When you think of the word “ephemeral,” many people immediately conjure up the image of a soap bubble: delicate, adorable, and gone in the blink of an eye (or maybe a few).
Now a team of physicists led by Emeric Rowe of the University of Lille in France has defied these cliches, creating a bubble that has maintained its shape for 465 days.
Although perhaps not as beautiful as the iridescence of the changing luster of soap bubbles, the team’s creation made with the help of glycerol (also known as glycerol) could help scientists develop new materials, such as foams and membranes.
“We have shown that covering the bubble water crust with fine particles prevents gravity-induced drainage, and that adding more glycerol leads to a steady state, in which water evaporation is balanced by the hygroscopicity of glycerol, which absorbs water molecules in the surrounding air,” they write in their papers.
“This results in bubbles that can maintain their integrity in a standard atmosphere for more than one year, with no significant development in radius.”
In general, there are three things that contribute to the short life of the bubble in the atmospheric environment. Gravity can drain the material from the bubble membrane; Evaporation can reduce the amount of liquid present; And the presence of tiny nuclei in the air can destabilize everything.
To see if they could extend the life of the bubble, the team turned to a recent invention called “gas balls”. These are gas bubbles whose shells consist of liquid and partially hydrated particles, surrounded by the surrounding gas.
The particles, usually some type of polymer or plastic, allow the marble to maintain structural integrity even when touched.
Roe and his colleagues wanted to see if they could make gas marbles remain intact for an extended period of time, so they experimented with different types of bubbles. Soap bubbles were included as a point of comparison, and the team also constructed glass spheres from nylon particles, water, nylon particles, and a mixture of water and glycerin.
Soap bubbles, of course, didn’t last long at all—no more than a minute. The water-based gas balls performed best, surviving for periods of 6 to 60 minutes.
On the other hand, hydro glycerine balls held up for an amazingly long time, longer than 101 days, with the longest lasting 465 days.
The team notes that this is the result of adding glycerol. This material is hygroscopic – that is, it readily and readily absorbs moisture from its surroundings or atmosphere.
Nylon particles prevent the bubble film from draining away by gravity; Glycerin, which absorbs moisture from the atmosphere, replenishes what evaporates. When these two phenomena are neutralized, the bubble also becomes impervious to being erupted by those pesky gaseous cores rushing into the air.
This allowed the bubble to maintain its structure for long periods.
“We have shown that air bubbles that maintain their integrity for more than a year can be produced in a simple way by replacing surfactants with partially wetted particles and water with a water/glycerol mixture,” the researchers write.
The team also built a detailed model of the material’s properties, and used that model to create other structures, such as a pyramid stretching over a metal frame, by dipping it in the material and slowly lifting it outward. At least one of the team’s pyramids survived for 378 days at the time they wrote the newspaper.
These remarkable achievements suggest that a whole new class of organisms can be created from this mixture of materials, the researchers note — with physical and chemical properties that we have yet to discover.
The search was published in physical revision fluids.