Chemistry Class: An Introduction to Surfactants

What are surfactants?

Surfactants is actually a short term for 'surface active agent' and is basically a molecule that contains both hydrophilic tail and hydrophobic tail 

Hydrophilic: water loving

Hydrophobic/lipophilic: oil loving, water hating.

So what do they do?

Since they have both these tails, they basically can mix oil and water together. In another word it is also and emulsifier. However, here we are talking about the surfactants we use in wash and shampoo: those that creates bubbles and foam. In that term, because of both this tail, it kind of traps dirt ( can be oily or water based) and clean it up when rinsed. So this is how it works by removing dirt from our body or hair. 

How many types of surfactants are there?

There are 4 main categories of surfactants: 

1) anionic (negatively charged): example: sls, sles, slsa etc

2) amphoteric ( can be both negative and positive charge depending on environment of product:ph, temperatures):-example: cocamidopropyl betaine.

3) non-ionic: example: polysorbate 20, polysorbate 80

4) Cationic: positively charged : example: polyquat-7.

So how do we use them?

Each of these categories offer different kind of properties. Anionic offers a lot of lather and foams. However high usage at times cause dryness ( rating if dryness:5/10), therefore its usually mixed with other surfactants with diff categories.  Amphoteric surfactant adds mildness and viscosity. However it has reduced foam therefore its never use as a primary surfactant. Its always added to anionics. Non ionics doesn't produce foam however it works as great emulsifier to your bubbly product. Adding too much of it will reduce a lot foam in your product. Cationic are conditioning agents. This also reduces foam greatly therefore using 1-3% is sufficient to add as conditioning agent. 

So you see in terms of surfactants itself its a huge topic by itself. I hope this introduction helps you to kickstart on what surfactants are. I will write more about this topic in the future since its my new love interest now to learn more about surfactants:) so till then. Tc..