A team of natural scientists has determined the perfect recipe to produce giant soap bubbles. The study revealed that the key component is polymers with varying yarn lengths.
Everyone, regardless of age, loves soap bubbles and the bigger the better. But to make really big soap bubbles the size of a Guinness World Record requires a very precise mix of materials.
Physicists, according to a new publication in Physical Review Fluids, found that a key ingredient in the production of huge soap bubbles is the mixing of polymers with different yarn lengths. This produces a soap film capable of stretching and becoming thin enough to make a giant bubble without breaking.
Soap bubbles, like this article, may seem trivial and ridiculous, but behind their construction there is some complex chemistry and therefore their study has a scientific basis. In the 1800s, the Belgian physicist Joseph Plateau described four basic laws of surface tension that determine the structure of soapy films. The surface tension is responsible for the bubbles being round. This shape has the smallest surface area for a given volume, so it requires the least energy to maintain. Over time, this shape will begin to look more like a soccer ball than a perfect ball, as gravity pulls the liquid down.
Bubbles and foams are still an active area of research. For example, in 2016, French physicists processed a theoretical model for the exact mechanism of how soap bubbles form when a bunch of strong air beats a bar of soap. They found that the bubbles formed only above a certain air velocity, which in turn depended on the width of the air flow.
Soap bubbles are easier to create in a wide airflow and they will be larger in size than those produced in a narrower airflow. The narrower the air flow the harder it is to create bubbles. You can also experiment with the above conclusion if you try to make bubbles with a small plastic ring: the air flow is formed on your lips and is wider than the soap film that floats inside the ring.
What is the perfect recipe for soap bubbles
- 1 liter of water
- 50 ml (milliliters) liquid dishwashing liquid (just over 3 tablespoons)
- 2-3 grams guar gum powder. It is a thickening material used in cooking (about 1/2 teaspoon)
- 50 ml (milliliters) of alcoholic lotion, ie 70% alcohol (just over 3 tablespoons)
- 2 grams of baking powder (about 1/2 teaspoon)
1. Put the guar gum together with the alcohol and mix until there are no lumps.
2. Then add the alcohol / guar pulp together with the water and mix lightly for 10 minutes. Let it sit for a while so that the guar is completely dissolved in the water. Then mix again. The water should thicken slightly, such as thin soup or unwashed gelatin.
3. Add the baking powder and mix.
4. Add the detergent and mix gently to avoid foaming in the mixture.
5. Insert a giant bubble wand into the mixture, holding a thin string, until it is completely submerged and slowly pull the string out. Shake the rod slowly in the air, in one direction only, or tap it to create giant soap bubbles.
Our recipe was provided by Justin Burton, one of the authors of the latest scientific paper and physicist at Emory University who specializes in fluid dynamics. He saw street artists producing giant soap bubbles the size of a hula hoop and the size of a car.
As he stated, he was excited by the change of colors on the surface of the bubbles. This effect of colors is due to the interference created when light reflects the two surfaces of the film. For Burton, this was also an indication that the thickness of the soap was only a few microns (millimeters), roughly equivalent to the wavelength of light. He was surprised that a bar of soap could remain intact as it became so thin and began to do his own experiments, both in the laboratory and in his own home.
Reading it Soap Bubble Wikifound that most preferred bubble solution formulations included a polymer, usually natural guar (a common food thickener) or a medical lubricant (polyethylene glycol).
Using these recipes as a guide, he tried to determine the perfect proportions for a mixture to produce giant bubbles. For their experiments, the researchers created various mixtures of water, soap and polymers. Unfortunately, inflating a 100 m3 bubble is difficult to do in a laboratory and also quite difficult to measure accurately. Soap films were created using a cotton swab and the thickness was measured using infrared light. In addition to measuring thickness, they also monitored the lifespan of each bubble.
Burton and his team concluded that multilateral bonds were the key to producing giant bubbles, confirming the collective internet wisdom. With the right combination, a polymer allows a soap bubble film to reach a "perfect spot" that is viscous but also elastic, so that it does not break.