Non-ionic Surfactants

Introduction

Non-ionic surfactants, consisting of a hydrophilic head group and a hydrophobic tail, carry no charge and are relatively non-toxic. The hydrophobic moiety of the surfactant may be alkyl (T), fluoroalkyl, or steroidal in nature. A wide variety of hydrophilic head groups are available in vesicle-forming surfactants. There are various types of non-ionic surfactants, such as polyglycerol alkyl ethers, glucosyl dialkyl ethers, crownethers, ester-linked surfactants, polyoxyethylene alkyl ethers, Brij, Spans (sorbitan esters) and Tweens (Polysorbates).

Fig 1. A non-ionic surfactant

Application

Cleaning Products

Some non-ionic surfactants are high foamers (like anionics), while others do not generate much foam. Because of their lower foam profile and strong emulsifying potential, these surfactants are the preferred choice when formulating extraction cleaners and pre sprays.

However, unlike anionic surfactants, non-ionic surfactants are thick liquids or syrups that are sticky or "gooey" to the touch.

Even with that being the case, their importance as cleaners outweighs this negative, and the cleaner or technician must take care to remove as much of the detergent residue as possible from the carpet in order to get the cleaning benefits of non-ionic surfactants without their negatives.

Fig 2. Application in carpet cleaning

In leather production

The demand for non-ionic surfactant in leather production is not very large, while the non-ionic surfactant has a very important significance to improve the quality of leather. Leather production including pretreatment, tanning, leather fatliquoring, dyeing, finishing, and many other links, among them, the non-ionic surfactant is mainly used in tanning and fatliquoring process. The using of non-ionic surfactant polyoxyethylene ether type surfactant may make the touch better, and appear more smooth and more bright colors.

Fig 3. Application in leather production

In coal production

The application of non-ionic surface activity in coal production mainly depends on the quality of coal. The problem of high ash content and humidity in coal determines that non-ionic surfactant is an indispensable chemical raw material for coal production.

Flotation is often used in production, that is, air is injected into the slurry, and then a layer of hydrophobic film is formed on the surface of the coal by adding a certain surfactant. In this way, relatively small coal particles will stick together with the foaming and float to the surface of the coal slurry, so as to obtain high purity cleaned coal. Non-ionic surfactants with low HLB value such as polyol ester are mainly used in coal production.

In pharmaceutical production

In addition to a few special non-ionic surfactants, such as oxidized amine, most of the non-ionic surface activity has the characteristics of dissociation in water, coupled with its toxicity and less hemolysis, therefore, non-ionic surfactant is widely used in medicine as an emulsifier, antioxidant, anticoagulant.

For example, the polyvinyl glycol glycerol can be used as the binder of the troche, and the polyoxyethylene fatty alcohol can be used as the troche lubricant; Non-ionic surfactants such as dehydrated sorbitol, poly (ethylene oxide) type, poly (ethylene oxide) and poly (propylene oxide) block copolymer, can be used as emulsifier for intravenous injection solution, etc.

Fig 4. Application in pharmaceutical production

Reference

1. Thundiparambil Azeez Sonia, Chandra P. Sharma(2014)." 5 - Lipids and inorganic nanoparticles in oral insulin delivery." Woodhead Publishing Series in Biomedicine 2014, Pages 219-256.