Hydrated gels are very slippery, and we now know it’s partly due to their surfaces! Chris made composite hydrogels with a soft surface skin, then fully characterized the effective stiffness of that layer, contact mechanics, and how it contributes to good lubrication (or not!) He did an impressively-large number of experiments involving materials synthesis, careful […]
Hydrogels are inherently slippery — we know this from touching jello and sliding on banana peels. It’s been shown in many of our prior publications, as well as publications from the Sawyer group (University of Florida), the Spencer group (ETH), the tribology group at Imperial College, and many others. However, making polyacrylamide hydrogels in the […]
While we normally work with single-polymer hydrogels, we had the opportunity to work with the Grunlan group at Texas A&M to study their charged double-network hydrogels. These hydrogels are tough! Looking more like cartilage all the time. In this paper we present evidence that their lubrication behavior matches or exceeds that of native cartilage. Higher […]
Many researchers are aware that hydrogels, even a single kind of hydrogel (polyacrylamide) can be designed to have properties that range from brittle to viscoelastic. It’s truly a versatile material! As hydrogels are being considered as replacements for cartilage in the body, they need to be able to take a beating: they can’t break under […]