Capillary rheology

Capillary rheology tests, 19 578 Capillary separations, 4 602-647 sample preparation, 4 609-610 Capillary viscometers, 21 726-731 commercial, 21 729 uses of, 21 727... 

Figure 3.27 Cone and plate and capillary rheology data for a specialty PE resin. A slight shift in the rheology occurs between the two methods at a shear rate of 100 1 /s...

Strahm, B., Plainer, B., Huber, G., and Rokey, G. (2000). Application of food polymer seienee and capillary rheology in evaluating complex extmded products. Cereal Foods World, 45(7), 300-302. 

Capillary rheometry and parallel-plate rheometry use the fact that wall slip will manifest itself as a geometry-dependent phenomenon. That is, wall slip will appear as a geometric effect on apparent rheological properties. In the capillary-rheometer technique, slip will manifest itself as an effect of capillary diameter ( )) on the shear stress (t, ). Wall slip in capillary rheology can be calculated from an analysis that involves the following ... 

Similar to Table 17.9 (capillary rheology), Table 17.10 (dynamic rheology) shows that a change of the shear rate by 100 times led to a decrease in the shear viscosity in 25 times for HDPE and approximately in 60, 70, and 160 times for three different regrinds. 

Fig. 2. Capillary rheological curves of base materials, (Extr. temper. = 200 C).

Watts D C, Combe E C, Greener E H (1980) Capillary rheology of two composite resin systems. J Oral Rehab, 1, 475 80. 

S. Hui, T.K. Chaki, S. Chattopadhyay, Dynamic and capillary rheology of LDPE-EVA-based thermoplastic elastomer effect of silica nanoflller, Polymer Composites 31 (3) (2010) 377-391. 

Figure 14.4 Capillary rheology of 30% glass fiber-reinforced SPS versus 30% glass fiber-reinforced liquid crystalline polymer (LCP),poly(l,4cyclohexamethylene tere-phthalate) (PCI), and polybutylene terephthalate (PBT). All resins were tested 50°C above their melting point.

There is a relationship [18] between torque (Nm), M, and rotor speed (rpm),, which can be described by the familiar power law, and can be used for calculation of the power index, n. Figure 5 shows variation of equilibrium torque (torque at point S as in Figure 4) vs. rpm at 335"C. A power index obtained from Figure 5 is n=0.58, which is consistent with Saini [12] and capillary rheological results presented above. 

The viscosity of CPE is typically influenced by a combination of die molecular weight of the starting polyethylene and the level of chlorine added to the polyethylene. The combination of these factors contributes to the viscosity of the CPE, as measured by such tests as Mooney viscosity or capillary rheology. In general, the viscosity of CPE is controlled by the combination of the polyethylene feedstock molecular weight and the amount of chlorine added to the polyethylene backbone. However, other factors can affect the viscosity such as the MWD of the polyethylene, additives in the final CPE product, and the presence of residual crystaUinity. 

Figure 5A. Capillary rheology curves - Lexan DMX2415 compared to Lexan 121R and 141...

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