Ferranti-Shirley cone and-plate viscometer

Figure 20. Shear stress developed in IGT polyisobutene pick test oil and a silicone oil as a function of shear rate in a Ferranti-Shirley cone and plate viscometer with a cone angle of 20 30" (22).

Viscosity measurements at constant temperature were made using a conventional Shirley—Ferranti cone-and-plate viscometer. In some cases complications arose due to phase inversion or to the fracture of low-molecular-weight polymer. One case was a typical one-shot flexible polyether foam system. On the other hand, a polyether prepolymer prepared from 2000 M.W. poly(oxypropylene)glycol and 80 20-TDI, reacted with water, formed a homogeneous system initially, and was suitable for study with this technique. The rate of viscosity increase at several temperatures is shown in Fig. 15. 

A cone and plate viscometer, such as the Ferranti-Shirley or the Weissenberg instruments, shears a fluid sample in the small angle (usually 4° or less) between a flat surface and a rotating cone whose apex just touches the surface. Figure 3f illustrates one such arrangement. This geometry has the advantage that the shear rate is everywhere uniform and equal io co/ sin, since the local cone velocity is cor and the separation between the... 

Prior to the removal of the film from the gel block, samples of liquid were rapidly removed at various temperature levels and their viscosities measured on a Ferranti-Shirley cone plate viscometer at 20°C. The amount of material required fcr each measurement was very small and enough could be obtained by making one pass with a small spoon spatula across the width of the plastisol. At a temperature... 

A Ferranti-Shirley cone-plate viscometer was interfaced to a minicomputer system by means of a microcomputer. The microcomputer collects data from the instrument corresponding to shear rate, shear stress and temperature. Data are transmitted to the minicomputer for storage, analysis and the generation of reports and plots. Four types of analyses are performed ... 

The Ferranti-Shirley Viscometer is a cone-plate type instrument which can be used in a variety of operating modes. Its durability and the wide temperature range accessible with this instrument have made it a valuable tool in the characterization of polymers and coatings. The main drawback in using this instrument for large numbers of samples has been that the time required to manually calculate, tabulate and plot the data obtained from the graphical output frequently exceeds the time required to make the experimental runs themselves. 

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