Quality of SEC Analyses

Before discussing the parameters needed in the scaling of the number MWDs, some remarks regarding the quality of the SEC set-up should be made. Previous PLP studies of acrylates have reported a number of problems with broad and featureless MWDs, especially at higher temperatures [13, 16, 21, 32]. In this study, the MWDs obtained by PLP are fairly narrow, cf. for instance the MWDs as shown in figure 4.2 with typical MWD examples for acrylates as reported in several other studies [13, 16, 21, 25, 26], and up to 25°C the PLP peaks can clearly be distinguished from the background polymer. The experiments for EA 

It is important to note that the degree of chromatographic broadening in a SEC analysis can have an effect on the estimation of kp from experimental PLP SEC traces [34]. The comparison of kp values of EA determined by using one column set, with kp values of MA and BA that have been measured on a different column set-up could result in apparent differences between the A s of these monomers. Also this effect might contribute to the poor family-type behavior of these acrylates that was observed above. 

6 shows a typical example of a successful SEC analysis. It is clear from this figure that the quantitative determination of the MWD is by no means limited or influenced by baseline variations. 

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