Start
Dec 20, 2012 - 17:00
End
Dec 20, 2012 - 18:00
Venue
Room 118 (Creativity Hall) Ground Floor Chemical Engineering Department
Event Type
Speaker
Rohan Hule Division of Chemisty and Chemical Engineering California Institute of Technology
Title
Exploring Structure-Property Relations: Side-Group Liquid Crystalline Polymers and Self-Assembled Peptide Hydrogels
Abstract : Quantitative structure-property relations have been developed in two systems that connect molecular structure and chain morphology to bulk properties such as switchability and rheological behavior. Chain conformation of Side-Group Liquid Crystalline Polymers (SGLCPs) block copolymers in which the order of the LC mesogen couples with the flexible backbone has been investigated. Distinct chemistries and coupling are examined that induce the formation of unusually large morphologies displaying spontaneous anisotropy and restructuring across a narrow temperature window. Conformational comprehension of these diblocks opens opportunities in responsive LC interfaces with in-built functionality. Significance of self-assembly environment has been demonstrated using β-hairpin peptides capable of self-assembly and hydrogel formation. The stimuli-responsive self-assembly occurs via a strand interdigitation mechanism resulting in semi-flexible fibrillar networks. Change in the chemistry leads to fibrils with distinct morphologies that affect the bulk rheological behavior of the gels. The gels constitute a model system to study structure-property relations in other semiflexible networks.