The present invention provides a separation membrane that is usable at a high temperature and a high pressure. The solvent-resistant separation membrane of the present invention has an average pore diameter of the separation membrane surface of 0.005 to 1 ?m and includes a portion where a degree of cyclization (I.sub.1600/I.sub.2240) as measured by the total reflection infrared absorption spectroscopy is 0.5 to 50.

This disclosure relates to CO.sub.2-philic crosslinked polyethylene glycol membranes useful for natural gas purification processes. Also provided are methods of using the membranes to remove CO.sub.2 and H.sub.2S from natural gas.

A roll-to-roll process and apparatus is disclosed for treatment of a membrane substrate. The apparatus and process processes the membrane substrate in a forward direction using one or more treatment solutions, and then processes the membrane substrate in a reverse direction using other treatment solutions. The treatment solutions used in the forward and reverse directions are preferably chosen so that the treatment sequence is the same in both directions. In this manner, the membrane substrate can accumulate reaction time by repeated processing in forward and reverse directions. t,?

The Invention discloses a preparation method for a triptyl polymer separation membrane, wherein, it comprises the following steps: take triptycene compound containing active group, dichloride compound and diamino compound containing ether bond as monomers, and conduct polymerization in aprotic organic solvent in the presence of acid-binding agent; pour the obtained polymer solution into deionized water for precipitation after the reaction, filter out precipitates and wash with methanol and dry to get triptyl polymer; dissolve the triptyl polymer in aprotic organic solvent to produce a membrane-casting solution, apply the solution on support and dry to get a triptyl polymer separation membrane. The Invention solves the problem that the reticular polymer material is insoluble, and breaks the restriction for application of such material in separation membrane due to its insoluble and aging features.

The present invention deals with a method for obtaining membranes in the form of hollow fibers with application in the field of carbon dioxide removal from natural gas. The aforementioned membranes are obtained by means of heat treatment of polymeric membranes. In this method, polymeric membranes are obtained by a phase-inversion technique by immersion-precipitation and are subsequently subjected to a heat treatment, that is, that the membranes effectively become precursor membranes of the heat treatment. The heat treatment process involves the optimization of the heating rate, temperature, and stabilization time variables, aiming at the improvement of the transport properties of the polymeric membranes. After the heat treatment, it becomes possible to use the membranes in separation processes of gases which operate at pressures greater than 30 bar, with selectivity for carbon dioxide (CO.sub.2).

Provided are a recyclable electret filtering membrane, a preparation method therefor and a cleaning and charge regeneration method therefor. The preparation method includes: dissolving fluorine-containing polymer particles and polyoxyethylene particles in deionized water to prepare a spinning solution, and then performing electrostatic spinning, calcining, cooling, drying and corona charging to obtain the recyclable electret filtering membrane. A surface of the filtering membrane is subjected to water drop rolling cleaning and friction electrification after dust holding, and then dried to realize charge regeneration and reuse. The filtering membrane obtained in the present invention has an initial surface potential of (?600)-(?950) V, the potential can be regenerated to (?700)-(?1000) V by water drop rolling and electrification after dust holding, the charge recovery rate is 90%-125%, the dust removal rate is 90%-100%, and the filtering efficiency for PM.sub.2.5 is equal to or greater than 94%.

A monolayer membrane containing gelling polymer particles having at least one of a basic functional group and an acidic functional group, and having a thickness of less than 5 m. A composite having a porous carrier and gelling polymer particles having at least any one of a basic functional group and an acidic functional group and filling up the surface pores of the porous carrier. The invention can provide a novel material capable of efficiently separating an acid gas from a mixed gas.

A method of producing a composite for acid gas separation by roll-to-roll process, including: a preparation step for preparing a coating liquid, containing a hydrophilic compound, an acid gas carrier and water, for formation of an acid gas separation facilitated transport membrane; a coating step for coating onto the support the coating liquid for formation at a liquid membrane thickness of 0.3 mm to 3.0 mm; a winding step for drying the coated liquid membrane in a drying oven to form the acid gas separation facilitated transport membrane, and winding around a winding roll the composite formed through formation of the acid gas separation facilitated transport membrane on the support, wherein humidity in a winding step unit in which the winding step is performed is measured to control the humidity to be 10% to 60%, and the winding step is performed under the controlled humidity conditions.

The technology encompassed by the current disclosure generally relates to membrane composites that can be used in acoustic venting assemblies. In one embodiment of the technology disclosed herein, a venting media composite has a microporous membrane layer and a coating on the microporous membrane layer to form a composite. The basis weight of the composite is at least about 0.5% higher than a basis weight of the microporous membrane layer without the coating. In some embodiments the composite has a decreased insertion loss than its membrane-only counterpart.

A porous membrane with a molecular weight cut-off (MWCO) greater than about 10 kDa, and a coating on at least a portion of a major surface of the porous membrane. The coating includes a star polymer having a hydrophobic core and hydrophilic arms, wherein the hydrophobic core contacts the porous membrane.