Small-angle neutron scattering studies of aqueous solutions of linear alkanediols and triols

We present small-angle neutron scattered intensity measurements in heavy water binary solutions of some short-chain glycols (diols and triols) at room temperature. The spectra were analyzed in terms of a model which takes into account the simultaneous presence of spherical aggregates and concentration fluctuations. We found that hydrated micelle-like aggregates are present in some bi- and trivalent alcohols (e.g., 1,2-hexanediol, 1,2,3-octanetriol) and are absent in others (e.g., 2,5-hexanediol, 1,2,3-hexanetriol). Results are discussed in terms of location of the polar hydroxyl groups in the short hydrocarbon chain. The size and aggregation numbers of the found aggregates are compared with those of other short-chain nonionic surfactants.