The present invention relates to a porous ABPBI (phosphoric acid doped poly (2, 5-benzimidazole)) membrane and process of preparing the same. A stable porous ABPBI (Phosphoric Acid Doped Poly (2, 5-benzimidazole)) membrane stable to acids, bases, solvents and autoclaving is disclosed. The membrane finds use for separation of solutes in solution in acids, bases and solvents.

The present disclosure describes a process of obtaining a carbon membrane derived from polymer polybenzoxazine, for improved separation of gases with different kinetic diameters such as helium (2.60 ), hydrogen (2.89 ), carbon dioxide (3,30 ), oxygen (3.46 ), nitrogen (3.64 ), carbon monoxide (3.70 ), methane (3.80 ), ethylene (4.23 ) and ethane (4.42 ) from the molecular sieving mechanism.

Provided is a composite semipermeable membrane, comprising: a microporous support membrane which comprises a substrate and a porous support, and a polyamide separation functional layer formed on the microporous support membrane, wherein the polyamide has an irreversible heat absorption, which is measured using temperature modulated DSC, of 275 J/g or more at a temperature in the range of 20 to 150 C. in the first heating process.

Provided is a high-performance composite semipermeable membrane having high chemical durability, high water permeation and high rejection.

The filtration material includes a supporting layer, a first selective layer disposed on the supporting layer, and a second selective layer disposed on the first selective layer. The first selective layer includes a polyimide and an ionic polymer intertwined with the polyimide. In particular, the polyimide includes at least one repeat unit having a structure represented by Formula (I)

##STR00001##

wherein A.sup.1 is

##STR00002##

A.sup.2 is

##STR00003##

R.sup.1 and R.sup.2 are independently H, CF.sub.3, OH, Br, Cl, F, C.sub.1-6 alkyl group, or C.sub.1-6 alkoxy group; and X and Y are independently single bond, O, CH.sub.2, C(CH.sub.3).sub.2, or NH.

Carbon nanotube membranes that are flexible, non-fragile, stable at high temperatures, superhydrophobic, have submicrometer openings, and are resistant to delamination and corrosive conditions are provided. The carbon nanotube membranes comprise carbon nanotubes grown on a microporous, metal substrate, e.g. silver, quartz fiber filter, and HAST. Methods of fabricating the carbon nanotubes are also provided.

A polyolefin multilayer microporous membrane is disclosed. The polyolefin multilayer microporous membrane has at least three layers, the membrane comprising a first microporous layer composed of a polyethylene resin containing an ultrahigh molecular weight polyethylene (surface layers) and a second microporous layer composed of a polyolefin rein containing a high-density polyethylene and polypropylene (intermediate layer), wherein (I) the pin puncture strength is at least 25 g/m, (II) the coefficient of static friction with respect to a metal foil is at least 0.40, and (III) the meltdown temperature is at least 180 C.

To provide a polyketone porous film having heat resistance and chemical resistance and useful as a filter for filtration having a high particle collection efficiency and as a battery or capacitor separator having a low permeation resistance to ion and the like. A polyketone porous film comprising from 10 to 100 mass % of a polyketone as a copolymer of carbon monoxide and one or more olefins, wherein the polyketone porous film has a pore formed only by a polyketone, the pore diameter uniformity parameter as a value obtained by dividing the standard deviation of the pore diameter in the pore by an average pore diameter is from 0 to 1.0, and the average through hole diameter of the polyketone porous film is from 0.01 to 50 m.

The invention relates to a catalytic activation layer for use in oxygen-permeable membranes, which can comprise at least one porous structure formed by interconnected ceramic oxide particles that conduct oxygen ions and electronic carriers, where the surface of said particles that is exposed to the pores is covered with nanoparticles made from a catalyst, the composition of which corresponds to the following formula:

A.sub.1-x-yB.sub.xC.sub.yO.sub.R where: A can be selected from Ti, Zr, Hf, lanthanide metals and combinations thereof; B and C are metals selected from Al, Ga, Y, Se, B, Nb, Ta, V, Mo, W, Re, Mn, Sn, Pr, Sm, Tb, Yb, Lu and combinations of same; and A must always be different from B. 0.01 <x<0.5; 0<y<0.3.

Perforated graphene sheets can be used in forming separation membranes. Separation membranes of the present disclosure, which can be used in gas separation processes in some embodiments, can include one or more layers of perforated graphene and one or more layers of another membrane material. Methods for separating a gas mixture can include contacting a gas mixture with the separation membranes, and transiting one or more of the gases through the perforated graphene so as to affect separation.

A polyolefin microporous membrane is disclosed. The membrane includes at least one microporous membrane layer, where the microporous membrane layer has an air permeability between about 100 sec/100 cc and about 220 sec/100 cc, a pin puncture strength of at least 550 gf, and a crystallization half time t.sub.1/2 of from 10 to 35 minutes when subjected to isothermal crystallization at 117 C. The air permeability and the pin puncture strength are normalized to a thickness of 16 m.