Applicability of Weimer‐Cooper’s distribution model for ethoxylated products

The Natta‐Mantica distribution constants characterizing the molecular mass distribution of ethoxylated product mixtures, discussed in an earlier paper, cannot be considered real constants because their values depend on the average degree of ethoxylation (Weibull‐Törnquist effect). As the average degree of ethoxylation is included in the starting equation of the Weimer‐Cooper’s model, it was applied in an attempt to characterize the molecular mass distribution of an ethoxylated fatty alcohol. However, only a qualitative approximation of the distribution was possible with the Weimer‐Cooper’s constants. Consequently, the constants had to be calculated separately from measured mass distribution data. It was demonstrated that the two models predict the same constants when they are in modified form.