Hierarchy and architecture - tailoring physical associations toward functional networks and gels
· Invited
Abstract
Taking cues from biological systems, we are interested in understanding how physical associations may be utilized in the design of functional materials: (1) supramolecular networks and elastomers, and (2) peptide-polymer hybrids.
Supramolecular interactions may hold the key to the development of elastomers with a tailored elastic response and improved mechanics, such as observed in the muscle protein titin. We have developed supramolecular elastomers and interpenetrating network systems that probe the interplay of non-covalent and covalent interactions in structural organization and mechanical response. In this research, concepts of interfacial control of self-assembly, composition, and dynamics as it relates to mechanical behavior are examined. Variations in non-covalent interaction strength and network regularity are also highlighted as handles to tune dynamic response and morphology.
The underlying structural blocks of nature’s high-performance materials are polypeptides, which exhibit secondary structures that contribute to the high degree of molecular order observed in biohybrid materials. Polymeric hybrids with a focus on ‘soft’ domain ordering have been designed using a dynamic elastomeric polyurethane/urea framework with poly(dimethyl siloxane) (PDMS) and poly(ethylene glycol) (PEG) soft segments. We explored the impact of peptide chain length/fraction, and secondary structure on mechanics in chain-extended and non-chain extended systems. Extending this work to an overlay of covalent and non-covalent architectures influenced peptide hydrogen bonding and hierarchy. Tailored physical associations between the hard and soft domains yielded functional responses with applications as injectable hydrogels and actuating materials.
Supramolecular interactions may hold the key to the development of elastomers with a tailored elastic response and improved mechanics, such as observed in the muscle protein titin. We have developed supramolecular elastomers and interpenetrating network systems that probe the interplay of non-covalent and covalent interactions in structural organization and mechanical response. In this research, concepts of interfacial control of self-assembly, composition, and dynamics as it relates to mechanical behavior are examined. Variations in non-covalent interaction strength and network regularity are also highlighted as handles to tune dynamic response and morphology.
The underlying structural blocks of nature’s high-performance materials are polypeptides, which exhibit secondary structures that contribute to the high degree of molecular order observed in biohybrid materials. Polymeric hybrids with a focus on ‘soft’ domain ordering have been designed using a dynamic elastomeric polyurethane/urea framework with poly(dimethyl siloxane) (PDMS) and poly(ethylene glycol) (PEG) soft segments. We explored the impact of peptide chain length/fraction, and secondary structure on mechanics in chain-extended and non-chain extended systems. Extending this work to an overlay of covalent and non-covalent architectures influenced peptide hydrogen bonding and hierarchy. Tailored physical associations between the hard and soft domains yielded functional responses with applications as injectable hydrogels and actuating materials.
*The authors gratefully acknowledge financial support from NSF DMR-0953236 and NSF DMR-1608441.
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Presenters
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LaShanda Korley
- Materials Science and Engineering, University of Delaware