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Updated: Jul 3, 2026
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Orientational Transition in a Liquid Crystal Triggered by the Thermodynamic Growth of Interfacial Wetting Sheets
Published on: May 15, 2017
Phase transition with nonthermodynamic states in reversible polymerization.
1Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545, USA.
Summary
This study reveals a nonequilibrium phase transition in reversible polymerization. A critical fragmentation threshold dictates whether polymer systems reach a thermodynamic steady state or exhibit nonthermodynamic behavior with unique length distributions.
Area of Science:
- Statistical Mechanics
- Polymer Physics
- Chemical Kinetics
Background:
- Investigating polymerization dynamics, focusing on reversible aggregation and fragmentation.
- Exploring systems where individual polymer dynamics are reversible but macroscopic behavior may not be.
- Understanding phase transitions in non-equilibrium systems.
Purpose of the Study:
- To analyze a reversible polymerization model with molecular weight-dependent aggregation and fragmentation rates.
- To identify and characterize a nonequilibrium phase transition in this system.
- To determine the influence of fragmentation strength on steady-state properties and polymer length distributions.
Main Methods:
- Theoretical investigation of a reversible polymerization process.
- Analysis of polymer aggregation and fragmentation dynamics.
- Characterization of system-size dependence and polymer length distributions under varying fragmentation rates.
Main Results:
- A nonequilibrium phase transition was observed despite reversible dynamics.
- Above a critical fragmentation threshold, a thermodynamic steady state emerges with polymer number proportional to system size and exponential length distribution tails.
- Below the threshold, a nonthermodynamic steady state occurs with sublinear polymer number growth and algebraic length distribution tails, where the exponent depends on fragmentation rate.
Conclusions:
- Reversible polymerization can exhibit nonequilibrium phase transitions.
- The fragmentation rate critically determines the system's steady-state nature and polymer length distribution characteristics.
- This model provides insights into complex behaviors arising from simple, reversible microscopic dynamics.
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