polyethylene glycol MW 400
wt% log P (dynes/cm^2)
2.5 6.30
5.0 6.55
10.0 6.93
15.0 7.14
20.0 7.33
25.0 7.50
30.0 7.65
An equation that fits this data is the following.
log P = a + b * (wt%) ^ c
where a = 5.29, b = 0.73 and c = 0.34
Note that it should be applied only over the range of pressures measured.