About this Abstract |
Meeting |
2023 TMS Annual Meeting & Exhibition
|
Symposium
|
Frontiers of Materials Award Symposium: Functional Composition Control of Surface Mechanics in Soft, Water-swollen Gels
|
Presentation Title |
Hydrogel Structure and Surface Physics |
Author(s) |
Angela A. Pitenis |
On-Site Speaker (Planned) |
Angela A. Pitenis |
Abstract Scope |
Hydrogels are a class of materials broadly defined as three-dimensional crosslinked networks of hydrophilic polymer chains swollen with water. The mesh size of hydrogel networks (similar to the average distance between crosslinks) is thought to control their mechanical and transport properties. Small-angle X-ray scattering (SAXS) measurements of bulk polyacrylamide (PAAm) hydrogels have given ranges of mesh size between 1 and 10 nm, corresponding to water contents from roughly 88 to 98%. However, recent investigations have suggested that it is the superficial structure of hydrogels that controls surface physics (i.e., adhesion, friction) during contact and sliding. Here, we have shown that PAAm hydrogels may exhibit depth-wise gradients in crosslink density following free-radical polymerization across air-water interfaces which is highly sensitive to environmental oxygen. |
Proceedings Inclusion? |
Planned: None Selected |