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Updated: Jun 16, 2025
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Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
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Topology Effect on Order-Disorder Transition of High-χ Block Copolymers
Cheng-Yen Chang1, Gkreti-Maria Manesi2, Jiayu Xie3
1Department of Chemical Engineering, National Tsing Hua University, Hsinchu 30013, Taiwan, R.O.C.
Macromolecules
|August 19, 2024
Summary
Block copolymer topology significantly influences self-assembly. Increasing star-block copolymer arms raises the order-to-disorder transition temperature (T_ODT), impacting material properties.
Area of Science:
- Polymer Science
- Materials Science
- Supramolecular Chemistry
Background:
- Block copolymers (BCPs) self-assemble into ordered nanostructures.
- Chain topology is a critical parameter influencing BCP self-assembly behavior.
Purpose of the Study:
- To investigate the impact of chain topology on the self-assembly and order-to-disorder transition temperature (T_ODT) of symmetric polystyrene-polydimethylsiloxane BCPs.
- To establish a structure-property relationship between BCP topology and thermal transition behavior.
Main Methods:
- Synthesis of symmetric diblock, three-arm star-block, and four-arm star-block copolymers.
- Temperature-resolved small-angle X-ray scattering (SAXS) to determine T_ODT.
- Differential scanning calorimetry (DSC) to confirm thermal transitions.
Main Results:
- An increase in T_ODT was observed with increasing arm number (from diblock to four-arm star-block) for BCPs of equivalent arm length.
- Flory-Huggins interaction parameter (χ) was determined using random-phase approximation (RPA) based on T_ODT.
- DSC results corroborated SAXS findings, showing a shift in the order-to-disorder transition to higher temperatures with increased arm number.
Conclusions:
- BCP chain topology is a key factor controlling self-assembly and thermal transitions.
- Star-shaped BCPs exhibit enhanced thermal stability of their ordered phases compared to linear diblock counterparts.
- The findings provide valuable insights for designing BCPs with tailored self-assembly characteristics for advanced material applications.
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