Schematic representation viscometer

A schematic representation of a cone and plate viscometer is shown in Figure 3.1. In this case, the viscometer consists of a lower disc and an upper wide-angle cone. The sample fills the gap between the cone and the... 

FIG. 4.3 Schematic representation of a concentric-cylinder viscometer (a) geometry of a cup and bob and (b) volume element within a liquid gap. 

FIG. 4.4 Schematic representation of a cone-and-plate viscometer (the angle is greatly exaggerated). 

FIG. 7.11 Schematic representation of a surface viscometer (a) a monolayer is pushed through a narrow channel and (b) definition of variables for analysis. 

This type of measurements can very elegantly be realized online by coupling several detectors at the end of the SEC column such as a concentration detector (refractive index detector, spectrophotometric detector, etc.) and an absolute detector measuring the molar mass or related property of the separated species such as laser light scattering detector or capillary viscometer detector. These modern sophisticated separation systems allow not only the separation of the analyzed species but also their very detailed analysis and characterization as concerns the MMD or PSD, as well as other structural and compositional characteristics of simple polymers, co-polymers, etc. A schematic representation of a procedure of SEC data treatment from an experimental chromatogram to the final MMD or PSD data is shown in Figure 8. 

As a stand-alone method, the viscosity of a dilute polyethylene solution is normally measured using a capillary viscometer. A schematic representation of one such viscometer is shown in Figure 2. Detailed methodology for the use of such a capillary viscometer is found in ASTM D 1601. 

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