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Stereocomplex Formation of Densely Grafted Brush Polymers
Benjamín R Sveinbjörnsson1, Garret M Miyake1, Amer El-Batta2
1Division of Chemistry and Chemical Engineering, California Institute of Technology, 1200 East California Boulevard, Pasadena, California 91125, United States.
ACS Macro Letters
|May 28, 2022
Summary
Molecular brush copolymers can form stereocomplexes with complementary polymers. However, this complex formation is limited in brush copolymers with critical molecular weight side chains, impacting macromolecular interdigitation.
Area of Science:
- Polymer Science
- Materials Science
- Supramolecular Chemistry
Background:
- Molecular brush copolymers are complex polymer architectures with unique properties.
- Stereocomplexation is a phenomenon where polymers of opposite chirality associate.
- Understanding macromolecular interdigitation is key to designing advanced materials.
Purpose of the Study:
- To investigate the interdigitation of macromolecules within densely grafted molecular brush copolymers.
- To explore the formation of stereocomplexes between complementary linear polymers and brush copolymers.
- To determine the influence of side chain molecular weight on stereocomplex formation in brush copolymers.
Main Methods:
- Utilizing the stereocomplexation tendency between poly(l-lactide) and poly(d-lactide).
- Synthesizing and characterizing densely grafted molecular brush copolymers.
- Analyzing the extent of stereocomplex formation using various analytical techniques.
Main Results:
- Complementary linear polymers and brush copolymers can form stereocomplexes.
- Stereocomplex formation is restricted in complementary brush copolymers.
- Partial stereocomplex formation is observed when side chains reach a critical molecular weight.
Conclusions:
- Macromolecular interdigitation in brush copolymers is influenced by stereocomplexation.
- The molecular weight of side chains critically affects the degree of stereocomplex formation.
- These findings provide insights into controlling polymer assembly in complex architectures.
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