Alcohol ethoxylates storage stability

The neutralization process consists of an exothermic reaction between a neutralizing agent and either sulfonic acid (e.g., LAB, a-olefins, FAME) or acid sulfate (e.g., primary alcohols, ethoxylated alcohols). Neutralization can be carried out after prolonged storage if the acid stability permits (LAS, FAMES). 

The experimental evaluation [4] of the stability of non-ionic surfactants (nonylphenol ethoxylates, NPEOs, and alcohol ethoxylates, AEOs) during sample storage showed that aqueous samples can be stored at 4°C without addition of any preservative only for a short time (a maximum of 5 days). The most often used preservative is formaline (1-8% (v/v) of 37% solution of formaldehyde in water). 

Several nonionic surfactants, such as the alcohol ethoxylates, can also be used as wetting agents. These molecules consist of a short hydrophobic chain (mostly Cjo) which is also branched a mediumpolyethylene oxide (PEO) mostly consisting of six EO units or fewer is used in this case. The above molecules also reduce the dynamic surface tension within a short time (<20 s) and have reasonably low cmc-values. In all cases, the minimum amount of wetting agent should be used in order to avoid interference with the dispersant that needs to be added to maintain colloid stability during dispersion and storage. 

The stability of these products is governed not only by their composition but also by mechanical factors. The finished product is shear sensitive. From a formulation standpoint, usual actives do not enable the production of storage-stable concentrated products without incorporating emulsifiers such as fatty esters, ethoxylated fatty amines, or amides, and the viscosity must be further adjusted using inorganic salts. Moreover, the formulation of concentrates requires alcohol-reduced grades... 

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