How diapers use quantum physics to attend to nature’s call

Sub: Science and tech

Sec: Awareness in IT and computer

What is Quantum Physics?

Quantum computing is a multidisciplinary field comprising aspects of computer science, physics, and mathematics that utilizes quantum mechanics to solve complex problems faster than on classical computers.
The field of quantum computing includes hardware research and application development.
Quantum computers are able to solve certain types of problems faster than classical computers by taking advantage of quantum mechanical effects, such as superposition and quantum interference.

The case of cotton:

Whether something absorbs or repels water has to do with microscopic forces and the nature of a material.
Its smallest constituent is a molecule made of two hydrogen atoms and one oxygen atom.
While every atom here is charge neutral — i.e. it has an equal number of positively charged protons and negatively charged electrons — something funny happens.
Two electrons, one each from every hydrogen atom, decide to shift a bit towards the larger oxygen atom.
The oxygen atoms become more negatively charged and the hydrogen atoms become more positively charged.
When you place your cotton handkerchief on the water you accidently spilled on the table, the water molecules meet the molecules of the cotton fibers.
These fibers are big networks of molecules called polymers, and they have a bunch of slightly positive and negatively charged ions sitting everywhere.
So as soon as you place the cotton on the water, the water molecules see this big network like a bunch of hungry monkeys meeting a jungle of dense trees.
The water molecules now experience forces leading them to rush to the ions, climbing over various molecules of cotton.
In the process the water is soaked up and your handkerchief becomes wet.
This also means that whether some material will soak or not soak water depends on the kind of ions it is made of.
Cotton absorbs water quite well and therefore it is no wonder you see it everywhere, including as cotton balls in the handy medical kit.

Working of a diaper:

Cotton works great when you need to absorb small amounts of water, but when you need to absorb the liters of fluids your baby is producing overnight, clearly something more remarkable is required. This magic material is called a super-absorbent polymer (SAP).
The molecular structure of this compound again resembles the complicated mesh of a tree.
As soon as it comes in contact with water, water molecules flow through and sit inside.
The oxygen atoms in particular are attracted to the mesh due to the presence of an important ion in SAP called sodium — the same sodium that is in your salt and often goes off the charts if you don’t hydrate yourself properly in the summer.
Sodium and water have some unspeakable love for each other that they remain stuck together when given a chance.
This is the same reason salt in the form of a compound of sodium and chlorine dissolves in water. Sodium ions leave the chlorine ions for water molecules, and in the process the salt dissolves.
Because of the oxygen, the water molecules go and attach themselves to the sodium ions in the SAP trees.
They start to hold each other and form a strong network that can no longer move, i.e. it is rigid.
The whole network swells, trapping the water molecules within, to form what is called a gel.
SAP is a magical compound that can absorb a large amount of water, at times more than its own weight.

Quantum physics in the fray:

The reason why sodium and oxygen atoms want to come closer is that they wish to share an electron.
The electron is really a wave, and it can be shared by two atoms at the same time thanks to the rules of quantum physics.
Nature prefers this arrangement to have the electron to live in the shared world of oxygen + sodium and this is what drives water molecules towards the sodium ions in a diaper.