Table 3 shows the water absorption (swelling ratio). The swelling
ratios of different samples were inversely proportional to the
density. All WPC samples measured less swelling than natural
woods and MDF due to the nature of the input components (i.e.,
waste plastics), which encapsulate the palm fiber component as a
barrier to resist the absorption of water by the fiber content. The
application of high compaction pressure (110–120 tons) is another
factor for producing less porosity with higher density. Both the
hard and soft woods and MDF recorded the highest water uptake
because most components in natural wood and MDF are lingo-cellulosic
and hydrophilic in nature