An increase in either Cu(2+) ion concentration or cross-linking time led to hydrogels with more densely-cross-linked networks that limited water absorption.
This should be done on a porous yet slick-surface material such as Hollytex, Reemay or Pellon and allowed to air dry.
It is well known that a pore former may be used to provide desired porosity of the vacuum molded mat of metal fibers. Fine particles of methyl methacrylate is a prominent example of pore former. The pore former is dispersed like the metal fibers in the viscous aqueous solution of cellulose ether. By heating the vacuum molded layer or mat of metal fibers deposited on the foraminous support, the methyl methacrylate is eliminated by vaporization and combustion.