Retention Time Precision
Molar mass averages can be affected by changes in the environment and measuring conditions. Generally, these variations are the result of one or more factors including flow rate reproducibility, baseline drift and injection reproducibility. In addition to controlling column temperature, Tosoh engineers added temperature control for both pumps, the degasser chamber and inlet and outlet tubing on the EcoSEC Elite GPC System to deliver top GPC analysis performance.
Figure 1 and Table 1 demonstrate the superiority of the EcoSEC Elite GPC System for the determination of weight-average molar masses.
Overlaid chromatogram of Vinyl chloride/vinyl acetate copolymer, intra day (n=10)
| Sample column: | TSKgel SuperMultiporeHZ-M x 2 |
| Reference column: | TSKgel SuperH-RC |
| Mobile phase: | THF |
| Flow rate: | 0.35 mL/min, Sample and Reference |
| Detection: | RI (EcoSEC Elite GPC System) |
| Temperature: | 40°C |
| Injection vol.: | 10 µL (1.0 g/L) |
| Intra day (n=10) | CV: 0.199% |
| Inter day (n=6) | CV: 0.376% |
| Vinyl chloride/vinyl acetate copolymer | ||
| Measurement date | Mw | CV(%) |
| Day 1 | 23165 | 0.305 |
| 2 | 23205 | 0.216 |
| 3 | 23029 | 0.109 |
| 4 | 23199 | 0.215 |
| 5 | 23091 | 0.182 |
| 6 | 23005 | 0.167 |
| AVG. | 2311 | 0.199 |
| RSD | 86.862 | - |
| CV(%) | 0.376 | - |
Figure 2 and Table 2 demonstrate the superiority of the EcoSEC Elite GPC System for elution time reproducibility
Overlaid chromatogram of std. Psts (F-2, F-10),
Intra day (n=10)
| Sample column: | TSKgel SuperMultiporeHZ-M x 2 |
| Reference column: | TSKgel SuperH-RC |
| Mobile phase: | THF |
| Flow rate: | 0.35 mL/min, Sample and Reference |
| Detection: | RI (EcoSEC Elite GPC System) |
| Temperature: | 40°C |
| Injection vol.: | 10 µL (0.2 g/L) |
| Intra day (n=10) | F2 CV: 0.016%; F10 CV: 0.013% |
| Inter day (n=6) | F2 CV: 0.022%; F10 CV: 0.018% |
| F-2 | F-10 | |||
| Measure ment date | Retention time (min) | CV(%) | Retention time (min) | CV(%) |
| Day 1 | 8.048 | 0.014 | 6.887 | 0.011 |
| 2 | 8.051 | 0.013 | 6.889 | 0.010 |
| 3 | 8.051 | 0.012 | 6.889 | 0.014 |
| 4 | 8.049 | 0.016 | 6.887 | 0.010 |
| 5 | 8.053 | 0.023 | 6.890 | 0.019 |
| 6 | 8.051 | 0.016 | 6.888 | 0.016 |
| AVG. | 8.050 | 0.016 | 6.888 | 0.013 |
| RSD | 0.002 | - | 0.001 | - |
| CV(%) | 0.022 | - | 0.018 | - |