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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
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Second-virial theory for shape-persistent living polymers templated by disks
M Torres Lázaro1, R Aliabadi2, H H Wensink1
1Laboratoire de Physique des Solides, UMR 8502, CNRS, Université Paris-Saclay, 91405 Orsay, France.
Physical Review. E
|December 24, 2021
Summary
Rigid colloidal disks added to living polymers can control their liquid crystal phases. These disks can template polymer nematic phases or disrupt them, leading to complex fluid behaviors and phase separations.
Area of Science:
- Soft Matter Physics
- Polymer Science
- Materials Chemistry
Background:
- Living polymers, formed from noncovalently bonded building blocks, exhibit thermoresponsive lyotropic liquid crystal phases.
- Controlling the self-assembly and phase behavior of these polymers is crucial for advanced material applications.
Purpose of the Study:
- To investigate how rigid colloidal disks influence the liquid crystal phase behavior of living polymers.
- To explore the role of these disks as entropic templates for polymer self-assembly.
Main Methods:
- Utilized a particle-based second-virial theory to model polymer-disk interactions and phase behavior.
- Analyzed entropic contributions from both polymers and colloidal disks.
Main Results:
- Small amounts of discotic additives promote the formation of a polymer nematic phase.
- Higher disk concentrations lead to disruption of the polymer phase and formation of a discotic nematic fluid with dispersed polymers.
- Observed liquid-liquid phase separation coexisting with two nematic phases, indicating four-fluid coexistence in a hard-core mixture.
Conclusions:
- Rigid colloidal disks can act as effective templates to control living polymer liquid crystal phases.
- The study demonstrates complex phase behaviors, including four-fluid coexistence, in mixtures of shape-dissimilar hard particles.
- Provides theoretical insights into conditions for experimental realization of these phenomena.
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