PLgel MIXED

A linear calibration curve achieved using PLgel mixed gel columns infers several key advantages in SEC analyses. 

TABLE 12.2 Operating Ranges for PLgel Mixed Gel Columns... 

The use of mixed gel technology has become widespread since the late 1980s. If the column is well designed it should not he necessary to supplement resolution in certain areas of the operating range (particularly the extremes) hy the addition of individual pore size columns. This practice is not necessary or recommended for PLgel mixed gel columns, although it is a common practice for other commercial products. 

FIGURE 19.3 Comparison of pSty standards on Polymer Laboratories PLgel mixed A 20-/Ltm and Waters HT IO- Am columns. 

Columns 2 x Plgel mixed bed-E (Polymer Laboratories), 30 cm, 3 pm packing... 

SEC calibration curves for PLgel MIXED gels, column dimensions 300 x 7.5 mm, eluant tetrahydrofuran, flow rate 1 ml/minute, calibrants narrow polydispersity polystyrene, detector UV 254 nm. 

Chromatograms of polybistrifluoroethoxyphosphazene using different detectors (a) differential refractometer, (b) differential viscometer, and (c) intrinsic viscosity. Column PLgel mixed bed. Mobile phase acetone, cyclohexanone. Temperature 30°C, 40°C. [From T. H. Mourey et al. (1989)... 

Effect of ionic strength on the elution profile of a modified com starch with DMSO as the mobile phase at 80°C. The columns are Plgel Mixed (29). (Reprinted with permission from the publisher, John Wiley Sons.)... 

SEC conditions instmment. Waters ALC/GPC -150C column, two PLgel mixed mobile phase, DMSO with 0.03 M NaNOj temperature, 80°C for injector and column compartments injection ... 

Figure 23-10 Purification of carbon nanotubes by molecular exclusion chromatography. An electric arc struck between graphite rods creates nanometer-size carbon products, including tubes with extraordinary strength and possible use in electronic devices. Molecular exclusion chromatography separates nanotubes (fraction i) from other forms of carbon in fractions 2 and 3. The stationary phase is PLgel MIXED-A, a polystyrene-divinylbenzene resin with pore sizes corresponding to a molecular mass range of 2 000 to 40 000 000 Da. Images of carbon in each fraction were made by atomic force microscopy. [B. Zao, H. Hu, S. Niyogi, M. E. Itkis. M. A. Hamon, P. Bhowmik, M. S. Meier, and R. C. Haddon, . Am. Chem. Soc. 2001, i23,11673.]...

NP 4- to 85-mole ethoxylates, single broad SEC peak determination of molecular weight distribution Polymer Laboratories PLgel mixed-C 10 -10 A, 7.5 X 300 mm and Waters Ultrastyragel 100 A, 7.8 x 300 mm, 4(FC THE RI 272... 

The solutions were filtered prior to injection with 0.45 pm lluoropolymer membrane filters. A set of two 30 cm size exclusion columns (PLgel mixed B, 10 pm particle size. Polymer Laboratories) was used. The mobile phase was DMSO with O.IM LiBr. 

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