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In a companion paper, we put forth a thermodynamic model for complex formation via a chemical reaction involving multiple macromolecular species, which may subsequently undergo liquid–liquid phase separation and a further transition into a gel-like state. In the present work, we formulate a thermodynamically consistent kinetic framework to study the interplay between phase separation, chemical reaction, and aging in spatially inhomogeneous macromolecular mixtures. A numerical algorithm is also proposed to simulate domain growth from collisions of liquid and gel domains via passive Brownian motion in both two and three spatial dimensions. Our results show that the coarsening behavior is significantly influenced by the degree of gelation and Brownian motion. The presence of a gel phase inside condensates strongly limits the diffusive transport processes, and Brownian motion coalescence controls the coarsening process in systems with high area/volume fractions of gel-like condensates, leading to the formation of interconnected domains with atypical domain growth rates controlled by size-dependent translational and rotational diffusivities.
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Late Stage Domain Coarsening Dynamics of Lamellar Block Copolymers
The block copolymer (BCP) phase separation is an intriguing phenomenon, the dynamics of which can be expected to differ significantly from that of the polymer blends due to the chain connectivity constraints. The BCP phase separation dynamics has been studied theoretically, but there has been little experimental evidence to confirm the BCP domain growth scaling laws put forward by theoretical studies. Here, we demonstrate the dynamics of late-stage lamellar BCP domain coarsening and show that the scaling exponent for domain growth is ≈1/6 (0.17) irrespective of the annealing temperature, which is close to the scaling exponent of 0.2 shown by theoretical studies. Furthermore, we show that the pre-factors in the domain coarsening equation show Arrhenius dependence on temperature indicating that the BCP domain growth dynamics is Arrhenius.
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- Award ID(s):
- 1905996
- PAR ID:
- 10233587
- Editor(s):
- Segalman, Rachel
- Date Published:
- Journal Name:
- ACS Macro Letters
- Volume:
- 10
- ISSN:
- 2161-1653
- Page Range / eLocation ID:
- 727 to 731
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acsmacrolett.1c00105
