Abstract: The surface active properties of aqueous solution of the long chain alkoxymethyl crown ethers and corresponding open chain compounds alkoxymethyl oligoethylene glycols, have been investigated by surface tension measurement. The results show that compounds 1 and 2, where the number of carbon atoms in the side chain (n) exceeds 8,can form micelles in aqueous solution, and their CMC values decrease with the increase of n. Correlation of the log(CMC)values of a homologous series of surface active agents for the same temperatare with n gives a satisfactory linear relationship with the correlation coeffecients generally being greater than 0. 99. The effects of NaCl on the surface properties of the long chain alkoxymethyl substituted oligoethylene glycols and corresponding crown ether compounds also have been investigated.

Key words: long chain alkoxymethyl substituted crown ether, surface active property