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Linking models of polymerization and dynamics to predict branched polymer structure and flow
Daniel J Read1, Dietmar Auhl, Chinmay Das
1Department of Applied Mathematics, University of Leeds, Leeds LS2 9JT, UK.
Science (New York, N.Y.)
|October 1, 2011
Summary
This study introduces a predictive scheme linking polymer branching structure to viscoelasticity. The method accurately predicts polymer melt properties, enabling in silico material design.
Area of Science:
- Polymer Science
- Materials Science
- Rheology
Background:
- Predicting the viscoelastic properties of complex polymer melts is challenging.
- Industrial polymers often exhibit stochastic branching, complicating structure-property relationships.
Purpose of the Study:
- To develop a predictive scheme connecting polymer topology to viscoelasticity.
- To calculate linear and nonlinear viscoelasticity from polymerization kinetics.
- To enable in silico design of new polymer materials.
Main Methods:
- Combining numerical simulation of polymerization with tube/entanglement polymer dynamics.
- Extending polymer dynamics to fully nonlinear response.
- Analyzing stochastically branched polymer melts, such as high-pressure free radical polyethylene.
Main Results:
- The scheme successfully predicts viscoelasticity based on polymer formation kinetics.
- Calculations for low-density polyethylenes show good agreement with experimental data.
- The method reveals molecular origins of optimized melt rheology.
Conclusions:
- The predictive scheme offers a powerful tool for understanding polymer melt behavior.
- It bridges fundamental polymer science with industrial processing and material design.
- This approach facilitates the in silico design of advanced polymer materials with tailored rheology.
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