Viscosity-Temperature Relationships

Some selected chemical and physical properties of naphthalene are given in Table 1. Selected values from the vapor pressure—temperature relationship for naphthalene are Hsted in Table 2, as are selected viscosity—temperature relationships for Hquid naphthalene. Naphthalene forms a2eotropes with several compounds some of these mixtures are Hsted in Table 3. 

Table 2. Selected Values of Vapor Pressure—Temperature and Viscosity—Temperature Relationship s for Naphthalene ...

The dependence of viscosity on temperature is critical to the handling of molten polymers in mol ding, extmsion, and other manufacturing processes. In fact, the drop in viscosity with increasing temperature makes these operations possible. Therefore, viscosity—temperature relationships are... 

The temperature dependence of melt viscosity at temperatures considerably above T approximates an exponential function of the Arrhenius type. However, near the glass transition the viscosity temperature relationship for many polymers is in better agreement with the WLF treatment (24). 

Asphalt Roofing Components. Asphalt (qv) is a unique building material which occurs both naturally and as a by-product of cmde-oil refining. Because the chemical composition of cmde oils differs from source to source, the physical properties of asphalts derived from various cmdes also differ. However, these properties can be tailored by further ptocessiag to fit the appHcation for which the asphalt will be used. Softening poiat, ductility, flash poiat, and viscosity—temperature relationship are only a few of the asphalt properties that ate important ia the fabricatioa of roofing products. 

Fig. 4. Kinematic viscosity—temperature relationship of dimethyl silicone fluids.

Fig. 1. Viscosity—temperature relationship of (a) FTypalon 40 (H) and SBR 1500 (S) and (b) various Hypalon polymers A, Hypalon 4085 B, Hypalon 48 C,...

The slag viscosity-temperature relationship for completely melted slag is... 

Solvent extraction removes harmful constituents such as heavy aromatic compounds from lubricating oils to improve the viscosity-temperature relationship. The usual solvents for extracting lubricating oil are phenol and furfural. 

Materials. Samples of dewatered crude oils were obtained from the Athabasca oil sands of the McMurray formation by extraction using the commercial hot water process (Suncor Inc.) the Bl uesky-Bu11 head formation at Peace River, Alberta by solvent extraction of produced fluids the Clearwater formation at Cold Lake, Alberta by solvent extraction of core material and the Karamay formation in Xing-Jiang, China. A summary of the physical and chemical properties of the crude oils, including chemical composition, and density-temperature and viscosity-temperature relationships, is given in Table I. 

Most viscosity-temperature relationships for glasses take the form of an Arrhenius expression, as was the case for binary metal alloys. The Vogel-Fulcher-Tammann (VFT) equation is one such relationship. 

From the viscosity-temperature relationship of various Kuwait crudes, it was noticed tnat in different areas the treating temperatures shall have to be different depending on the crude oil mixture. However, the best test is ir. the fields and the optimum temperatures for treating can be arrived at with experience. 

Fig. 3. Viscosity-temperature relationship of a typical commercial soda-lime glass...

The viscosity-temperature relationship of mineral oil fractions, and in fact of many other liquids, can be represented by a formula proposed by Cornelissen and Waterman24... 

Fig. 48. Schematical representation of the viscosity-temperature relationship of liquids with a certain con stant average value of x the slope A of the line is equai...

Fox TG, Flory PJ (1948) Viscosity-molecular weight and viscosity-temperature relationships for polystyrene and polyisobutylene. J Am Chem Soc 70(7) 2384-2395 Freed KF, Edwards SF (1974) Polymer viscosity in concentrated solutions. J Chem Phys 61(9) 3626-3633... 

M24--------Viscosity-temperature relationships for dilute solutions of cellulose... 

The viscosity-temperature relationship and its dependence on previous shear history... 

Viscosity is an important characteristic of pitches used as binders for the production of carbon and graphite electrodes. We used a Haake balance to measure SCT, petroleum and coal tar pitch viscosity, SCT pitches have viscosity between 1000-4000 cps at 160°C, A comparison of the viscosity-temperature relationship of two SCT pitches prepared by thermal and catalytic processes, a commercial petroleum and a coal tar pitch used for the production of carbon anodes is given in Figure 2. 

Three points are noteworthy for the Kyukoshi method. (i) Rapid heating of the hydrogenated pitch to above 450°C produces a pitch suitable for smooth spinning. (ii) This pitch appears to be isotropic at the spinning temperature of 370°C. (iii) The viscosity-temperature relationship, plotted in Figure 8 in terms of the Andrade equation... 

New viscosity-temperature relationship, 539 NLO phenomena, 351 NMR spectroscopy, 375 Nomenclature of solution viscosity, 250 Nominal strain, 386 stress, 736... 

VanKrevelen-Hoftijzer viscosity-temperature relationship, 539 Van t Hoff equation, 751 Velocities of sound waves, 390 Velocity gradient, 526 Vertical Burning Test, 854 Vicat softening temperature, 849 Vickers hardness test, 837 Viscoelasticity, 405... 

Sopade, P.-A., Halley, P., Bhandari, B., D Arcy, B., Doebler, C., and Caffin, N. 2003. Application of the Williams-Landel-Ferry model to the viscosity-temperature relationship of Australian honeys. J. Food Eng. 56(1) 67-75. 

Figure 4.12 The points give the measured viscosity-temperature relationship for e-terphenyl, while the shaded regions are the viscosities predicted by the Adam-Gibbs equation (4-10) using A5(7 ) measured for o-terphenyl. The two shaded regions represent alternative fits of the Adam-Gibbs parameters, one fit to the high-temperature, and the other to the low-temperature, data. (From Greet and Turnbull, reprinted with permission, from J. Chem. Phys. 47 2185, Copyright 1967, American Institute of Physics.)...

Figure 1 shows that the viscosity-temperature relationship revealed by plotting In 77 against VT is linear for the base (1) and compositions 1 (2) and 2 (3) with additive content up to 20 wt% for other analyzed fluids (4), (5), and (6) this relationship is not linear. Therefore, we may conclude that the flow of some analyzed fluids does not obey the activation mechanism described by the Arrhenius-Frenkel-Eiring equation within the studied temperature range. 

Fig. 1. Viscosity-temperature relationship in Arrhenius coordinates. Curve numbers correspond to liquid numbers of Table 3.

Figure 2 demonstrates that the viscosity-temperature relationship revealed by plotting Xarj against I T-Tq) is linear for all compositions studied as well as for oligoethylsiloxane and additive. The calculations show that all the analyzed fluid flows within the analyzed temperature range with maximum relative error 2%, obeying the Falcher-Tamman equation (fiee volume concept) [3] ... 

The foregoing data concerning the applicability of the Falcher-Tamman equation to the description of the viscosity-temperature relationship of the compositions and the nonapplicability of the Arrhenius-Ftenkel-Eiring equation testify to the fact that the viscous flow of the compositions influences not only energetic but also structural factors that are considered by flee volume theory. 

Thus, the conducted research showed that absolute reaction rate theory is not applicable to the explanation of the composition s viscosity-temperature relationship. It was found that the fi e volume theory allows us to describe the viscosity-temperature relationship with satisfactory accuracy within the studied temperature range from nunus -20 to 50 C. Parts of the fi ee fluctuation volume and viscous flow activation energy values determining fluids properties were calculated. 

---