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Size exclusion chromatograph column

Currently Available Size Exclusion Chromatographic Columns... [Pg.236]

On-line size exclusion chromatographic (SEC) analyses were performed with a Waters Model 401 differential refractometer (DR), a Waters Model 480 ultraviolet (UV) variable wavelength spectrophotometer and a Foxboro Miran lA infrared (IR) photometer, equipped with a zinc selenide ultramicro flowcell of 1.5 mm nominal pathlength and 4.5 /xl volume, purchased from the same supplier. A set of ten Mycrostyra-gel (Waters Associates) columns, regenerated by Analytical Sciences Inc. (ASI) and of nominal porosities 100, 500 (two) 10 (two), 10 (three), 10 and lO X, in the order given and a mobile phase flow rate of 1 ml/min was used. The column set had a specific resolution of 19.7 in 1,4-dioxane, as determined by the method of Yau(2). [Pg.170]

Columns used for size-exclusion chromatographic separations of macromolecules with different molecular masses are generally longer (25-100 cm) and broader (6-10 mm) than conventional analytical columns. Semi-preparative and preparative columns have internal diameters from 0.6 to 5 cm and even larger columns are used for industrial pilot-plant and process separations (see Chapter 6). [Pg.27]

Number-average molecular weights were determined in toluene solutions using a membrane osmometer (Mechrolab, Hewlett-Packard 503 with S S-08 membranes). Size exclusion chromatographic analyses in chloroform were performed by HPLC (Perkln-Elmer 601 HPLC) using two y-Styragel columns (lO", 10 A) after calibration with standard polystyrene samples. [Pg.38]

When a size-exclusion chromatograph is calibrated correctly, one can know the molecular weight of a polymer just based on the time it takes to pass, or elute through the column. From Fox and Flory s theory of solution viscosity one can learn that the size of a solvated macromolecular coil is directly correlated with its solution viscosity. The correlation is ... [Pg.105]

Figure 2.11 Schematic diagram of a gel permeation chromatograph (size exclusion chromatograph). The key elements are a pulseless pump, injection port, separation column containing appropriate crosslinked gel particles of controlled pore size, and one or more detector systems... Figure 2.11 Schematic diagram of a gel permeation chromatograph (size exclusion chromatograph). The key elements are a pulseless pump, injection port, separation column containing appropriate crosslinked gel particles of controlled pore size, and one or more detector systems...
An analytical TREF system was first described by Wild and Ryle [8], Their system (Fig. 8) used components taken from a Waters model 200 size exclusion chromatograph. The solvent reservoir, degasser and pump from the Waters unit was used as was the refractive index detector system. In place of the SEC oven a temperature programmed oil bath provided the temperature gradients. A 0.2 g polymer sample was loaded in a hot trichlorobenzene solution into a small column packed with 40-60 mesh Chromosorb P. Crystallization was achieved by slow-cooling the polymer solution (0.2 g in 5 ml) in the packed column at a rate of 1.5 K/hour down to room temperature. The temperature rising elution was carried out at a flow rate of 6 ml/min and a rate of temperature rise of 8 K/hour. The refractive index response and the separation temperature were recorded continuously on a two-pen recorder. A calibration curve of methyl content vs. elution... [Pg.13]

Upnmoor and Brunner [7] evaluated a packed column SFC with a light scattering detector using a mobile phase of carbon dioxide modified with methanol for the chromatography of polymer additives. Moulder and co-workers [8] transferred eluent fractions from a packed capillary size exclusion chromatographic (SEC) column using a solvent vented interface to an open tubular CSFC column. The system was evaluated for the analysis of polymer additives. [Pg.291]


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