 300°C
EGA capillary tube: L=2.5 m, id.=0.15 mm
He: 1 mL/min, Split ratio: 1/50
Sample: Polystyrene solution 20
μl (100 μg)
MS scan range: 50-350 (m/z)
MS scan speed: 0.1 scan/second
Volatile compounds
Polymer
50
600 °C
200
300
400
500
