Link between Morphology, Structure, and Interactions of Composite Microgels
Rivas-Barbosa, Rodrigo ; Ruiz-Franco, José ; Lara-Peña, Mayra A. ; Cardellini, Jacopo ; Licea-Claverie, Angel ; Camerin, Fabrizio LU
; Zaccarelli, Emanuela
and Laurati, Marco
(2022)
In Macromolecules
55(5).
p.1834-1843
- Abstract
We combine small-angle scattering experiments and simulations to investigate the internal structure and interactions of composite poly(N-isopropylacrylamide)-poly(ethylene glycol) (PNIPAM-PEG) microgels. At low temperatures the experimentally determined form factors and the simulated density profiles indicate a loose internal particle structure with an extended corona that can be modeled as a starlike object. With increasing temperature across the volumetric phase transition, the form factor develops an inflection that, using simulations, is interpreted as arising from a conformation in which PEG chains are incorporated in the interior of the PNIPAM network. This gives rise to a peculiar density profile characterized by two dense,... (More)
We combine small-angle scattering experiments and simulations to investigate the internal structure and interactions of composite poly(N-isopropylacrylamide)-poly(ethylene glycol) (PNIPAM-PEG) microgels. At low temperatures the experimentally determined form factors and the simulated density profiles indicate a loose internal particle structure with an extended corona that can be modeled as a starlike object. With increasing temperature across the volumetric phase transition, the form factor develops an inflection that, using simulations, is interpreted as arising from a conformation in which PEG chains are incorporated in the interior of the PNIPAM network. This gives rise to a peculiar density profile characterized by two dense, separated regions, at odds with configurations in which the PEG chains reside on the surface of the PNIPAM core. The conformation of the PEG chains also have profound effects on the interparticle interactions: Although chains on the surface reduce the solvophobic attraction typically experienced by PNIPAM particles at high temperatures, PEG chains inside the PNIPAM network shift the onset of attractive interaction at even lower temperatures. Our results show that by tuning the morphology of the composite microgels, we can qualitatively change both their structure and their mutual interactions, opening the way to explore new collective behaviors of these objects.
(Less)
- author
- Rivas-Barbosa, Rodrigo
; Ruiz-Franco, José
; Lara-Peña, Mayra A.
; Cardellini, Jacopo
; Licea-Claverie, Angel
; Camerin, Fabrizio
LU
; Zaccarelli, Emanuela
and Laurati, Marco
- publishing date
- 2022-03-08
- type
- Contribution to journal
- publication status
- published
- in
- Macromolecules
- volume
- 55
- issue
- 5
- pages
- 10 pages
- publisher
- The American Chemical Society (ACS)
- external identifiers
-
- scopus:85125128163
- ISSN
- 0024-9297
- DOI
- 10.1021/acs.macromol.1c02171
- language
- English
- LU publication?
- no
- additional info
- Publisher Copyright: © 2022 American Chemical Society. All rights reserved.
- id
- 7736f563-473b-4db7-8241-9b1256342456
- date added to LUP
- 2024-02-22 14:08:45
- date last changed
- 2024-02-24 03:25:43
@article{7736f563-473b-4db7-8241-9b1256342456,
abstract = {{<p>We combine small-angle scattering experiments and simulations to investigate the internal structure and interactions of composite poly(N-isopropylacrylamide)-poly(ethylene glycol) (PNIPAM-PEG) microgels. At low temperatures the experimentally determined form factors and the simulated density profiles indicate a loose internal particle structure with an extended corona that can be modeled as a starlike object. With increasing temperature across the volumetric phase transition, the form factor develops an inflection that, using simulations, is interpreted as arising from a conformation in which PEG chains are incorporated in the interior of the PNIPAM network. This gives rise to a peculiar density profile characterized by two dense, separated regions, at odds with configurations in which the PEG chains reside on the surface of the PNIPAM core. The conformation of the PEG chains also have profound effects on the interparticle interactions: Although chains on the surface reduce the solvophobic attraction typically experienced by PNIPAM particles at high temperatures, PEG chains inside the PNIPAM network shift the onset of attractive interaction at even lower temperatures. Our results show that by tuning the morphology of the composite microgels, we can qualitatively change both their structure and their mutual interactions, opening the way to explore new collective behaviors of these objects.</p>}},
author = {{Rivas-Barbosa, Rodrigo and Ruiz-Franco, José and Lara-Peña, Mayra A. and Cardellini, Jacopo and Licea-Claverie, Angel and Camerin, Fabrizio and Zaccarelli, Emanuela and Laurati, Marco}},
issn = {{0024-9297}},
language = {{eng}},
month = {{03}},
number = {{5}},
pages = {{1834--1843}},
publisher = {{The American Chemical Society (ACS)}},
series = {{Macromolecules}},
title = {{Link between Morphology, Structure, and Interactions of Composite Microgels}},
url = {{http://dx.doi.org/10.1021/acs.macromol.1c02171}},
doi = {{10.1021/acs.macromol.1c02171}},
volume = {{55}},
year = {{2022}},
}