The POE chain length distribution between the coacervate and aqueous phases of a clouded Triton X-114 solution was studied. The average chain length of the surfactant in the aqueous layer was determined by HPLC and compared to the distribution in the original (unclouded) solution. Both the clouding temperature and the equilibration time were found to govern the chain length selectivity. A slight excess of longer POE chains were encountered in the aqueous layer, thus enriching the coacervate layer with shorter, less soluble chains. Chain length selection appeared to occur when the surfactant particles were dispersed in the clouded suspension, rather than after the establishment of the aqueous and coacervate layers. (C) 2003 Elsevier Science (USA). All rights reserved.