Low shear viscosity and crystallization in dilute solutions of polymers at high pressures: Falling body viscometry of high molecular weight polyethylene solutions

1995 ◽  
Vol 35 (22) ◽  
pp. 1781-1784 ◽  
Author(s):  
Rashi Akki ◽  
Scott Bair ◽  
A. S. Abhiraman
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Shear Viscosity ◽  
High Pressures ◽  
Dilute Solutions ◽  
Low Shear Viscosity ◽  
Low Shear

scholarly journals A re-examination of the interaction of vinculin with actin.

1986 ◽  
Vol 102 (3) ◽  
pp. 1085-1092 ◽  
Author(s):  
J A Wilkins ◽  
S Lin
Keyword(s):  
Molecular Weight ◽  
Sodium Dodecyl Sulfate ◽  
Shear Viscosity ◽  
Sodium Dodecyl ◽  
Gel Filtration ◽  
Apparent Molecular Weight ◽  
Active Protein ◽  
High Affinity ◽  
Low Shear Viscosity ◽  
Low Shear

Vinculin prepared by published procedures (i.e., Feramisco, J. R., and K. Burridge, 1980, J. Biol. Chem., 255:1194-1199) contains contaminants that have been shown by Evans et al. (Evans, R. R., R. M. Robson, and M. H. Stromer, 1984, J. Biol. Chem., 259:3916-3924) to reduce the low-shear viscosity of F-actin solutions. In this study we separated contaminants from conventional vinculin preparations by hydroxylapatite chromatography. We found that although the contaminants represented a small fraction (less than or equal to 5%) of the total protein in the conventional vinculin preparations, they were responsible for practically all of the filament capping and bundling activities previously attributed to vinculin. In addition, we examined the size of the molecule(s) responsible for the observed capping activity and found that its apparent molecular weight under denaturing conditions in sodium dodecyl sulfate (SDS) polyacrylamide gels fell within a broad range of 23,000-33,000. These results contrast with the observation that under nondenaturing conditions, the activity migrated in gel filtration columns at a position that corresponded to the Stoke's radius of a much bigger molecule. Since the migration of the activity in these chromatographic experiments is independent of the presence of vinculin, it is unlikely that the active protein associates with vinculin with high affinity under the conditions examined.

Low shear viscosity of polypropylene melts

1963 ◽  
Vol 1 (7) ◽  
pp. 381-384 ◽  
Author(s):  
D. Poller ◽  
A. M. Kotliar ◽  
R. L. Kruse
Keyword(s):  
Shear Viscosity ◽  
Low Shear Viscosity ◽  
Low Shear

The Equation of State and the Temperature, Pressure, and Shear Dependence of Viscosity for a Highly Viscous Reference Liquid, Dipentaerythritol Hexaisononanoate

2016 ◽  
Vol 139 (1) ◽  
Author(s):  
Scott Bair ◽  
Tsuyoshi Yamaguchi
Keyword(s):  
Molecular Weight ◽  
Shear Stress ◽  
Equation Of State ◽  
High Molecular Weight ◽  
Free Volume ◽  
Newtonian Limit ◽  
Scaling Models ◽  
The Difference ◽  
Better Than ◽  
Low Shear

Measurements are reported for dipentaerythritol hexaisononanoate (DiPEiC9) of pressure–volume–temperature (pVT) response to pressures to 400 MPa and temperatures to 100 °C, and of viscosity at pressures to 700 MPa and temperatures to 90 °C and shear stress to 18 MPa. These data complement the low-shear viscosities published by Harris to pressures to 200 MPa and the compressions by Fandiño et al. to 70 MPa. The improved Yasutomi correlation reproduces all viscosity measurements with accuracy better than the Doolittle free volume and the Bair and Casalini thermodynamic scaling models which require an equation of state (EoS). The interaction parameter for thermodynamic scaling, γ = 3.6, is less than that reported by Harris (γ = 4.2) and the difference is primarily in the choice of EoS. The shear stress at the Newtonian limit, about 6 MPa, is exceptionally large given the high molecular weight of DiPEiC9. The large Newtonian limit is also seen in the oscillatory shear response.

Dispersion and Rheological Properties of Alumina Freeze Casting Slurries Containing Nanoparticle/Whisker SiC

2007 ◽  
Vol 280-283 ◽  
pp. 1035-1038 ◽  
Author(s):  
Tae Young Yang ◽  
Young Min Park ◽  
Gun Dae Lee ◽  
Seog Young Yoon ◽  
Ron Stevens ◽  
...  
Keyword(s):  
Shear Rate ◽  
Shear Viscosity ◽  
Pure Alumina ◽  
Rheological Measurements ◽  
Continuous Shear ◽  
Suspension Viscosity ◽  
Low Shear Viscosity ◽  
Opposite Manner ◽  
High Structure ◽  
Low Shear

The sedimentation density significantly decreased after addition of dispersant; the effect was more pronounced with pure alumina, as compared with SiC-containing slurry. With further addition of surfactant, the sedimentation density increased somewhat, but decreased with binderadditions. The suspension viscosity generally behaved in an opposite manner to the sedimentation density, i.e., low sedimentation density gave high low-shear viscosity, indicative of high structure formation in the suspended particles. Shear rate rheological measurements showed continuous shear thinning behavior.

The Measurement of Viscosity of Liquids Under Tension

2003 ◽  
Vol 125 (2) ◽  
pp. 260-266 ◽  
Author(s):  
Peter A. Kottke ◽  
Scott S. Bair ◽  
Ward O. Winer
Keyword(s):  
Shear Viscosity ◽  
Initial Pressure ◽  
Viscosity Coefficient ◽  
Absolute Zero ◽  
Viscosity Data ◽  
Hydrostatic Tension ◽  
Low Shear Viscosity ◽  
Low Shear

The rheological significance of a state of hydrostatic tension was investigated. A method for measuring the limiting low shear viscosity of liquids under tension was developed. The ability of nine liquids to withstand tension was verified, and the magnitudes of tension achievable through different methods were compared. The use of viscosity data from liquids under tension to more accurately determine the initial pressure viscosity coefficient was investigated. The continuity of the pressure viscosity coefficient across absolute zero pressure was verified.

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