The equal drying time of EA and WPC foams
at such both foam densities was unexpected since the initial
moisture content of WPC foam was much lower than that of EA
foam; the more porous structure of WPC foamwas also expected to
lead to a higher moisture diffusivity (see Section 3.4). However, the
WPC foam had a smaller degree of shrinkage, which lengthened the
diffusion path of moisture traveling from inside to outside of the
sample. Hence, the drying time for the WPC foam was not shorter
than that for the EA foam. The moisture content of EA foam became
almost equal to that of WPC foam at the drying time of 100 min as
shown in Fig. 2. Further increase in the drying time did not lead to
any difference in the moisture content of WPC and EA foams.