Surfactant choice

A reexamination of so-called renewabdity has shown that advantages for oleochemicals are not sufftcientiy clear (115), especially because manufacture of surfactants ia the United States accounts for only 0.03% of aimual cmde oil consumption (62). On these bases, the primary determinants of surfactant choice will continue to be cost effectiveness and availability. The 1993 U.S. market has been estimated to be worth 3.7 x 10 (110). Approximately one-half was anionic surfactant ( 1.8 x 10 ) and one-third nonionic surfactant ( 1.2 x 10 ). The balance was made up by cationics ( 1.2 X 10 ) and amphoterics ( 600 x 10 ). The U.S. International Trade Commission (116) provides a minutely detailed breakdown of surfactant production. 

Crofcheck, C., Maiti, I., Pattanaik, S., and Jay, M. (2004). Effect of ion and surfactant choice on the recovery of a histidine-tagged protein from tobacco extract using foam fractionation. Appl. Biochem. Biotechnol. 119(1) 79-92. 

Properties and other criteria influencing surfactant choice... 

Although many factors such as film thickness and adsorption behaviour have to be taken into account, the ability of a surfactant to reduce surface tension and contribute to surface elasticity is among the most important features of foam stabilization (see Section 5.4.3). The relation between Marangoni surface elasticity and foam stability [40-43] partially explains why some surfactants will act to promote foaming while others reduce foam stability (foam breakers or defoamers), and still others prevent foam formation in the first place (foam preventatives, foam inhibitors). Continued research into the dynamic physical properties of thin liquid films and bubble surfaces is necessary to more fully understand foaming behaviour. Schramm et /. [44] discuss some of the factors that must be considered in the selection of practical foam-forming surfactants for industrial processes. Sanders [45] provides a number of surfactant choices and formulation approached for the preparation of non-aqueous foam and non-aqueous aerosol foams. 

BCOABCOA Surfactant Choice 0 (None), A, B, C Base Fluid Choice MM, MDM, or MDDM... 

Economic considerations can often be almost as important as surface activity in selecting a surfactant for a given appUcation. Unless the cost of the surfactant is insignificant compared to the rest of the system, the least expensive material producing the desired effect will usually be chosen. Economics, however, cannot be the only factor in the choice, since the final performance of the system may well be of crucial importance. To make a rational selection, without resorting to an expensive and time-consuming trial-and-error approach, the formulator should have some knowledge of (1) the surface and interfacial phenomena that must be controlled (2) the characteristic chemical and physical properties of the available surfactant choices (3) the relationships between the structural properties of the available surfactants and their effects on the pertinent interfadal phenomena (4) any restrictions to the use of available materials, as in, for example, foods, cosmetics, or pharmaceuticals and (5) economic constraints on the choice of surfactant. 

To a large extent, surfactant choices control the toxicity of raw textile wastewater [39]. Surfactants vary in their aquatic toxicity as well as treatability depending on specific features of the molecular structure. Moore reported that aquatic toxicity correlates with hydrophyllic/lipophyllic balance of the surfactant. He also determined that water hardness is a contributing factor in aquatic toxicity of... 

The choice of surfactant(s) for the formula often has a very direct effect on cleaning, skin irritation, shine, and effort. Surfactant choice has a more indirect effect on surface safety, time, task pleasanmess, and surface conditioning. These aspects are more often controlled by other formula ingredients or even packaging. However, surfactants can also contribute to these as well, as shall... 

We are asked to stabilize stericaUy hydrophobic latex particles using one of the following surfactant choices (i) SDS (sodium dodecyl sulfate), (ii) C10EO5, (iii) NPE15 (i.e. an ethoxylated nonyl phenol with 15 ethylene oxide groups) and (iv) a mixture of 30 wt% C16EO4 and 70 wt% ChEOso- Which surfactant would you use and why ... 

A water-wetting surfactant should not be added beyond a concentration of 1%. Fligh concentrations of surfactant can cause emulsion and foaming problems in production processing equipment. There are many suitable water-wetting surfactants. Choice is not as important as ensuring that one is included in the proper concentration range. 

A Dispersion Resins for dear Applications One of tbe problems with the surfactant coatings normally found on dispersion resins is that they ereate issues with clarity. There are dispersion resins available that use low levels of eare-fuUy chosen surfactants to yield clearer products than those made from typieal dispersion resins. Although careful surfactant choice can help minimize the issues associated with reduced surfactant levels on dispersion resins, plastisols based on these resins are mote likely to require other formulation additives to achieve desired rheological properties than typical plastisol resins. 

The characteristic chemical and physical properties of the available surfactant choices... 

---