Thermally Induced Nanoimprinting of Biodegradable Polycarbonates Using Dynamic Covalent Cross-Links
Wiriya Thongsomboon1, Mark Sherwood1, Noel Arellano1
1IBM Almaden Research Center, 650 Harry Road, San Jose, California 95120, United States.
ACS Macro Letters
|May 18, 2022
Summary
Researchers developed dynamic polymer materials using reversible covalent bonds. These polymers form cross-linked films via thermally triggered Diels-Alder reactions, enabling applications in responsive materials and nanoscale patterning.
Area of Science:
- Polymer Chemistry
- Materials Science
- Organic Chemistry
Background:
- Reversible covalent bonds create robust yet dynamic polymeric materials.
- These materials can respond to external stimuli.
- Diels-Alder reactions offer a pathway for reversible cross-linking.
Purpose of the Study:
- To synthesize aliphatic polycarbonate polymers with pendant furanyl and maleimido groups.
- To achieve thermally induced cross-linking via Diels-Alder chemistry.
- To demonstrate the dynamic nature of these cross-linked polymers through nanoscale patterning.
Main Methods:
- Ring-opening polymerization of cyclic carbonate monomers.
- Utilizing a protected maleimido group (furan adduct) for controlled cross-linking.
- Employing diazabicyclo[5.4.0]undec-7-ene and thiourea cocatalyst for copolymer synthesis.
- Thermal nanoimprint lithography for pattern transfer.
Main Results:
- Successful synthesis of random and block copolymers containing Diels-Alder moieties.
- Formation of uniform polymer films capable of bulk cross-linking.
- Demonstration of reversible cross-linking triggered by thermal cycling.
- Successful nanoscale pattern transfer using thermal nanoimprint.
Conclusions:
- Aliphatic polycarbonates with pendant Diels-Alder functionalities can be synthesized.
- Thermally reversible cross-linking is achievable, leading to dynamic polymer networks.
- These materials show potential for applications in stimuli-responsive systems and advanced patterning techniques.
