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Anionic Polymerization of an Amphiphilic Copolymer for Preparation of Block Copolymer Micelles Stabilized by π-π Stacking Interactions
Published on: October 10, 2016
A theoretical study on the inverted phase formation in diblock copolymer solutions
Haitao Jia1, Haiying Huang, Tianbai He
1State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China.
The Journal of Chemical Physics
|December 20, 2012
Summary
The inverted phase in block copolymer solutions forms due to solvent affinity and block copolymer characteristics. Increasing solvent affinity or size expands the inverted phase window.
Area of Science:
- Polymer Science
- Materials Science
- Physical Chemistry
Background:
- Inverted phases are common in block copolymer (BCP) and preferential good solvent solutions.
- These phases feature a swollen minority block and solvent forming the continuous microdomain.
Purpose of the Study:
- To investigate the formation of inverted phases in A-B BCP solutions using self-consistent field theory.
- To analyze the influence of BCP and solvent parameters on inverted phase formation.
Main Methods:
- Self-consistent field theory (SCFT) was employed.
- Parameters of both the block copolymer and solvent were systematically studied.
Main Results:
- BCP and solvent characteristics significantly influence inverted phase formation.
- Higher Flory interaction parameter (χ(AB)N), increased solvent affinity for the minority block, or larger solvent monomer size enlarge the inverted phase existence window.
- Both enthalpy and entropy contributions of the solvent are crucial for inverted phase formation, with relative importance dependent on solvent molecular size.
Conclusions:
- The study elucidates the key factors governing inverted phase formation in BCP solutions.
- Understanding these parameters allows for better control and prediction of BCP phase behavior.
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