A polysulfone membrane is modified so that monomers are grafted onto the surface of the membrane. The polysulfone membranes can be grafted by contacting the membrane with a grafting solution and exposing the membrane to electromagnetic radiation, typically within the ultraviolet portion of the spectrum. The monomers that are grafted are typically anionic or cationic. The grafted membranes can be used for filtering impurities, such as positively and negatively charged particles, from a liquid. Anionic membranes provide improved filtration of negatively charged impurities, while cationic membranes provide improved filtration of positively charged impurities.

The invention relates to a virus filter membrane which can be used for the removal of virus particles including parvovirus. The invention further relates to a method for producing the membrane. The membrane comprises polyacrylonitrile and polyvinylpyrrolidone.

A composite membrane comprising: a) a porous support; b) a gutter layer; and c) a discriminating layer;
wherein at least 10% of the discriminating layer is intermixed with the gutter layer.

Novel block copolymers comprising at least one (poly)2-C.sub.1-3alkyl-2-oxazoline block and at least one (poly)dimethyl siloxane block, having at least one end group X which includes both an NH.sub.2 group and an NH group, have been found to be particularly suitable for forming vesicles. The vesicles may be used to form filtration membranes.

A composite membrane for selectively separating (e.g., pervaporating) a first fluid (e.g., first liquid such as a high octane compound) from a mixture comprising the first fluid (e.g., first liquid such as a high octane compound) and a second fluid (e.g., second liquid such as gasoline). The composite membrane includes a porous substrate comprising opposite first and second major surfaces, and a plurality of pores. A pore-filling polymer is disposed in at least some of the pores so as to form a layer having a thickness within the porous substrate. The composite membrane further includes at least one of: (a) an ionic liquid mixed with the pore-filling polymer; or (b) an amorphous fluorochemical film disposed on the composite membrane.

The present invention is directed to a method of sealing the free end of a hollow fiber membrane for use in a single header filtration module by dipping the end of the membrane into a low-viscosity light-curable adhesive and curing the adhesive. The invention further encompasses the resulting sealed hollow fiber membrane with a diameter that is only slightly larger than the diameter of the unsealed membrane.

An article that can be used for biomaterial capture comprises (a) a porous substrate; and (b) borne on the porous substrate, a polymer comprising interpolymerized units of at least one monomer consisting of (1) at least one monovalent ethylenically unsaturated group, (2) at least one monovalent ligand functional group selected from acidic groups, basic groups other than guanidino, and salts thereof, and (3) a multivalent spacer group that is directly bonded to the monovalent groups so as to link at least one ethylenically unsaturated group and at least one ligand functional group by a chain of at least six catenated atoms.

The present disclosure discloses a method of fabrication of free standing open pore membranes with uniform pore size and shape and ordered pore distribution, and its use for synthesis of nanoparticle patterns. The method includes applying a photoresist layer to the top surface of a substrate, heating the photoresist layer for a period of time, and exposing the photoresist layer to a dose of ultraviolet radiation through a mask having a predetermined pattern. The dose of ultraviolet radiation is controlled in intensity and time and the photoresist layer is exposed such that a top portion of the photoresist layer through which the dose of ultraviolet radiation enters the photoresist layer undergoes greater cross linking than a bottom portion of the photoresist layer immediately adjacent to the top surface of the substrate such that a cross linking gradient develops through a thickness of the photoresist layer. The mask is removed and the membrane is readily detached from the top surface of the substrate since the portion of the membrane adjacent to the top surface is less cross linked than the top surface of the membrane. The detached membrane forms a free standing patterned membrane having a preselected pattern of open pores. The method can be used with positive photoresist materials as well when deposited on a UV transparent substrate so that the photoresist can be exposed to UV from its top with photomask and UV exposure from its back of the transparent substrate without the photomask.

A method for preparing an ionically-charged membrane comprising the steps (1) applying a film of curable composition to a support; (2) curing the film of curable composition to give anionically-charged membrane; and (3) removing the ionically-charged membrane from the support; wherein the curable composition comprises a) 5 to 50 wt % of curable compound comprising one ethylenically unsaturated group and anionic group; b) 10 to 70 wt % of crosslinking agent comprising at least two ethylenically unsaturated groups and having a molecular weight of at least 500 dalton per ethylenically unsaturated group; and c) 5 to 60 wt % of inert solvent.

Described are hydrophilic polymers (including in the form of a filter membranes that includes hydrophilic polymer) having pendant ionic groups; to methods of making the hydrophilic polymer with pendant ionic groups and derivative membranes and filters; and to method of using the filter membranes for filtering a fluid such as a liquid chemical to remove unwanted material from the fluid.