Hyphenated SEC techniques

Both SEC-FUR and SEC-MS are mainly used to provide information on the chemical composition of 

Both a pneumatic heated nozzle system [487] and an ultrasonic nozzle/vacuum system [699] have been described for removing the troublesome solvent in order to simplify IR analysis. The former system (LC Transform ) has been commercialised [700], and allows full use of the mid-IR spectral range by providing analyte films free from solvent interference. The evaporative 

Cheung et al. [702] have evaluated various solvent evaporative high-temperature SEC-FTIR interfaces. This detection approach was initially employed only for qualitative analysis, but is recently also being used quantitatively. For that purpose the polymer film quality generated by the interface is of critical importance (thickness effects). Table 7.76 lists the main features of evaporative SEC-FITR for polymer analysis. 

The technique offers advantages over alternative techniques (e.g. preparative SEC fractionation followed by IR). SEC-FTIR is much more suitable to quantitation of additives than SEC-MALDI-ToFMS. Combining SEC-FTIR with SEC-MALDI offers a more powerful tool than when either is used alone. 

Applications Applications of SEC-FTIR include quantitative analysis of copolymers [701] product deformulation of hot melt adhesives characterisation of polymer compositional heterogeneity analysis of complex mixtures of urethane oligomers and eventually also the identification and quantitative analysis of polymer additives 

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