Drying of the acidic macroporous resin Lewatit K 2631 has been studied
. Oven drying at 84-112-degrees-C and 0.015 atm water partial pressure
shows that the resin behaves as a fibrous solid. Drying by methanol p
ercolation at 20-degrees-C leads to moisture contents in the resin sli
ghty lower than in the previous method. Finally, oven drying of the re
sin previously washed with methanol shows that the residual water cont
ent increases with increasing amounts of the methanol. Estimates of th
e water-effective diffusivity suggest that the last method gives rise
to a lower polymer shrinkage. The changes in the polymer morphology pr
obably result from the formation of a large number of small pores.