In order to determine hygroscopicity of composites, pre-dried
samples (48 h at 105 ◦C) were placed in sealable containers having
relative humidity levels of 33, 56 and 75%. Moisture absorption of
samples was calculated as the difference between the weight of a
sample recorded after being exposed to humidity until saturation
and the weight of a dried sample (Glenn et al., 2001a,b).