obtained. For linear polyolefin samples, the extent of molar mass degradation as a
function of dissolution time is given in Fig. 4.14 for different methods and different
conditions. In the present case, 100 % stands for the initial molar mass before
degradation.
The molar masses obtained from HT-AF4 are significantly higher than the molar
masses obtained from HT-SEC at similar dissolution times, indicating significantly
higher degradation for the separations by HT-SEC. Quantification by HT-SEC only
Fig. 4.13 MMDs of linear UHM PE sample AK01 from HT-SEC and HT-AF4, dissolution time
and stabilization were varied, (a) HT-AF4, BHT and argon added; (b) HT-AF4, only argon added;
(c) HT-AF4, not stabilized; (d) HT-SEC, BHT and argon added; (e) HT-SEC, not stabilized
(reprinted from [31] with permission of Wiley-VCH)
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4 Field-Flow Fractionation