摘要:
A method of forming a forward osmosis membrane having a porous substrate and a rejection layer is provided. The method comprises a) forming a thin film of a polymer solution on a suitable substrate, wherein the polymer solution contains at least one polymer and optionally one or more additives in a suitable solvent, b) immersing the thin film in a coagulant bath to form the porous substrate; and c) forming a rejection layer on the porous substrate. A forward osmosis membrane is also provided.
摘要:
Disclosed here are semi-permeable cross-linked polyvinyl alcohol (PVA) based membranes that can be used as supports for water purification membranes, and methods for their production. The cross-linked PVA-based membranes are cross-linked with the reaction product of poly-epoxides and —OH groups from the PVA polymers. Methods according to the present disclosure include crosslinking dissolved PVA and dissolved poly-epoxides, casting the cross-linked PVA, and coagulating the cast polymer in a phase immersion precipitation process.
摘要:
The present invention relates to a method for impregnating a filter having pores suitable for retaining particles within them that may be present in a flow of air suitable for passing through the filter, according to which the filter made up of a polymer membrane is impregnated with one or more organometallic salts by applying a treatment using supercritical CO2, the metal M of each salt being chosen from among the group of rare earths, yttrium, scandium, chromium, or a combination thereof. The invention also relates to the obtained filter and an associated method for the collection and quantitative analysis of nanoparticles.
摘要:
Membranes comprising a single layer having a first microporous surface; a second microporous surface; and, a porous bulk between the first microporous surface and the second microporous surface, wherein the bulk comprises a first set of pores having outer rims, prepared by removing introduced dissolvable silica nanoparticles, the first set of pores having a first controlled pore size, and a second set of pores connecting the outer rims of the first set of pores, the second set of pores having a second controlled pore size, and a polymer matrix supporting the first set of pores, wherein the first controlled pore size is greater than the second controlled pore size, and wherein the first and/or second microporous surface comprises a neutrally charged, a negatively charged, or a positively charged, surface; filters including the membranes, and methods of making and using the membranes, are disclosed.
摘要:
A method for producing a porous polyimide film comprises: forming a first un-burned composite film wherein the first film is formed on a substrate using a first varnish that contains (A1) a polyamide acid or a polyimide and (B1) fine particles at a volume ratio (A1):(B1) of from 19:81 to 45:65; forming a second un-burned composite film wherein the second film is formed on the first film using a second varnish that contains (A2) a polyamide acid or a polyimide and (B2) fine particles at a volume ratio (A2):(B2) of from 20:80 to 50:50 and has a lower fine particle content ratio than the first varnish; burning wherein an un-burned composite film composed of the first film and the second film is burned, thereby obtaining a polyimide-fine particle composite film; and a fine particle removal step wherein the fine particles are removed from the polyimide-fine particle composite film.
摘要:
Disclosed is a porous membrane comprising a cellulosic material and a copolymer of the formula: A-B-A (I) or A-B (II), wherein block A, for example, polyglycerol, a polymer of allyl glycidyl ether, or a copolymer of glycidol and allyl glycidyl ether, or a polymer of allyl glycidyl ether or a copolymer of glycidol and allyl glycidyl ether wherein one or more allyl groups having been replaced by hydrophilic groups. Also disclosed is a method for preparing such a membrane.
摘要:
A method for preparing a polymeric material includes: providing a polymeric matrix having at least one polymer and at least one porogen; and degrading the at least one porogen at a temperature T≦1.1 Tg, where Tg is a glass transition temperature of the polymeric matrix. The degrading step includes exposing the polymeric matrix to thermal degradation, chemical degradation, electrical degradation and/or radiation degradation, wherein the polymeric material has a permeability at least 1.2 times a permeability of the polymeric matrix for a gas, and a selectivity of the polymeric material is at least 0.35 times a selectivity of the polymeric matrix for a gas pair. The method preferably provides gas separation membranes that exceed Robeson's upper bound relationship for at least one gas separation pair. Novel polymeric materials, gas separation membranes and fluid component separation methods are also described.
摘要:
Membranes having first and second porous portions, wherein the first portion has a more open pore structure than the second portion, wherein the first porous portion includes pores prepared by removing introduced particles, as well as methods of making and using the membranes, are disclosed.
摘要:
The object of the present invention is concerned with a stimuli-responsive polymer membrane and method of making the same. The method and making the membrane is a new one The entire body of the responsive membrane is a gel. Gels are used as membranes because they are permeable-swollen network. This disclosure discusses a new combination of cylindrical pores in a swollen network. When the network swells or shrinks the cylindrical pores open or close. Thus, inside the network, one can introduce ligands, function groups which due to specific interaction with some signaling molecules in the surrounding environment can cause swelling or shrinking the membrane and this way they open or close pores. With cylindrical pores in a gel there is the ability to regulate pore size in a broad range and an ability to arrange response by adding some functional groups inside the gel body.
摘要:
Microporous materials including a melt-processable, semi-crystalline, thermoplastic (co)polymer, wherein the thermoplastic (co)polymer is miscible in a compatible liquid when heated above a melting temperature of the semi-crystalline thermoplastic (co)polymer, further wherein the microporous material is comprised of a plurality of filaments substantially aligned in a first longitudinal direction, and a mesh extending laterally between the filaments, the mesh comprising a network of interconnected pores having a median diameter less than one micrometer. Methods of making and using such microporous materials (e.g. as films, membranes, battery separators, capacitor separators, fluid filtration articles, separation articles, and the like) are also described.