The sample is dissolved automatically and loaded into the TREF column to
undergo crystallization. The temperature rising elution is performed in isothermal
steps, as shown in Fig. 38, and at each temperature step the column is washed and
the solution injected into the GPC columns, in this particular example being an
LLDPE resin.
Cross-fractionation analysis performed with a sufficient number of isothermal
steps (high resolution) takes a longer time but provides unexpected views of the
Fig. 36 TREF-GPC [130]
Fig. 37 Cross-fractionation instrument TREF-GPC
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