Retention Time Precision

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 and inlet and outlet tubing on the EcoSEC GPC System to deliver top GPC analysis performance.

Figure 1 demonstrates the superiority of the EcoSEC GPC System for the determination of weight-average molar masses.

Reproducibility of Mw analysis

Column:            TSKgel SuperMultiporeHZ-M, 4 µm, 4.6 mm ID × 15 cm × 2 Mobile phase:   THF Flow rate:          0.35 mL/min  Detection:          RI (EcoSEC GPC System) Temperature:     40 °C Injection vol.:    10 µL Samples:            poly(vinyl chloride-co-vinyl acetate) and polycaprolactone

Figure 2 shows a comparison of M_w reproducibility for a sample injected 10 times a day for 5 days on the EcoSEC GPC System compared to a conventional GPC. The reproducibility of the EcoSEC GPC System was superior by a factor of 3 to that of the conventional GPC system.

Comparing Mw reproducibility of the EcoSEC GPC System and a conventional GPC system

Column:           TSKgel SuperMultiporeHZ-M, 4 µm, 4.6 mm ID × 15 cm × 2 Mobile phase:  THF Flow rate:         0.35 mL/min  Detection:         RI Temperature:   40 °C Injection vol.:   10 µL Samples:           poly(vinyl chloride-co-vinyl acetate)