A method for forming an isoporous graded film comprising multiblock copolymers and isoporous graded films. The films have a surface layer and a bulk layer. The surface layer can have at least 1×10.sup.14 pores/m.sup.2 and a pore size distribution (d.sub.max/d.sub.min)) of less than 3. The bulk layer has an asymmetric structure. The films can be used in filtration applications.

A method for forming an isoporous graded film comprising multiblock copolymers and isoporous graded films. The films have a surface layer and a bulk layer. The surface layer can have at least 1×10.sup.14 pores/m.sup.2 and a pore size distribution (d.sub.max/d.sub.min)) of less than 3. The bulk layer has an asymmetric structure. The films can be used in filtration applications.

Described herein is a method of using hollow fiber filter cartridge. The method includes: providing a hollow fiber filter cartridge inside or outside an environmental cleaning equipment; allowing a wastewater to enter the hollow fiber filter cartridge from an outside of the hollow fiber filter under no water pressure or low water pressure (such as under 30 gw/cm.sup.2); allowing the wastewater to cross a plurality of nanopores of the hollow fiber filter cartridge under no water pressure or low water pressure (such as under 30 gw/cm.sup.2) to produce a clean water; and allowing the environmental cleaning equipment to filter wastewater to produce clean water continuously, thereby improving cleaning efficiency and reducing water consumption.

An object of the present invention is to provide a chemical liquid purification method by which a chemical liquid capable of inhibiting the occurrence of short in a semiconductor substrate manufactured by a photolithography process is obtained. Another object of the present invention is to provide a chemical liquid manufacturing method and a chemical liquid. The chemical liquid purification method of the present invention includes a purification step of filtering a liquid to be purified by using a filter, in which a filter satisfying a condition 1 or a condition 2 in the following test is used as the filter. Test: 1,500 ml of a test liquid formed of the organic solvent is brought into contact with the filter for 24 hours under a condition of 23° C., and a content of particles containing at least one kind of metal selected from the group consisting of Fe, Al, Cr, Ni, and Ti in the test liquid after the contact satisfies a predetermined condition.

The invention is in the field of methods for preparing polymer films, and of such polymer films. The method involves phase separation and requires only aqueous solution, eliminating the need for organic solvents. The aqueous phase separation involves contacting a polymer solution comprising a trigger-responsive polymer with an aqueous coagulation solution in which the trigger-responsive polymer is not soluble.

The invention is in the field of methods for preparing polymer films, and of such polymer films. The method involves phase separation and requires only aqueous solution, eliminating the need for organic solvents. The aqueous phase separation involves contacting a polymer solution comprising a trigger-responsive polymer with an aqueous coagulation solution in which the trigger-responsive polymer is not soluble.

A porous membrane includes a triblock copolymer of the formula ABC. B is a hydrogenated vinyl aromatic block present in a range from 30 to 90 weight percent, based on the total weight of the copolymer and has a T.sub.g of ≥110° C. C is a rubbery block present in a range from 10 to 70 weight percent, based on the total weight of the copolymer and has a T.sub.g≤25° C. A is substantially incompatible with both the B and C blocks and is derived from ring-opening polymerization. B+C is present in a range from 70 to 95 weight percent, based on the total weight of the copolymer.

An ultra high molecular weight polyethylene (UHMWPE) membrane has at least one nanoporous UHMWPE film, where each of the nanoporous UHMWPE film is biaxial oriented with a thickness of 0.1 to 12 μm and pores that exclude particles in excess of 10 nm with a total porosity of 65 to 75 percent. The nanoporous UHMWPE film can be coated or laminated by a hydrophilic polymer to form a Janus membrane and can be made with a multilayer composite structure. The UHMWPE membrane can be used in a device for molecular distillation (MD), reverse osmosis (RO), or forward osmosis (FO).

An ultra high molecular weight polyethylene (UHMWPE) membrane has at least one nanoporous UHMWPE film, where each of the nanoporous UHMWPE film is biaxial oriented with a thickness of 0.1 to 12 μm and pores that exclude particles in excess of 10 nm with a total porosity of 65 to 75 percent. The nanoporous UHMWPE film can be coated or laminated by a hydrophilic polymer to form a Janus membrane and can be made with a multilayer composite structure. The UHMWPE membrane can be used in a device for molecular distillation (MD), reverse osmosis (RO), or forward osmosis (FO).

A composite membrane comprising (i) a polymeric membrane panel, said panel having first and second planar surfaces; (ii) a cross-linked adhesive layer disposed on said first planar surface of said polymeric membrane panel, said cross-linked adhesive layer having first and second planar surfaces, where said first planar surface of said cross-linked adhesive layer is in contact with said first planar surface of said polymeric membrane panel; and (iii) an optional release member disposed on said second planar surface of said cross-linked adhesive layer, where said polymeric membrane panel includes a functionalized polymer at said second planar surface.