polyethylene glycol MW 6000 wt% log P (dynes/cm^2) 10.0 6.23 15.0 6.51 20.0 6.79 25.0 7.02 30.0 7.23 35.0 7.43 An equation that fits this data is the following. log P = a + b * (wt%) ^ c where a = 5.12, b = 0.28 and c = 0.59 Note that it should be applied only over the range of pressures measured.