The Chromatographic Separation of Polyoxyethylene Nonylphenyl Ether

Abstract
Polyoxethylene nonylphenyl ether can be separated with respect to the unit of the oxyethylene radical by applying the chromatographic method, using silicic acid as the adsorbent and a chloroform-acetone mixture as the eluent. Nonylphenol was allowed to react with ethylene oxide in the mole ratio of 1:2 in the presence of metallic sodium as a catalyst at the three different temperatures of 190, 140 and 100°C. The chromatographic method was applied to the reaction products, and it was shown that the distribution became somewhat narrower at the lower reaction temperature. A comparison of these results with the theoretical distributions proposed by Flory and by Weibull indicated significant agreement with the latter but a discrepancy with the former. However, when the temperature was rather high, the agreement with the Weibull formula was not good. Similarly, polyoxyethylene nonylphenyl ether having more than two oxyethylene units could be separated by this method. When \barP=10.3, 14 peaks was obtained from a chromatogram. The separation and recovery by this method were considerably better than the distillation method, and a better understanding of the distribution of molecular weights was obtained.