Hydrophilic membranes and filters and method for preparing same
AssigneeMinnesota Mining and Manufacturing Company
InventorDavid R. Gagnon
Life of this patent
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Abstract
Articles having a complex geometric configuration have hydrophilicity imparted to at least a portion of surfaces of the articles while substantially retaining the complex geometric configuration. The hydrophilicity is imparted by an extremely thin, self-interlocking shell of tactic, hydrophilic poly(vinyl alcohol) enveloping the surfaces. A tactic poly(vinyl alcohol) precursor applied to surfaces of the supporting structure is reacted in situ on the surfaces with a hydrolysis reagent to prepare the tactic, hydrophilic poly(vinyl alcohol) shell. The article having the hydrophilic shell is highly resistant to solvent washout. Hydrophilicity and hydrophobicity can be reversibly provided on regio-specific surfaces of the article. Articles in the form of membranes useful as filters are also described.
Claims9
A porous membrane having a hydrophilic, polymeric shell, comprising:
- a supporting structure having a complex geometric configuration and surfaces about said structure and an extremely thin, self-interlocking, tactic, hydrophilic poly(vinyl alcohol) shell mechanically enveloping a multiplicity of internal and external surfaces while substantially retaining said complex geometric configuration, wherein integrity of the shell mechanically enveloping said multiplicity of surfaces is imparted by the formation of tie molecules connecting two or more crystallites.
A filter to separate solids from fluids comprising:
- a polymeric membrane comprising a supporting structure having a complex geometric configuration and surfaces about said structure and an extremely thin, self-interlocking, tactic, hydrophilic poly(vinyl alcohol) shell mechanically enveloping a multiplicity of internal and external surfaces while substantially retaining said complex geometric configuration, wherein integrity of the shell mechanically enveloping said multiplicity of surfaces is imparted by the formation of tie molecules connecting two or more crystallites.
Dependencies are inferred from the claim text.