Hydrogels are another class of soft material we are investigating. Hydrogels are typically comprised of a sparse network of cross-linked polymers imbedded in a fluid matrix - one well-known example is Jello. Poly(vinyl alcohol) (PVA) solutions form hydrogels when thermally cycled to 20 °C and back to room temperature, with repeated cycling resulting in stronger gels. This material has applications as a biomaterial ranging from wound dressings to heart valve stents. |
Mechanical properties of PVA hydrogels as a function of thermal cycling |
|
The utility of this hydrogel is enhanced by its ability to form gels with anisotropic mechanical properties when processed under strain. We are using mechanical testing and small-angle neutron scattering (SANS) to determine the gelation mechanism leading to these unusual properties. |
Last updated July 16, 2005