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09:06
Evaluation of the Curing of Adhesive Systems by Rheological and Thermal Testing
Published on: July 3, 2020
Confinement and viscoelastic effects on chain closure dynamics.
Pinaki Bhattacharyya1, Rati Sharma, Binny J Cherayil
1Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India.
The Journal of Chemical Physics
|July 12, 2012
Summary
Cellular confinement and viscoelasticity impact polymer cyclization. We found that chain closure time scales with chain length and confinement size or noise correlation, affecting reaction rates in biological systems.
Area of Science:
- Biochemistry
- Polymer Physics
- Cellular Biophysics
Background:
- Cellular reactions are influenced by confinement and viscoelasticity.
- Polymer cyclization is a key reaction in cellular biochemistry.
Purpose of the Study:
- To investigate how confinement and viscoelasticity affect polymer cyclization.
- To determine the scaling relationship between polymer chain length and cyclization time under different conditions.
Main Methods:
- Utilized the Rouse model of polymer dynamics.
- Applied the Wilemski-Fixman approximation.
- Analyzed polymer dynamics under confinement and colored Gaussian noise.
Main Results:
- Found that mean closure time scales with chain length (N) and confinement radius (d) as t(c) ~ Nd(2) when confined.
- Determined that under colored Gaussian noise, t(c) ~ N(2/(2-2H)), where H characterizes noise correlations.
- Observed a scaling of t(c) ~ N(3.4) at H=0.7, indicating slow chain relaxation in viscoelastic media.
Conclusions:
- Confinement and viscoelasticity significantly alter polymer cyclization dynamics.
- The scaling relationships provide insights into reaction kinetics within cellular environments.
- Results highlight the importance of considering cellular microenvironment effects on biochemical reactions.
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