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MORE SOLUTIONS TO STICKY PROBLEMS: TABLE OF CONTENTS
INTRODUCTION ..................................................... 1
CHAPTER 1 ...........................................................
1.1 Why Make Rheological Measurements? ....
1.2 Thinking Rheo-Logically .............................
1.3 Three Schools of Thought on Viscosity
Measurement .............................................
1.3.1 The Pragmatic School .......................
1.3.2 The Theoretical School .....................
1.3.3 The Academic School .......................
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CHAPTER 2 ............................................................ 3
2.1 Equipment for Specific Situations ............... 3
2.2 Viscometers ................................................ 3
2.3 Rheometers ................................................ 3
2.4 Spindle Geometries .................................... 4
2.4.1 Disc Spindles .................................... 4
2.4.2 Cylindrical Spindles ........................... 4
2.4.3 Coaxial Cylinders .............................. 4
2.4.4 Cone/Plate Geometry ........................ 4
2.4.5 T-Bar Spindles ................................... 4
2.4.6 Vane Spindles ................................... 5
2.5 Temperature Control ................................... 5
2.5.1 Temperature Baths ............................ 5
2.5.2 Thermosel System ............................ 5
2.5.3 Peltier (Thermo-electric Systems) ..... 5
2.6 Small Sample Volume ................................ 5
2.6.1 Small Sample Adapter ....................... 5
2.6.2 UL Adapter ........................................ 5
2.6.3 DIN Adapter ....................................... 5
2.6.4 Thermosel System ............................ 5
2.6.5 Cone/Plate Systems .......................... 5
2.7 Low Viscosity .............................................. 5
2.7.1 UL Adapter ........................................ 6
2.7.2 Small Sample Adapter ....................... 6
2.7.3 Thermosel System ............................ 6
2.7.4 Wells-Brookfield Cone/Plate Viscometer ............................................................. 6
2.8 High Temperature ....................................... 6
2.8.1 Thermosel System ............................ 6
2.8.2 Temperature Baths ............................ 6
2.8.3 Cone/Plate with
Embedded Heating .................................... 6
2.9 Defined Shear Rate .................................... 6
2.10 High Shear Rate ....................................... 7
2.10.1 Wells-Brookfield Cone/Plate Viscometer/Rheometer .......................................... 7
2.10.2 CAP Viscometer/Rheometer ........... 7
2.10.3 R/S Rheometer ............................... 7
2.10.4 PVS Rheometer .............................. 7
MORE SOLUTIONS TO STICKY PROBLEMS
2.11 Defined Shear Stress ................................
2.12 Non-Flowing Sample Materials .................
2.12.1 Helipath Stand .................................
2.12.2 Spiral Adapter ..................................
2.12.3 Vane Spindles .................................
2.13 Special Accessory Items ...........................
2.13.1 Quick Connect .................................
2.13.2 Spindle Extensions ..........................
2.14 Fumes and Hazardous Locations .............
2.14.1 Purge Fittings ..................................
2.14.2 Explosion-Proof Construction ..........
2.15 Process Control ........................................
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CHAPTER 3 ............................................................ 9
3.1 Why You Should Read This Chapter .......... 9
3.2 How the Brookfield Viscometer Works ....... 9
3.3 Spring Torque ........................................... 10
3.4 Viscosity Measurement Techniques ......... 10
3.4.1 Record Keeping .............................. 10
3.4.2 The Spindle and the Guardleg ........ 10
3.4.3 Selecting a Spindle Speed .............. 10
3.4.4 Sample Container Size .................... 11
3.4.5 Sample Conditions ........................... 11
3.4.6 Spindle Immersion ........................... 11
3.4.7 Sensitivity and Accuracy .................. 11
3.4.8 Obtaining a Viscometer Reading ..... 11
3.4.9 A Calibration Check ......................... 12
3.4.10 Recalibrating the Brookfield
Viscometer ............................................... 12
3.5 Viscometer Maintenance .......................... 13
3.6 Viscometer Troubleshooting ..................... 14
CHAPTER 4 .......................................................... 14
4.1 Coming to Grips with Rheology ................ 14
4.2 Viscosity .................................................... 14
4.3 Newtonian Fluids ...................................... 15
4.4 Non-Newtonian Fluids .............................. 15
4.5 Thixotropy and Rheopexy ......................... 16
4.6 Laminar and Turbulent Flow ..................... 17
4.7 Yield Behavior ........................................... 17
4.8 What Affects the Rheological Property? ... 18
4.8.1 Temperature .................................... 18
4.8.2 Shear Rate ...................................... 18
4.8.3 Measuring Conditions ..................... 19
4.8.4 Time ................................................ 19
4.8.5 Pressure .......................................... 19
4.8.6 Previous History .............................. 20
4.8.7 Composition and Additives .............. 20
4.8.8 Special Characteristics of Dispersions
and Emulsions .......................................... 20
Page 56
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