SrCO3 particles were prepared by CO2 bubbling into a solubilization system of aqueous Sr(OH)2 in a cyclohexane solution of hexaoxyethyleneglycol dodecyl ether (DP-6) or polyoxyethylene (6) nonyl-phenyl ether (NP-6). In the both surfactant systems, the shape of particles were changed with the solubilization behavior of aqueous Sr(OH)2. In the DP-6 system, rod and spindlelike particles were formed in the colorless and the blue teranslucent regions, respectively. In the NP-6 systems, on the other hand, spindlelike particles were formed in the colorless region while dendritelike particles were found in the blue translucent region. The size of the spindlelike particles was almost independent of the amount of added aqueous Sr(OH)2 in the both systems. However, it increased with increasing concentration of the surfactants. The effect of the concentration of aqueous Sr(OH)2 on the shape charge of particles was explained by the salting out effect of Sr(OH)2.
Bisphenol A-formaldehyde addition products (resols) were subjected to the reversed-phase high-performance liquid chromatography (HPLC). Separated components from the reaction mixture were analyzed by the infrared, mass and nuclear magnetic resonance spectroscopies for the determination of chemical structures. It was made clear that the separation and the quantitative determination were possible for the reaction mixtures containing unreacted bisphenol A and four kinds of the addition products of bisphenol A reacted with one to four molecules of formaldehyde. On the basis of the analytical technique, the availability of HPLC for the investigation of the reaction scheme in resol formation was studied.