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Handbook of Size Exclusion Chromatography and Related ...

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determination <strong>of</strong> the absolute molecular weights (if also necessary). For the<br />

calculation <strong>and</strong> presentation <strong>of</strong> the results PSS WinGPC 6.20 (Polymer St<strong>and</strong>ards<br />

Service, Mainz, Germany) was used.<br />

Successful fluoropolymer GPC analysis strongly depend on details <strong>of</strong> their<br />

structure <strong>and</strong> solubility. Over recent years we have investigated some<br />

fluoropolymers by GPC methods, but have not seen structures originating from<br />

alarge group <strong>of</strong> customers. Thus amethod covering alarge field <strong>of</strong> interests<br />

cannot be given.<br />

Pure <strong>and</strong> very expensive fluorinated eluents are used because <strong>of</strong> the high<br />

reproducibility <strong>of</strong> the results obtained in the following described applications.<br />

The high price <strong>of</strong> the eluent can be reduced when acompany specialized in<br />

high purity recycling (.99.8%) <strong>of</strong> expensive eluents is used as asupplier to the<br />

analytical laboratory. Contact details for such a source can be given by the<br />

author on request.<br />

4.1 Polyesters<br />

Most <strong>of</strong> the interest in investigating polyesters relates to polyethyleneterephthalates<br />

(PET), polybutyleneterephthalates (PBT), <strong>and</strong> the biodegradable polylactides.<br />

Figures 1to 5show typical results that are obtained on polyester analysis<br />

using PSS methods.<br />

Figure 1 Result <strong>of</strong> a PET analysis. Eluent: HFIP þ 0.05 M potassium-trifluoroacetate.<br />

Flow rate: 1 mL/min. Columns: PSS PFG 100 A ˚ ,7mm, 8 300 mm þ PFG 1000 A ˚ ,<br />

7 mm, 8 300 mm. Temperature: 258C. Detection: RI. St<strong>and</strong>ards: 12 PSS PMMA<br />

calibration st<strong>and</strong>ards.<br />

© 2004 by Marcel Dekker, Inc.

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