Rheology and Fourier transform rheology on water-based systems [Elektronische Ressource] / vorgelegt von Christopher Klein

Informations

• Publié par: johannes_gutenberg-universitat_mainz
• Publié le: 01 janvier 2005
• Nombre de lectures: 11
• Langue: English
• Poids de l'ouvrage: 10 Mo

Extrait

Rheology and Fourier-Transform Rheology on
water-based systems
Dissertation
zur Erlangung des Grades
Doktor der Naturwissenschaften
am Fachbereich Chemie
der Johannes Gutenberg-Universit¤at Mainz
vorgelegt von
Christopher Klein
geboren in Bad Kreuznach
Mainz April 2005Fur¤ Meine Eltern?Aus einem Buch abschreiben - Plagiat.
Aus zwei Buchern¤ - Essay.
Aus drei Buchern¤ abschreiben - Dissertation.
Aus vier Buchern¤ - ein funftes¤ gelehrtes Buch.?
Franz Molnar (1878-1952, ungar. Schriftsteller)Contents
Chapter 1 Introduction 1
Chapter 2 Theory 7
2.1 Basic principles in Rheology . . . . . . . . . . . . . . . . . . . 7
2.1.1 Phenomenological models based on spring and dashpot . . 9
2.1.2 The Peclet· number . . . . . . . . . . . . . . . . . . . . . . . 15
2.1.3 Pipkin diagram . . . . . . . . . . . . . . . . . . . . . . . . . 15
2.2 Electrostatic interactions in colloidal systems . . . . . . . . . . 18
2.2.1 Debye-length . . . . . . . . . . . . . . . . . . . . . . . . . . 18
2.2.2 The DLVO-theory . . . . . . . . . . . . . . . . . . . . . . . . 19
2.3 Theory and practical aspects of FT-rheology . . . . . . . . . . 22
2.3.1 Fourier Transformation . . . . . . . . . . . . . . . . . . . . . 22
2.3.2 Application of Fourier transformation on the stress signal . . 27
2.3.3 Methods to measure and quantify non-linearity . . . . . . . 30
In2.3.3.1 Magnitude to . . . . . . . 30
I1
2.3.3.2 The phase to quantify non-linearity . . . . . . . 31n
2.4 Dilute dispersions of nonspherical Particles . . . . . . . . . . . 35
2.4.1 Semi-dilute dispersions of Brownian rods . . . . . . . . . . 35
Chapter 3 Experimental Issues 41
3.1 set-up of the FT-rheology . . . . . . . . . . . . . 41
3.2 Couette Cell . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
3.3 Zero-shear viscosity . . . . . . . . . . . . . . . . . . . . . . 490
Chapter 4 Dispersions and Synthesis 53
4.1 Emulsion polymerisation . . . . . . . . . . . . . . . . . . . . . 55
4.1.1 Mechanism of the radical polymerisation . . . . . . . . . . . 58
iii CONTENTS
4.1.2 Semi-continuous emulsion polymerisation . . . . . . . . . . 61
4.1.3 Mini-emulsion polymerisation . . . . . . . . . . . . . . . . . 63
4.2 Characterisation methods for dispersions . . . . . . . . . . . . 65
4.2.1 Particle size . . . . . . . . . . . . . . . . . . . . . . . . . . . 65
4.2.2 Zeta-potential . . . . . . . . . . . . . . . . . . . . . . . . . . 67
4.2.3 Scanning Electron Microscopy . . . . . . . . . . . . . . . . . 69
4.2.4 Experimental issues of the synthesis . . . . . . . . . . . . . 69
Chapter 5 Materials 71
5.1 Dispersions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.2 FD-Virus . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
5.3 Polystyrene in DOP . . . . . . . . . . . . . . . . . . . . . . . . 73
Chapter 6 Improvement of a rheo-optical set-up 75
6.1 Theory of birefringence and dichroism . . . . . . . . . . . . . 75
6.2 Rheo-Optical set-up . . . . . . . . . . . . . . . . . . . . . . . . 77
6.2.1 Experimental set-up . . . . . . . . . . . . . . . . . . . . . . 77
6.2.2 Commercial set-up . . . . . . . . . . . . . . . . . . . . . . . 78
6.2.3 Modi ed set-up . . . . . . . . . . . . . . . . . . . . . . . . . 79
6.2.4 Homebuilt bob for the optical Couette cell . . . . . . . . . . 82
6.2.5 Background subtraction by hard and software measures,
ambiguity of the orientation angle and calibration . . . . . . 83
6.3 Background birefringence and experiments . . . . . . . . . . . 87
6.4 Conclusion of the chapter improvements in a rheo-optical set-up 97
Chapter 7 Mineralisation under shear 99
7.1 Materials . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
7.2 Experiments . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
7.3 Results and Discussion . . . . . . . . . . . . . . . . . . . . . . 103
Chapter 8 Rheological behaviour of highly lled dispersions under
steady shear and LAOS conditions 107
8.1 Linear rheology . . . . . . . . . . . . . . . . . . . . . . . . . . 108
8.2 Non-linear rheology . . . . . . . . . . . . . . . . . . . . . . . . 111CONTENTS iii
8.2.1 Non-linear behaviour under strain dependent LAOS condi-
tions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 112
8.2.2 Prediction and comparison of non-linearities under LAOS
conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116
8.3 Conclusion of the chapter rheological behaviour of highly
lled dispersions under steady and LAOS conditions . . . . . . 130
Chapter 9 Separation of LAOS-response into characteristic response
functions 133
9.1 Introduction of an analysis method for LAOS-response based
on characteristic response functions . . . . . . . . . . . . . . . 134
9.2 Conclusion of the chapter separation of LAOS-response into
characteristic response functions . . . . . . . . . . . . . . . . . 154
Chapter 10 Rheological behaviour of rod-like particles 157
10.1 Non-linear rheological properties of the FD-virus . . . . . . . 157
10.1.1 behaviour of FD-virus dispersions under strain
dependent LAOS conditions . . . . . . . . . . . . . . . . . . 157
10.1.2 Mechanical analysis of the FD-virus via FT-rheology . . . . . 159
10.1.3 Prediction of non-linear rheological properties according to
Dhont . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 164
10.1.4 Non-linear dissipative and elastic contribution of the viscosity168
10.2 Separation of LAOS-response into characteristic response
functions applied on a FD-virus dispersion . . . . . . . . . . . 173
10.3 Conclusion of chapter the rheological behaviour of rod-like
particles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 176
Chapter 11 Summary and Outlook 177
Appendix A Rheo-Optics 181
A.1 Background compensation for small angles . . . . . . . . . . . 181
A.2 General background compensation . . . . . . . . . . . . . . . 182
A.3 Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 183
Appendix B LabVIEW 185
B.1 VI Analyser with extended window function . . . . . . . . . . 185B.2 VI Reconstruct time signal . . . . . . . . . . . . . . . . . . . . 188
B.3 VI Birefringence-Dichroism . . . . . . . . . . . . . . . . . . . . 190
B.3.1 VI Main . . . . . . . . . . . . . . . 190
B.3.2 VI Initialisation . . . . . . . . . . . 192
B.3.3 VI Core . . . . . . . . . . . . . . . 192
Appendix C Chemicals 197
Appendix D Synthesis 199
D.1 of semi-continuous emulsion polymerisation . . . . 200
D.2 Synthesis of mini-emulsion polymerisation . . . . . . . . . . . 203
Bibliography 205
ivList of abbreviations
(NH ) S O APS ammonium peroxodiusulfate4 2 2 8
< D > intensity-weighted averaged diffusion coef cient
A area
AIBN azo-bis-isobutyrylnitrile
ARES Advanced Rheometer Expansion System
C stress optical coef cient
D diffusion coef cient
DLS dynamic light scattering
D rotational diffusion coef cientr
E electric eld strength
F force
FT Fourier Transformation
0
G (!) storage modulus
00
G (!) loss modulus
0 00
G (!) = G (!) + iG (!) complex modulus
HMT Hexamethylenetetramine
K S O KPS potassium peroxodiusulfate2 2 8
K cumulantn
v