| abstract |
The present invention relates to a product having a composite geometry in which hydrophilicity has been imparted to at least a portion of the surface of the article while maintaining the composite geometry almost. Hydrophilicity is imparted by a very thin auto-interlocking sheath of tactile, hydrophilic poly (vinyl alcohol) covering the surface. The tactic poly (vinyl alcohol) precursor applied to the surface of the support structure reacts on the surface with a hydrolysis reagent to produce a tactic, hydrophilic poly (vinyl alcohol) sheath. Products with hydrophilic sheaths have significant resistance to solvents. Hydrophilicity and hydrophobicity can be provided reversibly on the area-specific surface of the product. Products in the form of membranes useful as filters, residue blockers in electroplating devices, separators in electrochemical cells, and drug delivery devices have also been described. Also provided are a film for forming an unmodified, permanent phase, and a method for forming a phase from a phase-forming substrate in an aqueous medium. Hydrophilic porous support structures loaded with substrates, oxygen, and enzyme systems that catalyze the oxygen consumption reaction of moisture as needed, have also been described for application to oxygen removal in packages containing oxygen sensitive products. |