Polysoaps are defined as polymers to whose chain soap molecules are attached. Through the reaction of poly‐2‐vinylpyridine with n‐dodecyl bromide such a polysoap was prepared in which 33.7% of the nitrogens were quarternized. This polysoap exhibited reduced viscosities in aqueous solution which were smaller than those of the parent polymer and of the polysoap in ethanol. The relatively compact structure of the polysoap molecule in water which this indicates is thought to be caused by micelle formation of the soap molecules attached to the polymer chain. This idea is substantiated by the fact that the polysoap acts as a solubilizer for isoöctane in water. Solubilization was measured utilizing the vapor pressure as an indicator for the attainment of saturation. Gram for gram, the polysoap solubilized more isoöctane in water than did the related monosoap, n‐dodecylpyridonium bromide. In contrast to the monosoap, no critical concentration of the polysoap was necessary before solubilization occurred. For polysoap concentrations ranging from 0 to 3%, the solubility of isoöctane was proportional to the polysoap concentration. The efficiency of solubilization over this concentration range was 0.066 gram of isoöctane per gram of polysoap.

The effect of isooctane and n‐dodecane on the reduced viscosity of aqueous solutions of a polysoap, derived from poly‐2‐vinylpyridine (D.P. 2000) by partial quaternization with n‐dodecyl bromide, was determined. It was found that the reduced viscosity of polysoap solutions decreased linearly with added hydrocarbon, indicating that the polysoap molecule coils are contracted by the solubilizate. This contraction is ascribed to an increase in the van der Waals' attractive energy furnished by the solubilized hydrocarbon molecules. When the saturation limit of the hydrocarbon was reached, addition of more hydrocarbon caused no further decrease in the reduced viscosity. This phenomenon furnishes a new method for measuring solubilization of hydrocarbons by polysoaps. Solubilization values of isooctane obtained by this procedure were compared with those found previously by the vapor pressure method. The close agreement confirms the validity of both experimental methods. The efficiency of solubilization and the percentage depression of the reduced viscosity were not sensitive to changes in the polysoap concentration. The following differences in the solubilization behavior of the polysoap toward isooctane and dodecane were observed: (1) isooctane was solubilized to a greater extent than dodecane; (2) the maximum reduced viscosity depression obtainable with isooctane was greater than that obtainable with dodecane; (3) gram for gram, the dodecane was the more efficient at depressing the reduced viscosity.

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A polysoap was prepared from poly‐4‐vinylpyridine by quaternizing 43.4% of the pyridine nitrogens with ethyl bromide and 46.7% with n‐dodecyl bromide. Temperatures considerably higher than 25°C. were necessary to bring the polysoap into solution; but, once prepared, the solutions remained stable when cooled to 25°C. Viscosities measured just after the polymer had dissolved were irreproducible. On further heating, the viscosity decreased, eventually reaching a constant value which was reproducible. The viscosity decreases of three portions of a 0.5% solution was followed at 45°C., 55°C., and 65°C., respectively, and it was found to be fastest at the highest at the highest of these temperatures and slowest at the lowest. The final values reached at all three temperatures were approximately the same. These results are consistent with the assumption that the initially irreproducible viscosities are due to clusters of polysoap molecules which have not had enough time to break up. Prolonged heating is necessary to produce complete dissolution into individual molecules. Once reproducibility was attained it was shown that the polysoap exhibited essentially the same viscosity and solubilization characteristics as had previously been observed for polysoaps derived from poly‐2‐vinylpyridine.

The effect of solubilized benzene on the viscosity of aqueous solutions of a polysoap, derived from poly‐2‐vinylpyridine and n‐dodecyl bromide was found to be different, both in kind and in order of magnitude, from the simple viscosity depression characteristic of solubilized aliphatic hydrocarbons. As the benzene content of a given solution is increased, the viscosity at first rises, reaches a maximum, and decreases again, below its initial value, until the solution is saturated. The maximum rise in the reduced viscosity increases very strongly with increasing concentration of the polysoap, indicating that the viscosity increase is caused by interactions between polysoap molecules. On the other hand, the reduced viscosity depression at benzene saturation is not sensitive to the polysoap concentration and may therefore be ascribed to a contraction of the individual polysoap molecules. Both at the viscosity maximum and at benzene saturation, the respective amounts of benzene solubilized by unit amount of polysoap were found to be independent of the polysoap concentration. These results are interpreted to mean that the polysoap molecules act as independent solubilizing units, but that their structure is changed by the solubilized benzene is such a way as to strongly affect their mutual interaction. Based on the assumption that the benzene is solubilized both in the hydrocarbon and in the ionic regions of the polysoap molecules, a mechanism for the structure changes which would explain the viscosity maxima is suggested.