Title: From Molecular Constraints to Macroscopic Dynamics in Associative Networks Formed by Ionizable Polymers: A Neutron Spin Echo and Molecular Dynamics Simulations Study

Abstract

The association of ionizable polymers strongly affects their motion in solutions, where the constraints arising from clustering of the ionizable groups alter the macroscopic dynamics. The interrelation between the motion on multiple length and time scales is fundamental to a broad range of complex fluids including physical networks, gels, and polymer-nanoparticle complexes where long-lived associations control their structure and dynamics. Using neutron spin echo and fully atomistic, multimillion atom molecular dynamics (MD) simulations carried out to times comparable to that of chain segmental motion, the current study resolves the dynamics of networks formed by polystyrene sulfonate solutions for sulfonation fractions 0 ≤ f ≤ 0.09 across time and length scales. The experimental dynamic structure factors were measured and compared with computational ones, calculated from MD simulations, and analyzed in terms of a sum of two exponential functions, providing two distinctive time scales. These time constants capture confined motion of the network and fast dynamics of the highly solvated segments. A unique relationship between the polymer dynamics and the size and distribution of the ionic clusters was 2 established and correlated with the number of polymer chains that participate in each cluster. The correlation of dynamics in associative complex fluids acrossmore » time and length scales, enabled by combining the understanding attained from reciprocal space through neutron spin echo and real space, through large scale MD studies, addresses a fundamental long-standing challenge that underline the behavior of soft materials and affect their potential uses.« less

Authors:

Kosgallana, Chathurika ^[1]; Wijesinghe, Sidath  ^[2];

• Search DOE PAGES for author "Wijesinghe, Sidath"
• Search DOE PAGES for ORCID "0000-0002-4812-1034"

Senanayake, Manjula  ^[1];

• Search DOE PAGES for author "Senanayake, Manjula"
• Search DOE PAGES for ORCID "0000-0002-3139-0625"

Mohottalalage, Supun S. ^[1]; Ohl, Michael  ^[3];

• Search DOE PAGES for author "Ohl, Michael"
• Search DOE PAGES for ORCID "0000-0002-8656-8005"

Zolnierczuk, Piotr ^[3]; Grest, Gary S.  ^[4];

• Search DOE PAGES for author "Grest, Gary S."
• Search DOE PAGES for ORCID "0000-0002-5260-9788"

Perahia, Dvora  ^[5]

• Search DOE PAGES for author "Perahia, Dvora"
• Search DOE PAGES for ORCID "0000-0002-8486-8645"

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+ Show Author Affiliations

1. Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States
2. Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States, Department of ChemistryAppalachian State University, Boone, North Carolina 26808, United States
3. Neutron Scattering Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
4. Sandia National Laboratories, Albuquerque, New Mexico 87175, United States
5. Department of Chemistry, Clemson University, Clemson, South Carolina 29634, United States, Department of Physics, Clemson University, Clemson, South Carolina 29631, United States

Publication Date:

Thu Feb 22 00:00:00 EST 2024

Research Org.:

Clemson Univ., SC (United States); Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Los Alamos National Laboratory (LANL), Los Alamos, NM (United States)

Sponsoring Org.:

USDOE National Nuclear Security Administration (NNSA); USDOE Office of Science (SC), Basic Energy Sciences (BES). Materials Sciences & Engineering Division (MSE); National Science Foundation (NSF); USDOE Office of Science (SC), Basic Energy Sciences (BES). Scientific User Facilities (SUF)

OSTI Identifier:

2311006

Alternate Identifier(s):

OSTI ID: 2301683; OSTI ID: 2335869; OSTI ID: 2338245

Report Number(s):

SAND-2024-04642J
Journal ID: ISSN 2694-2453

Grant/Contract Number:  

AC02- 05CH11231.; NA-0003525; SC0019284; AC02-05CH11231; NA0003525; MRI-1725573

Resource Type:

Published Article

Journal Name:

ACS Polymers Au

Additional Journal Information:

Journal Name: ACS Polymers Au Journal Volume: 4 Journal Issue: 2; Journal ID: ISSN 2694-2453

Publisher:

American Chemical Society

Country of Publication:

United States

Language:

English

Subject:

36 MATERIALS SCIENCE; 97 MATHEMATICS AND COMPUTING; ionomer solutions; suflonated polystyrene; neutron spin echo; molecular dynamics simulations; exascale computing; dynamics; ionomer solutions, suflonated polystryene, neutron spin echo, molecular dynamics simulations, exascale computing, dynamics