Engineered porous materials, which have fast absorption of liquids under global constraints (e.g. volume, surface area, or
cost of the materials), are useful in many applications including moisture management fabrics, medical wound dressings,
paper-based analytical devices, liquid molding composites, etc.. The absorption in capillary tubes and porous media is
driven by the surface tension of liquid, which is inversely proportional to the pore size. On the contrary, the ability of
conduction (or permeability) of liquid in porous materials is linear with the square of pore size. Both mechanisms
superimpose with each other leading to a possibility of the fastest absorption for a porous structure.
In this work, we explore the flow behaviors for the fastest absorption using heterogeneous porous architectures, from
two-portion tubes to two-layer porous media. The absorption time for filling up the voids in these porous materials is
expressed in terms of pore size, height and porosity. It is shown that under the given height and void volume, these two-component
porous structures with a negative gradient of pore size/porosity against the imbibition direction, have a faster
absorption rate than controlled samples with uniform pore size/porosity. Particularly, optimal structural parameters
including pore size, height and porosity are found for the minimum absorption time. The obtained results will be used as
a priori for the design of porous structures with excellent water absorption and moisture management property in various
fields.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.