Solubility and polarity parameters of polyoxyethylene glycol dialkyl ethers.

Solubility parameters were estimated for model individual polyoxyethylene glycol dialkyl ethers and correlated with polarity parameters determined by gas chromatography. The effects of the length of the polyoxyethylene chain and of the terminal alkyl groups on the values of the parameters investigated and on the obtained relationships are discussed. It was found that polarity parameters can be estimated from the total solubility parameter with relatively low errors (approximately 1% for the retention index of ethanol and methanol and for the polarity index of ethanol). The polarity index of methanol and the relative retention of alcohols can be estimated with errors of approximately 3-4%. Using the total solubility parameter, polyoxyethylene glycol dialkyl ethers can be arranged in the same order of increasing polarity as in the case of polarity parameters determined by gas chromatography.