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Universal scaling for polymer chain scission in turbulence
Siva A Vanapalli1, Steven L Ceccio, Michael J Solomon
1Department of Chemical Engineering, Macromolecular Science and Engineering Program, University of Michigan, Ann Arbor, MI 48103, USA.
Summary
Turbulence, not laminar flow, causes polymer chain scission in experiments. This finding, based on over 40 years of data, reveals stress at the Kolmogorov scale drives bond breakage, simplifying polymer dynamics and enabling control.
Area of Science:
- Fluid Dynamics and Polymer Physics
- Nonlinear Dynamics and Complex Systems
Background:
- Previous polymer chain scission experiments in strong flows were analyzed using laminar flow theories.
- Existing experimental data showed anomalies when compared to accepted laminar flow scission theories.
- These anomalies suggested an unaccounted-for factor in polymer scission dynamics.
Purpose of the Study:
- To reconcile discrepancies between existing polymer scission theories and experimental results.
- To investigate the role of turbulence in polymer chain scission experiments.
- To develop a new theoretical framework for understanding polymer scission in turbulent flows.
Main Methods:
- Reassessment of over 40 years of experimental data on polymer chain scission.
- Hypothesis formulation: local stress at the Kolmogorov scale causes molecular tension.
- Theoretical analysis connecting Kolmogorov scale stress to polymer covalent bond breakage.
Main Results:
- Demonstrated that turbulence significantly affected previous polymer chain scission experiments.
- Proposed a universal scaling law for polymer scission in turbulent flows based on the new hypothesis.
- Showed that molecular tension leading to bond breakage originates from stress at the Kolmogorov scale.
Conclusions:
- The study simplifies the theoretical understanding of polymer dynamics leading to scission.
- The findings allow for the controlled scission of polymers in commercial applications and genomic DNA.
- Turbulence is a critical factor in polymer chain scission, necessitating revised theoretical models.
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