We present two classes of polymeric organogels here. First, peptide block copolymer organogels were produced consisting of poly(Z-lysine) through a polymerization-induced gelation process in THF. In these systems, the protecting group on the P(Lys) side-chains remains intact. As such, the secondary structure of the polypeptide chains retains beta-sheet character over a wide range of solution conditions. Gel formation in these systems results from the assembly of the solventphobic P(Lys(Z)) chains, which pack densely in an anti-parallel fashion, minimizing interfacial curvature. In the second system, we describe a new method for the facile, one-pot synthesis of polymeric organogels through modification of Jeffamine polymers with diisocyanate. This precursor can then be dissolved in the desired liquid phase and, upon addition of an amine, gelled. This study will present the mechanism by which gelation takes place in Jeffamine-based materials and determine how factors such as polymer backbone (R1), diisocyanate spacer (R2), amine capping agent (R3) and solvent polarity affect mechanical properties. Throughout these studies, a quantitative comparison between shear and cavitation rheology will be developed.

Shear and cavitation rheology of polymer organogels

255th National Meeting (2018)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.