A composite membrane comprising: a) a first layer comprising a first porous support and a first ionic polymer present in the pores of the first porous support; b) a second layer comprising a second porous support and a second ionic polymer present in the pores of the second porous support; c) a third layer comprising a third porous support, a third ionic polymer and a fourth ionic polymer, wherein the third ionic polymer is present in the pores of the third porous support; wherein: (i) one of the first ionic polymer and the second ionic polymer is a cationic polymer and the other is an anionic polymer; (ii) the third layer c) is interposed between the first layer a) and the second layer b); (iii) the third ionic polymer comprises a network of pores and the fourth ionic polymer is present within the pores of the third ionic polymer; and (iv) one of the third ionic polymer and the fourth ionic polymer is a cationic polymer and the other is an anionic polymer.

A preparation method of a gradient long-effective catalytic membrane with high-strength and anti-deposition property is provided and includes: adding a nanometal oxide catalyst into an N, N-dimethylformamide solution of polyacrylonitrile or polystyrene, uniformly mixing, performing electrostatic spinning, keeping a receiver at −190° C. to −200° C. in the electrostatic spinning process, and performing freeze drying on a precursor membrane obtained after the electrostatic spinning is finished, so as to obtain the gradient long-effective catalytic membrane. According to the method, the gradient long-effective catalytic membrane with high-strength and anti-deposition property is obtained through a one-step method which adopts an ultralow-temperature-electrostatic spinning technology and combines with nanometal, the contradictory relation between the catalytic efficiency and the membrane stability in a traditional catalytic membrane is solved, the catalytic performance of the membrane is fully played, the organic polluted wastewater can be efficiently catalytically degraded, and the service life of the catalytic membrane is prolonged.

A preparation method of a gradient long-effective catalytic membrane with high-strength and anti-deposition property is provided and includes: adding a nanometal oxide catalyst into an N, N-dimethylformamide solution of polyacrylonitrile or polystyrene, uniformly mixing, performing electrostatic spinning, keeping a receiver at −190° C. to −200° C. in the electrostatic spinning process, and performing freeze drying on a precursor membrane obtained after the electrostatic spinning is finished, so as to obtain the gradient long-effective catalytic membrane. According to the method, the gradient long-effective catalytic membrane with high-strength and anti-deposition property is obtained through a one-step method which adopts an ultralow-temperature-electrostatic spinning technology and combines with nanometal, the contradictory relation between the catalytic efficiency and the membrane stability in a traditional catalytic membrane is solved, the catalytic performance of the membrane is fully played, the organic polluted wastewater can be efficiently catalytically degraded, and the service life of the catalytic membrane is prolonged.

Described are filter materials including a polyol ligand, such as n-methylglucamine, and/or a polyphosphonic acid ligand, which are highly effective for filtering metals or metal ions from fluids. The filter materials can be particularly useful to filter basic and acidic fluid compositions, such as those used for wet etching, removing photoresist, and cleaning steps in microelectronic device manufacturing.

A substrate for use in a filter media including, for example, in a hydrocarbon fluid-water separation filter; methods of identifying the substrate; methods of making the substrate; methods of using the substrate; and methods of improving the roll off angle of the substrate. In some embodiments, the substrate includes a hydrophilic group-containing polymer or a hydrophilic group-containing polymer coating.

A membrane comprising: a) a first layer comprising a first polymer or a fourth polymer having ionic groups of polarity opposite to the polarity of the ionic groups of the third polymer; b) a second layer comprising a second polymer having ionic groups of polarity the same as the polarity of the ionic groups of the third polymer; and c) a third layer comprising a co-continuous polymeric network of (i) a third polymer having ionic groups and a network of pores; and (ii) a fourth polymer having ionic groups of polarity opposite to the polarity of the ionic groups of the third polymer; wherein layer c) is interposed between layer a) and layer b) and the third polymer is obtainable by a process comprising phase separation of the third polymer from a curable composition used to prepare the third polymer.

In particles removal with extremely high filtration efficiency and the ability to block submicron airborne particles by a sieving mechanism is provided. This novel nanoporous filter advantageously combines extremely high transmittance for visible light and ultraviolet light, reusability after cleaning or disinfection by ultraviolet irradiation or simple washing, a customizable sieving pore size ranging from a few nanometers to 500 nanometers, and the ability to carry bactericidal, virucidal or other reagents or particles on the nano or micro scale.

A method of manufacturing a PVDF composite separation membrane according to an embodiment of the present disclosure has advantages in that it is possible to control the size of pores in various ways based on the nonsolvent-induced phase transition process and calcination process, and manufacture a porous high-strength PVDF composite separation membrane having high water permeability, and it is possible to manufacture a PVDF composite separation membrane which may exhibit durability that does not damage the membrane even under high pressure, while having heat resistance applicable even at a high temperature of 150° C., and excellent chemical resistance to acids and alkalis, and suppress heavy metal adsorption and biofouling phenomenon, and may allow an organic material to be decomposed by ultrasonic waves or UV photocatalysts. In addition, the PVDF composite separation membrane has excellent mechanical, thermal and chemical resistance properties, suppresses the biofouling phenomenon, and exhibits high ultrasonic reactivity.

Provided is a laminate having low air permeability and excellent moisture permeability. A laminate 1 is provided with a porous substrate 11 and a moisture-permeable membrane 12 disposed on at least one side 11a of the porous substrate 11, the moisture-permeable membrane 12 being formed of a resin having an attraction value relative to water of -110 kcal/mol or less and a repulsive value relative to water of 35 kcal/mol or greater, the attraction value relative to water being a negative integral value while the repulsive value relative to water being a positive integral value in an energy histogram of a combination of solute and solvent obtained from a process of calculating free energy based on energy representation.

The present invention relates to the field of composite membrane and discloses a polyurethane/polyvinylidene fluoride composite membrane for extracting organic sulfide from naphtha. The polyurethane/polyvinylidene fluoride composite membrane includes an active layer and a support layer where the active layer is a polyurethane casting membrane and the support layer is a polyvinylidene fluoride membrane. The polyurethane/polyvinylidene fluoride composite membrane is prepared by coating the active layer onto the support layer. At the same time, a preparation method for the polyurethane/polyvinylidene fluoride composite membrane is disclosed. The present invention has the following beneficial effects: the polyurethane/polyvinylidene fluoride composite membrane prepared in the present invention may be used to extract organic sulfide in naphtha with high separation efficiency. Further, the composite membrane almost does not change the octane number and the like of the raw material oil, thereby improving the extraction rate of the organic sulfide.