The present disclosure relates to a polyether block polyamide/polydimethylsiloxane (PDMS) composite membrane for gas separation, and a preparation method and use thereof, and belongs to the technical field of membrane separation. In the present disclosure, an amphoteric copolymer PDMS-polyethylene oxide (PEO) (PDMS-b-PEO) is introduced into an intermediate layer to adjust the interfacial binding performance, thereby promoting preparation of an ultra-thin polyether block polyamide composite membrane. Studies have shown that the surface enrichment of PEO segments not only inhibits a dense SiO.sub.x layer formed due to a plasma treatment of a PDMS intermediate layer, but also provides additional hydrophilic sites and interfacial compatibility for the subsequent selective layer. The use of PDMS-b-PEO in an intermediate layer allows the successful preparation of a selective layer with a thickness of about 50 nm.

Membranes, methods of making the membranes, and methods of using the membranes are described herein. The membranes can comprise a gas permeable support layer, an inorganic layer disposed on the support, the inorganic layer comprising a plurality of discreet nanoparticles having an average particle size of less than 1 micron, and a selective polymer layer disposed on the inorganic layer, the selective polymer layer comprising a selective polymer having a CO.sub.2:N.sub.2 selectivity of at least 10 at 57 C. In some embodiments, the membrane can be selectively permeable to an acidic gas. The membranes can be used, for example, to separate gaseous mixtures, such as flue gas.

A polymer composite membrane, a method for fabricating same, and a lithium-ion battery including same are provided. The polymer composite membrane includes a porous base membrane and a heat-resistant layer covering at least one side surface of the porous base membrane, the heat-resistant layer includes a plurality of heat-resistant sub-layers sequentially stacked, and pore-blocking temperatures of the heat-resistant sub-layers are sequentially increased from inside to outside; each of the heat-resistant sub-layers includes at least one of a first heat-resistant polymer material and a second heat-resistant polymer material, and each of the heat-resistant sub-layers is separately configured as a fiber network structure; the melting point of the first heat-resistant polymer material is not less than 200 C.; and the melting point of the second heat-resistant polymer material is not less than 100 C.

A composite semipermeable membrane including: a substrate; a porous supporting layer formed on the substrate; and a separation functional layer formed on the porous supporting layer, in which the separation functional layer contains crosslinked wholly aromatic polyamide as a main component and contains a carboxy group, a ratio of (molar equivalent of the carboxy group)/(molar equivalent of an amide group) in functional groups contained in the separation functional layer is 0.40 or more, and an average ratio of oxygen atoms/nitrogen atoms in front and rear sides of the separation functional layer is 0.95 or less.

The present disclosure relates to a scaling-resistant and yellowing-resistant composite reverse osmosis membrane and a preparation method thereof. By modifying the stability and yellowing of a coating of the reverse osmosis membrane, and grafting 2-(methacryloyloxy)ethyl)dimethyl-3-sulphoproyl) ammonium hydroxide (MEDSAH) and ethylene glycol methacrylate (EGMA) as amphoteric monomers and N-(isobutoxymethyl)acrylamide (IBMA) as yellowing-resistant particles on a surface of the reverse osmosis membrane using active polymerization, the present disclosure forms a three-network high-performance PMEDSAH/PEGMA/PIBMA composite coating. By active regulation of a polyamide (PA) layer through the three systems, the reverse osmosis membrane has high compatibility due to PMEDSAH, and stability, high hydrophilicity and anti-protein fouling property due to PEGMA, as well as yellowing-resistant property by coating PIBMA on the surface. The test results show that the reverse osmosis membrane prepared by the present disclosure has excellent stability and yellowing-resistant property. And the flux and salt rejection are also higher than those of the existing reverse osmosis membranes.

The present specification provides a composition comprising a material of Chemical Formula 1:

##STR00001##

having a molecular weight of 500,000 to 700,000 where R1 and R2 are the same as or different from each other, and each independently is hydrogen, deuterium, or an alkyl group, and n is from 10,000 to 20,000, for forming a reverse osmosis membrane protective layer, a method for preparing a reverse osmosis membrane using the same, a reverse osmosis membrane and a water-treatment module.

The present invention relates to a gas separation membrane including: a supporting membrane; and a separation functional layer which is provided on the supporting membrane and includes a crosslinked polyamide obtained by polycondensation of a polyfunctional amine and a polyfunctional acid halide, in which, in the crosslinked polyamide, the number A of terminal amino groups, the number B of terminal carboxy groups, and the number C of amide groups satisfy (A+B)/C0.66.

Disclosed are an integrated composite filter cartridge (200) and a water purifying system (300) having same. The integrated composite filter cartridge (200) comprises: an outer shell (20), wherein a chamber (21) is defined in the outer shell (20), and the outer shell (20) is provided with a raw water inlet (22), a pre-treated water outlet (23), a pre-treated water inlet (24), a purified water outlet (25) and a waste water outlet (26) which are in communication with the chamber (21); a pre-treatment filter cartridge (100); a central pipe (30); a filter membrane (40); and a control member, which is connected to the pre-treated water outlet (23) and the pre-treated water inlet (24). When the integrated composite filter cartridge (200) is used for the first time, the control member switches on the raw water inlet (22) and the pre-treated water outlet (23) and switches off the pre-treated water inlet (24).

A porous filter includes a porous laminate in which a plurality of biaxially stretched porous sheets made of PTFE are stacked. The Gurley number G and the bubble point B (kPa) of the porous laminate satisfy the following expressions (1) and (2):
log G>3.710.sup.3B0.8(1)
log G<4.910.sup.3B+0.45(2).

A monolithic separation membrane structure comprises a porous monolithic substrate and a separation membrane. The monolithic substrate includes a first end surface, a second end surface and a plurality of through-holes respectively passing from the first end surface to the second end surface. The separation membrane is formed on an inner surface of the respective plurality of through-holes. The surface roughness Ra of the separation membrane is no more than 1 micrometer and the thickness of the separation membrane is no more than 5 micrometers.