Controlling orientation and functionalization in thin films of block copolymers
Chansub Lee1, Seung Hyun Kim, Thomas P Russell
1Division of Nano-Systems Engineering, Inha University, Incheon 402-751, South Korea.
Macromolecular Rapid Communications
|June 4, 2011
Summary
This study introduces a method to control and functionalize block copolymer nanostructures using gold salts. This approach enables precise control over nanostructure orientation and morphology in thin films and solutions.
Area of Science:
- Materials Science
- Polymer Chemistry
- Nanotechnology
Background:
- Controlling nanostructure morphology is crucial for advanced applications.
- Block copolymers self-assemble into ordered nanostructures.
Purpose of the Study:
- To develop a general method for simultaneous functionalization and control of block copolymer nanostructures.
- To investigate the effect of gold salt concentration on nanostructure formation.
Main Methods:
- Thin film preparation of polystyrene-block-poly(vinyl pyridine) (PS-b-PVP).
- Complexation of gold salt with the poly(vinyl pyridine) (PVP) block.
- Solvent annealing of thin films.
- Morphological analysis of solutions and thin films.
Main Results:
- Small gold salt concentrations led to microdomain orientation normal to the surface in thin films via complexation with PVP.
- Increased gold salt concentrations induced micelle formation in solutions.
- A range of morphologies were observed in thin films depending on gold salt concentration.
Conclusions:
- Gold salt complexation offers a versatile route for controlling and functionalizing PS-b-PVP nanostructures.
- The method allows for tuning nanostructure morphology from oriented thin films to various solution-based structures.
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