Rheology for Polymer Melt Processing

✍ Scribed by Piau J.-M., Agassant J.-F.

• Year: 1996
• Tongue: English
• Leaves: 435
• Category: Library

✦ Synopsis

This book presents the main results obtained by different laboratories involved in the research group ''Rheology for polymer melt processing'' which is associated with French universities, schools of engineering, and the CNRS (Centre National de la Recherche Scientifique - France). The group comprises some 15 research laboratories of varied disciplines (chemistry, physics, material sciences, mechanics, mathematics), but with a common challenge viz. to enhance the understanding of the relationships between macromolecular species, their rheology and their processing. Some crucial issues of polymer science have been addressed: correlation of viscoelastic macroscopic bulk property measurements and models, slip at the wall, extrusion defects, correlation between numerical flow simulations and experiments.Features of the book:- The book is unique in that it allows one to grasp the key issues in polymer rheology and processing at once through a series of detailed state-of-the-art contributions, which were previously scattered throughout the literature.- Each paper was reviewed by experts and the book editors and some coordination was established in order to achieve a readable and easy access style.- Papers have been grouped in sections covering successively: Molecular dynamics, Constitutive equations and numerical modelling, Simple and complex flows.- Each paper can be read independently.Since the book is intended as an introduction to the main topics in polymer processing, it will be of interest to graduate students as well as to scientists in academic and industrial laboratories.

✦ Table of Contents

Front Cover......Page 1
Rheology for Polymer Melt Processing......Page 4
Coppyright Page......Page 5
Contents......Page 8
Preface......Page 6
Introduction......Page 12
The reptation model......Page 13
Diffusion measurements in polymer systems......Page 17
Interpretation and comparison with rheometrical data......Page 22
Conclusions......Page 26
Introduction......Page 28
Temporary network structures......Page 31
Segmental motions : dynamic screening effect......Page 39
Molten high polymers : semi-local dynamics......Page 44
Conclusion......Page 46
Introduction......Page 48
Theoretical background in Infrared dichroism......Page 49
Experimental......Page 50
Theoretical basis of interpretation......Page 52
Results and discussion on isotopically labeled chains......Page 55
Results and discussion on isotopically labelled 6-arm stars......Page 60
Results and discussion on binary blends of long and short chains......Page 66
Conclusion......Page 72
Introduction......Page 76
Methodology......Page 77
Elongational flow......Page 84
Shear flow......Page 98
Conclusions and perspectives......Page 104
Introduction......Page 106
Linear viscoelastic behaviour of linear and flexible chains - basics and phenomenology......Page 107
The case of entangled monodisperse linear species : pure reptation......Page 116
Entangled model-branched polymers......Page 125
Entangled polydisperse linear chains : double reptation......Page 130
Effects of non entangled chains......Page 140
Problems still pending......Page 146
Introduction......Page 152
Theoretical aspects......Page 155
Experimental aspects......Page 170
Experimental validation of the Wagner model......Page 178
Experimental validation of the Phan Thien-Tanner model......Page 187
Conclusion......Page 186
Introduction. The models......Page 210
Maxwell type models : loss of evolution and change of type......Page 212
Steady flows......Page 214
Unsteady flows......Page 219
Stability issues......Page 225
Numerical analysis of viscoelastic flows......Page 236
Conclusion......Page 241
Introduction......Page 248
Computation of a purely viscous flow......Page 251
Finite elements method for viscoelastic flows......Page 255
Conclusion......Page 263
General relationships and usefulness of birefringence measurements......Page 268
Validity of the stress optical law......Page 275
Application to complex flow studies......Page 288
Conclusion......Page 292
Introduction......Page 296
Constitutive equations......Page 300
Flow geometries and experiments......Page 306
Numerical models......Page 311
Comparison between numerical results and experiments......Page 328
Conclusions......Page 344
Introduction......Page 348
Local determination of the velocity at the wall......Page 349
Molecular models and discussion......Page 359
Conclusions......Page 364
Introduction......Page 368
Means used......Page 370
Flow in high surface energy dies......Page 372
Flow in dies with low surface energy......Page 383
Discussion and conclusion......Page 395
Introduction......Page 400
Experimental facilities and flow curves......Page 402
Visualization of upstream flow......Page 408
Observation of stable flow - sharkskin......Page 413
Observation of unstable flow for slightly to moderately entangled polymers - melt fracture......Page 419
Highly entangled polymers - flow with slip......Page 424
Conclusion......Page 426
SUBJECT INDEX......Page 432