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Solution Blow Spinning of Polymeric Nano-Composite Fibers for Personal Protective Equipment

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Published on: March 18, 2021

Viscosity of polyelectrolyte-grafted nanoparticle solutions.

Koteswara Rao Medidhi¹, Venkat Padmanabhan

¹Department of Chemical Engineering, Tennessee Technological University, Cookeville, Tennessee 38501, USA. VPadmanabhan@tntech.edu.

|March 2, 2021

Summary

Charges and hydrogen bonding significantly impact polyelectrolyte-grafted nanoparticle solution viscosity. Electrostatic interactions and bridging networks formed by hydrogen bonds increase viscosity, influenced by chain stiffness and ionization.

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Area of Science:

Materials Science
Physical Chemistry
Polymer Science

Background:

Polyelectrolyte-grafted nanoparticles (PENP) are crucial in various applications.
Understanding factors influencing their solution viscosity is essential for material design.
Charges and hydrogen bonding are key intermolecular forces affecting solution properties.

Purpose of the Study:

To investigate the effects of charges and hydrogen bonding on the viscosity of PENP solutions.
To elucidate the mechanisms by which electrostatic interactions and hydrogen bonds influence PENP solution viscosity.
To explore the role of grafted chain length, ionization, and stiffness in viscosity modulation.

Main Methods:

Molecular dynamics (MD) simulations were employed to model PENP solutions.
Simulations analyzed electrostatic interactions between charged monomers on grafted chains.
Hydrogen bonding patterns and their influence on nanoparticle aggregation and solution viscosity were examined.

Main Results:

Increased ionization leads to polymer stretching and larger hydrodynamic size due to electrostatic repulsion.
Solution viscosity is governed by a balance between polymer entanglement and electrostatic repulsion.
Charge-assisted hydrogen bonds between particles significantly enhance viscosity, especially with bridging polymer chains.
Chain stiffness directly correlates with particle bridging and increased solution viscosity.

Conclusions:

Both electrostatic interactions and hydrogen bonding are critical determinants of PENP solution viscosity.
The formation of inter-particle hydrogen bonds and bridging networks effectively increases viscosity.
Grafted chain properties, including stiffness and ionization, play a significant role in tuning solution viscosity.