(Fig. 3B). The TiO2 powder is selected because it is chemically and
physically stable and is highly compatible with the polymer and
the mesh. In addition, it can seamlessly fill the gaps to form a thin
intermediate supporting layer, and it does not affect the permeability
of water vapor. A thin permselective layer of hydrophilic
polymer was successfully coated on top of the TiO2 intermediate
layer (Fig. 3C). Fig. 3D shows a thin and flexible synthesized composite
membrane.
The membrane can withstand strong mechanical forces under
varying operating conditions. When low vacuum pressure of
0.1 mbar was applied on one side of the membrane, no physical
damage was detected. The membrane dehumidification performance
can be sustained for three to four months without any
major degradation – physically or performance outcome.