Polyacrylate chromatogram

Chromatograms can be made handleable and storable by treatment with plastic dispersions, based on polyacrylic ester, polyvinyl chloride or polyvinyl propionate, such as, for example, Neatan (Merck) [21 — 23]. In order to avoid clogging the spray head with plastic dispersion residue it is recommended that it be rinsed through immediately after use with tetrahydrofuran or that disposable jets be employed [24]. 

Fig. 4.28. Total ion current GC-MS chromatogram for BTX and phenol mixtures in water. (A) Extracted with a polydimethylsiloxane coating. (B) Extracted with a polyacrylate coating. K is the coating/water partition coefficient of the analyte, which drops by more than 2 orders of magnitude for o-xylene and increases by more than 1 for 2,4-dichlorophenol upon changing the coating from non-polar polydimethylsiloxane to polyacrylate. (Reproduced with permission of the American Chemical Society.)...

FIG. 9 Change in molecular weight distribution of polyacrylic acid in solution with time during adsorption onto BaTi03 (no electrolyte added). C0 chromatogram before adsorption chromatograms after adsorption for the indicated time in hours (h) or days (d). (Adapted from Ref. 28.)... 

Amino acid chromatograms have been preserved by impregnation with collodion to which a definite amount of glycerol had been added [42, 66]. Chromatograms have also been pasted over with self-adhesive plastic film and the layer subsequently peeled off the plate [354]. Spraying with polymer dispersions (polyacrylates, polyvinylidene chloride or polyvinyl propionate) is usually more suitable [402]. Such aerosols are commercially available (Firms 88, 153). Mention may be made also of impregnation of layers by immersion in solutions of polymers although this has a restricted application (Firm 60). 

Penalver et al. [178] have applied SPME coupled to HPLC with ECD and UV detection to determine the 11 phenolic compoimds considered priority pollutants by the US EPA. In this work, 85 mm polyacrylate fibers were used to extract the analytes from the aqueous samples. They have compared static and d)mamic desorption modes. They found out that the static desorption showed better recoveries for the phenolic compounds. The authors evaluated the performance of the SPME-HPLC-UV-ECD with river water and waste-water samples. The method enabled the determination of phenolic compounds at low levels in these water samples. Figure 16.5 shows [178] the chromatograms for the Ebro river water sample spiked with 1 mg/L for ECD, and 0.1 mg/L for UV detection. 

Figure 13. Chromatogram of mixed higher alkyl alcohols obtained during thermal degradation of a higher polyacrylate (time in minutes)...

Figure 6 Overlaid capillary gas chromatograms showing the response differences of ethanol and n-propanol toward 100-(im polydimethylsiloxane and 85-(un polyacrylate SPME phases. The solution (1.0 mL) was analyzed by headspace SPME in a 4-inL Teflon-sealed vial. An extraction time of 5 minutes at 40°C was used for the experiment.

---