This research has it all: ionic liquids, unusual thermorheological behavior, and is based on renewable resources. How cool is that?
Ionic liquids are a rather sexy research area these days. These materials are simply salts that are liquid at or near room temperature. Unlike the more common salts made from column 1 and 2 cations and column 7 anions which have very high melting points, both of the ions in ionic liquids are made of numerous atoms, often organic, and are able to spread the electric charge around rather than concentrating it on a single atom. This dispersion results in a weaker ionic bond which can then "melt" at lower temperatures. Most commonly, the vapor pressure of the liquids is quite low.
The researchers used an ionic liquid to dissolve guar gum and make a film that is conductive (no surprise there) but also hardens when heated and softens when cooled. All told, that is quite a package of unique properties to have.