When analyzing nonylphenol ethoxylate is analyzed using Asahipak GF-310 HQ (an Aqueous/Organic (multi-solvent use) SEC column), elution characteristics are different according to the degree of POE polymerization because hydrophilicity of the sample is different according to the length of POE chain. For the sample of n=5, a good chromatogram can be obtained with 50 % acetonitrile. However, for the sample of n=10, a poor chromatogram can be obtained with 50 % acetonitrile and a good chromatogram can be obtained with 30 % acetonitrile.


Sample : Nonylphenol ethoxylate, 20 μL
(A),(B) ; 50 ppm
(C) ; 100 ppm

Column       : Shodex Asahipak GF-310 HQ (7.5 mm I.D. x 300 mm)
Eluent       : CH3CN/H2O
Flow rate    : 0.6 mL/min 
Detector     : UV (220 nm)
Column temp. : (A),(B); 30 °C, (C); 40 °C