The method of making a nanocomposite polyelectrolyte membrane is a process for forming membranes for use in hydrogen and methanol fuel cell applications, for example. A hydrophobic polymer, such as polypropylene, is blended with a nanofiller, such halloysite nanotubes (HNTs) or propylene-grafted maleic anhydride nano-layered silica (Ma-Si), to form a dry mix, which is then pelletized for extrusion in a twin-screw extruder to form a thin film nanocomposite. The thin film nanocomposite is then annealed and cold stretched at room temperature. The cold stretching is followed by stretching at a temperature ranging from approximately 110 C. to approximately 140 C. The nanocomposite is then heat set to form the nanocomposite polyelectrolyte membrane. The nanocomposite polyelectrolyte membrane may then be further plasma etched and impregnated with a sulfonated polymer, such as sulfonated melamine formaldehyde, a polycarboxylate superplasticizer or perfluorosulfonic acid.

A composite polyamide reverse osmosis membrane comprising a polyamide layer; where the polyamide layer has a thickness in the range of 50-250 nm, and large open spaces (i.e., free volumes); where the open spaces are defined by a ratio of water flux, J.sub.w, (gfd) divided by the average surface roughness, Ra, (nm) of the polyamide layer; wherein the composite polyamide reverse osmosis membrane has the ratio of J.sub.w/Ra>0.35 gfd/nm when tested at 65 psi, using an aqueous solution containing 250 ppm of NaCl; and a microporous support with a thickness ranging from 100-150 ?m. The present invention also relates to processes of fabricating the composite polyamide reverse osmosis membrane.

Disclosed embodiments are related to mitigating leaks in membranes and/or improving the selectivity of membranes.

Copolymers including at least one optionally substituted 2-hydroxy-5-sulfonic aniline as a first constituent unit and at least one optionally substituted phenylenediamine as a second constituent unit are disclosed. Compositions containing the copolymers, and methods of making the copolymers are also disclosed. The compositions can also contain for example an ethylene-vinyl acetate copolymer (EVA) and/or electrical conducting additives. The compositions can, for example, be used for detecting lead ions in a sample.

An electrolyte-separating membrane includes a carrier made of a porous and permeable synthetic thermoplastic material that is larger than 0.8 mm in thickness and an active layer made of a material able to induce insertion and deinsertion reactions for selective transfer of cations through the membrane. The active layer is deposited on the carrier and is hermetic. The material of the active layer may in particular be a molybdenum cluster chalcogenide. The invention aims to provide an electrolyte-separating membrane that is able to transfer cations selectively and that may be manufactured with large dimensions. The invention also relates to a cation transfer method employing this membrane and to a process for manufacturing said membrane, in particular by selective laser sintering of a powdered polymer.

The invention relates to a method for producing an anion-exchange polymer material having an IPN or semi-IPN structure, said method consisting in: (A) preparing a homogeneous reaction solution containing, in a suitable organic solvent, (a) at least one organic polymer bearing reactive halogen groups, (b) at least one tertiary diamine, (c) at least one monomer comprising an ethylenic unsaturation polymerizable by free radical polymerization, (d) optionally at least one cross-linking agent including at least two ethylenic unsaturations polymerizable by free radical polymerization, and e) at least one free radical polymerization initiator; and (B) heating the prepared solution to a temperature and for a duration that are sufficient to allow both a nucleophilic substitution reaction between components (a) and (b) and a free radical copolymerization reaction of components (c) and optionally (d) initiated by component (e). The invention also relates to the resulting IPN or semi-IPN material and to the use thereof in electrochemical devices, in direct contact with an air electrode.

A composite structure comprising a layer of zeolite having a high silica to alumina ratio supported on a support layer acts as a separator in a redox flow battery. The zeolite can be either supported on a rigid substrate, such as alumina, or a flexible substrate, such as a polymeric film. The polymeric film, in particular, can be an ion exchange membrane such as Nafion. The zeolite layer with a high silica to aluminum ratio provides a long-lasting separator for redox flow batteries.

The invention relates to a process for preparing a composite material comprising a fluorinated polymeric matrix and a filler consisting in ion exchange inorganic particles comprising a step for in situ synthesis of said particles within the polymeric matrix, said matrix comprising at least one first copolymer comprising at least two types of fluorinated recurrent units, a type of which bears at least one pendant maleic anhydride group.

In a subsystem or water-feed path located upsteam of a use point in an ultrapure water production/supply process, fine particles having a particle diameter of 50 nm or less, in particular 10 nm or less are highly removed. A device for removing fine particles in water has a membrane filtration device including a microfiltration membrane or an ultrafiltration membrane having a weak cationic functional group. The microfiltration membrane or the ultrafiltration membrane having a weak cationic functional group is preferred to have a polyketone film with the weak cationic functional group. Negatively-charged particles in water are adsorbed by the weak cationic functional group and can thus be removed.

A non crosslinked, covalently crosslinked and/or ionically crosslinked polymer, having repeating units of the general formula (1)

KR(1)

In which K is a bond, oxygen, sulfur,

##STR00001##

the radical R is a divalent radical of an aromatic or heteroaromatic compound.