Abstract:
The invention relates to a process for preparing a microporous membrane from an unsulfonated poly(phenylene sulfide) polymer by forming a mixture of an unsulfonated poly(phenylene sulfide) polymer, an amorphous polymer, and optionally a plasticizer, heating the resulting mixture, extruding or optionally casting the mixture into a membrane, controlled cooling (quenching) or coagulating the membrane, and leaching the membrane, while optionally drawing the membrane before, during, and/or after leaching.
Abstract:
The present invention provides a microporous material or a membrane in which the membrane includes an azlactone moiety which is blended with or grafted to a thermoplastic polymer to provide a porous material having an internal structure characterized by a multiplicity of spaced, randomly disposed, non-uniform shaped, equiaxed particles of the polyazlactone polymer/thermoplastic polymer blends or the azlactone-graft copolymer. Each of the adjacent particles throughout the material are separated from one another to provide said material with a network of interconnected micropores and each of the particles are connected to each other by a plurality of fibrils. In addition to unmodified azlactone membranes, membranes which have been modified by subsequent reaction of the azlactone moiety with a suitable nucleophile are also included within the scope of the present invention. Preferred nucleophiles capable of reacting with an azlactone membrane of this invention include biologically significant nucleophiles such as amines, thiols and alcohols as well as amino acids, nucleic acids and proteins.
Abstract:
Microporous membranes and methods for producing such membranes from ultrahigh molecular weight polyethylene. The method employs extrusion of a solution of UHMW-PE and porogen through a forming die followed by thermal phase separation of polymer and porogen. Microporous structures are created by removing porogen. Microporous membranes produced include membranes with good permeability to air and water making them particularly useful as filtration media and water-resistant breathable membranes.
Abstract:
The present invention provides porous particles uniform in shape and having through holes that are not closed. The porous particles according to the present invention are porous particles having a substantially spherical shape. Each of the porous particles has an interconnected pore structure in which through holes provided inside the porous particle communicate with each other, and ends of the through holes are open toward an outside of the porous particle.
Abstract:
The present disclosure provides a method of producing a aerogel comprising of reacting first monomer with a second monomer in a reaction solvent to form a composition comprising a precursor polymer; forming a gel; conducting a solvent exchange process on the gel such that the resulting gel comprises an exchange solvent that has a freezing point; cooling the gel to a temperature below the freezing point of the exchange solvent; and subjecting the cooled gel to vacuum conditions to obtain the aerogel.
Abstract:
A vinyl chloride-based copolymer porous body contains a vinyl chloride-based copolymer as the main component. The vinyl chloride-based copolymer porous body has continuous pores having a pore size of 0.1 to 40 μm, the pores have a skeletal diameter of 0.1 to 20 μm, and the vinyl chloride-based copolymer has a thickness of 1 mm or more. Such a vinyl chloride-based copolymer porous body can be produced by a production method including the steps of: heating and dissolving the vinyl chloride-based copolymer in a solvent to obtain a vinyl chloride-based copolymer solution; cooling the vinyl chloride-based copolymer solution to obtain a precipitated product; and separating and drying the product to obtain a porous body containing the vinyl chloride-based copolymer as the main component.
Abstract:
Provided is a microporous material, e.g., a microporous sheet material, having a matrix of polyolefin, finely-divided, substantially water insoluble particulate filler, a network of interconnecting pores communicating throughout the microporous material, and at least one retrospectively identifiable taggant material embedded within the matrix, optionally the at least one taggant being unique to an end user for the microporous material, wherein the polyolefin is present in the microporous material in an amount of 20 to 35 weight percent, based on the weight of the microporous material. The taggant material provides a marker, signature or code that is capable of retrospective identification by machine, instrument or by the naked eye. Articles including the microporous material and processes for preparing the microporous material also are provided.
Abstract:
A method for removing a process solvent (P-sol) from a polymer extrudate, especially in connection with a process for producing a microporous membrane. The method involves contacting the extrudate with chlorinated hydrocarbon (CHC) and hydrofluoroether (HFE) in a first stage; contacting the extrudate from the first stage with HFE in a second stage; combining the first and second waste streams and then separating the P-sol from the combined streams to make an HFE-CHC stream; cooling the HFE-CHC stream to make an HFE-rich phase and a CHC-rich phase; and conducting the CHC-rich phase and/or the HFE-rich phase to step (A).
Abstract:
A porous object comprising a three-dimensional network skeleton of a cured epoxy resin and having interconnecting pores, characterized in that the three-dimensional network skeleton forms a non-particle-aggregation type porous object constituted of a three-dimensional branched columnar structure, the proportion of aromatic-ring-derived carbon atoms to all the carbon atoms as a component of the cured epoxy resin is 0.10-0.65, and the porous object has a porosity of 20-80% and an average pore diameter of 0.5-50 μm.
Abstract:
The present invention relates to a monolithic organic copolymer prepared by copolymerization of at least one monomer of the group consisting of styrene, (C1-C3)alkylstyrene, (meth)acrylic acid and esters thereof with a crosslinker in the presence of a macroporogen and a microporogen, wherein a) the sum of said at least one monomer of the group and the crosslinker is 10-20%, preferably 10-15%, by volume of the reaction mixture, with the rest being essentially macroporogen and microporogen, and the degree of said copolymerization is at least 70%, preferably at least 90%, more preferably at least 99%, or b) the sum of said at least one monomer of the group and the crosslinker is 30-50%, preferably 35-45%, by volume of the reaction mixture, with the rest being essentially macroporogen and microporogen, and the degree of said copolymerization is in the range of 25-60%, preferably 35-50%. These copolymers can be used in high-performance liquid chromatography for the separation of biopolymers as well as small molecules.