A trio of scientists at Osaka University are studying liquids that become solid gels when zapped with an ultrasound and become runny again when heated. Each of the fluids is a mixture of a common solvent with a hairpin-shaped molecule that allows the transformation.
When the molecules are in liquid form, they are like a bunch of people walking around with their hands clasped together. They are free to move around as much as they want. When the molecules form a gel, they are like a bunch of people handcuffed to each other. A group of people or molecules that are locked together will move very slowly, like a gel.
Professor Takeshi Naota and his colleagues described their work in the current issue of Angewandte Chemie International Edition, a leading chemistry journal.
The new chemical could be used to transport toxic liquids without the risk of spilling them. Once scientists understand how this works, they could also design similar molecules for use in automotive transmissions or other machinery. A fluid that thickens and thins on command could be used to temporarily connect the moving parts of a machine to each other without any friction or wear and tear.
