The present invention relates to an evaporation retardant membrane for odorant compositions, which comprises a sheet-like support permeable to odorants, and at least one polymer coating arranged on one surface of the sheet-like support, wherein the sheet-like support is permeable to fragrances and where on at least one surface of the sheet-like support at least one polymer coating is arranged only on a part of the surface of the sheet-like support, such that the total coverage of the surface by all polymer coatings is 10 to 90%, and each quarter square centimeter of said surface is covered by a polymer coating to an extent of at least 10%. The present invention also relates to a device for controlled release of an odorant composition comprising a container for receiving an odorant composition, where the container has an opening, which is covered by the evaporation retardant membrane and the use of such a device for controlled release of odorant compositions.

A graft copolymer including zwitterionic repeat units and hydrophobic repeat units, in which the zwitterionic repeat units constitute 2-60 wt % of the graft copolymer and each of the hydrophobic repeat units is characterized in that a homopolymer formed thereof is miscible with polyvinylidene fluoride, polysulfone, poly ether sulfone, polyvinyl chloride, or polyacrylonitrile, each of the hydrophobic repeat units not being a repeat unit of polyvinylidene fluoride. Also disclosed is a filtration membrane containing such a graft copolymer or a statistical copolymer that includes the same composition of repeat units as the graft copolymer. Further disclosed are methods of preparing the graft copolymer and the filtration membrane.

A separation membrane, such as for pressure-assisted oil and water separation. The membrane includes a porous substrate layer and an active layer arranged over at least a part of the substrate layer. The active layer is at least partially crosslinked and comprises a superhydrophilic agent. Also described is a method of producing the separation membrane and a drain valve comprising the membrane.

A separation membrane, such as for pressure-assisted oil and water separation. The membrane includes a porous substrate layer and an active layer arranged over at least a part of the substrate layer. The active layer is at least partially crosslinked and comprises a superhydrophilic agent. Also described is a method of producing the separation membrane and a drain valve comprising the membrane.

Described herein are separation articles such as, for example, films, membranes and the like separating at least one component from a gaseous mixture comprising two or more components comprising difluoromethane (HFC-32, CH.sub.2F.sub.2) and pentafluoroethane (HFC-125, C.sub.2F.sub.5H). The disclosed articles include a “selective layer” that is selectively permeable for the desired component to be separated from the gas mixture. The selective layer is composed of an amorphous fluorinated copolymer. Optionally, the article may include other layers which serve various purposes such as, for example, a porous support layer, a “gutter layer,” which allows the permeate gas to pass from the selective layer to the porous layer with minimal flow impedance, and a protective layer, which protects the selective layer from fouling. Each component of the separation articles described herein and methods for making and using the same are provided below.

Disclosed herein are ladder polymers comprising fused aromatic and non-aromatic rings. Also disclosed are the manufacture and use of these ladder polymers, e.g., in separation membranes, such as membrane for gas separation.

Disclosed herein are ladder polymers comprising fused aromatic and non-aromatic rings. Also disclosed are the manufacture and use of these ladder polymers, e.g., in separation membranes, such as membrane for gas separation.

Hollow fiber membranes, membrane contactors, and related production and use methods. The asymmetric hollow fiber membranes include a porous substrate having a multiplicity of pores and including at least one semi-crystalline thermoplastic polyolefin (co)polymer. A skin layer including at least one polydiorganosiloxane polyoxamide copolymer overlays the porous substrate. The skin layer is less porous than the porous substrate and forms an outer surface of the asymmetric hollow fiber membrane, while the porous substrate forms an inner surface of the hollow fiber membrane. The skin layer is preferably nonporous.

Hollow fiber membranes, membrane contactors, and related production and use methods. The asymmetric hollow fiber membranes include a porous substrate having a multiplicity of pores and including at least one semi-crystalline thermoplastic polyolefin (co)polymer. A skin layer including at least one polydiorganosiloxane polyoxamide copolymer overlays the porous substrate. The skin layer is less porous than the porous substrate and forms an outer surface of the asymmetric hollow fiber membrane, while the porous substrate forms an inner surface of the hollow fiber membrane. The skin layer is preferably nonporous.

Described herein are water desalination membranes and methods of desalinating water. Sulfonated poly(arylene ether) polymers are also disclosed, including those comprising one or more sulfonate groups at various points along the polymer chain. The polymers may be used as at least a portion of a water desalination membrane. The polymers described herein are useful for preventing transport of aqueous ionic species (e.g., Na.sup.+ and Cl.sup.−) across a membrane made from the polymers while allowing water to pass. Chlorine-stable polymers are described, as well as polymers exhibiting good performance for rejecting monovalent cations in the presence of polyvalent cations.