Polyacrylamide (IUPAC poly (2-propenamide) or poly (1-carbamoylethylene), abbreviated as PAM) is a polymer (-CH2CHCONH2-) formed from acrylamide sub-units. It’s highly water-absorbent, forming a soft gel when hydrated.
It has been used in soft contact lenses, along with being used as a filler for facial surgery. In 2013 Yarrock Farms trialed the usage of AG100 SAP ‘Water Jelly Crystals’. These crystals are an example of hydro-gels, which are super absorbent polymers.
Results of the on farm trail can be viewed here
Result of an investigation by Louise Hobbs for '2015 Frontiers in Science International Science Fair' can be viewed here