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Updated: Jul 30, 2026
07:28
Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Shear-induced transitions in a ternary polymeric system
Zvelindovsky1, Sevink, Fraaije
1Faculty of Mathematics and Natural Sciences, University of Groningen, Nijenborgh 4, 9747 AG Groningen, The Netherlands and Leiden Institute of Chemistry, Leiden University, Einsteinweg 55, 2300 RA Leiden, The Netherlands*.
Summary
This study presents the first 3D simulation of shear-induced phase transitions in polymers using dynamic density-functional theory. It explores pathways between bicontinuous and coexisting lamellar/cylinder phases under steady shear.
Area of Science:
- Polymer Science
- Materials Science
- Computational Chemistry
Background:
- Polymeric systems exhibit complex phase behaviors.
- Understanding shear-induced transitions is crucial for material processing.
- Previous simulations were limited in dimensionality.
Purpose of the Study:
- To perform the first three-dimensional simulation of shear-induced phase transitions in a polymeric system.
- To investigate the pathways between different mesophases under shear.
- To analyze the influence of simple steady shear on polymer blend morphology.
Main Methods:
- Dynamic density-functional theory (DDFT) was employed.
- Three-dimensional simulations were conducted.
- A mixture of flexible triblock ABA copolymer and solvent was studied.
Main Results:
- The simulation successfully modeled shear-induced phase transitions.
- Pathways between a bicontinuous phase with gyroid mesostructure and lamellar/cylinder phase coexistence were identified.
- The dynamics of morphological changes under steady shear were observed.
Conclusions:
- Three-dimensional simulations are feasible for studying shear-induced polymer phase transitions.
- DDFT provides a powerful tool for exploring complex polymer dynamics.
- The study elucidates the mechanisms driving phase transformations in block copolymers under flow.
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