Abstract: Process for making polyisocyanate based aerogels by trimerisation of an organic polyisocyanate in an organic solvent in the presence of a (co)polymer containing an isocyanate-reactive group, gellation and supercritically drying of the obtained sol-gel.

Abstract: A method of producing a polymer packing material for liquid chromatography includes the steps of swelling seed polymer particles to form swelled particles, polymerizing monomers in the swelled particles under existence of diluent, and removing the diluent to form porous polymer particles, wherein the step of polymerizing the monomers is conducted under existence of a compound having a conjugated double bond not reactive with the monomers and having a molecular weight of 100-500. Alternatively, the polymerization process may be conducted by an oxidation reduction polymerization process. Further, the porous polymer particles obtained after removal of the diluent may be subjected to a heat treatment process at a temperature of 100.degree. C. or higher.

Abstract: A first dispersion phase is dispersed in a first continuous phase comprising a solidifying component so as to prepare a primary emulsion, and this primary emulsion s ispersed in a second continuous phase as a second dispersion phase so as to prepare a secondary emulsion. The solidifying component in the secondary emulsion is then solidified, and the first dispersion phase is removed leaving pores so as to form porous particles.

Abstract: A water-absorbent resin is produced by dispersing a solid blowing agent having an average particle diameter within a range of from 1 .mu.m to 100 .mu.m in an aqueous monomer solution containing an unsaturated monomer and a cross-linking agent, and then polymerizing the unsaturated monomer. The water-absorbent resin has excellent water absorption characteristics, such as improved dispersion and absorption rate of aqueous fluid, enhanced water retention capacity and dry touch, lower water-soluble component content, and lower residual monomer content. When a water-absorbent resin composition using the water-absorbent resin is used for, for example, a sanitary material, it is possible to improve the absorption rate and water retention capacity, and prevent leakage of fluid from the sanitary material.

Abstract: An apparatus for deionization of a liquid is disclosed. The apparatus has a number of deionization cells, each cell having two different types of electrodes. The first type of electrode is formed from a high surface area absorptive material ("HSAAM electrode") made from resorcinol, formaldehyde, a carbon reinforcing agent, a catalyst, and reaction products thereof, and is in a carbonized form. This electrode removes ions when an electric current is applied. The second type of electrode, which does not remove ions, is formed from a non-HSAAM material. Each deionization cell has a single HSAAM electrode bordered on either side by a non-HSAAM electrode, and adjacent deionization cells do not share any electrodes of either type. The non-HSAAM electrodes are formed from carbon cloth or carbon felt fixed to one side of a plexiglass sheet, and two such sheets are needed to form a cell.

Abstract: High internal phase emulsions having an internal aqueous phase of greater than 70 percent by volume and an external oil phase comprising a vinyl polymerizable monomer contain a surfactant capable of chemically binding to the polymerizable monomer. Polymeric foams having a high internal phase emulsion stabilizing surfactant chemically bound to the polymeric material and a liquid capacity of from about 70 to 99 percent of its saturated volume can be prepared from such emulsions.

Abstract: A flexible aerogel and process of fabrication. An aerogel solution is mixed with fibers in a mold and allowed to gel. The gel is then processed by supercritical extraction, or by air drying, to produce a flexible aerogel formed to the shape of the mold. The flexible aerogel has excellent thermal and acoustic properties, and can be utilized in numerous applications, such as for energy absorption, insulation (temperature and acoustic), to meet the contours of aircraft shapes, and where space is limited since an inch of aerogel is a 4-5 times better insulator than an inch of fiberglass. The flexible aerogel may be of an inorganic (silica) type or an organic (carbon) type, but containing fibers, such as glass or carbon fibers.

Abstract: The present application relates to a process for the preparation of porous, hydrophilic, highly swellable hydrogels, which comprises freeze-drying hydrophilic, highly swellable hydrogels which have been swollen with water.

Abstract: A process for producing a porous film of polypropylene comprises subjecting (1) an air-impermeable biaxially stretched film of polypropylene resin comprised predominantly of polypropylene having a crystallinity of at least 40% or (2) an air-impermeable inflation film of polypropylene resin comprised predominantly of polypropylene having a crystallinity of at least 46.5%, in the substantial absence of a plasticizer or a solvent, to a thermal treatment in the presence of a first liquid substantially incapable of dissolving the film while fixing the film in two orthogonal directions for making the film porous.

Abstract: A process for obtaining an aerogel from a polymeric material that is in the form a sol-gel in an organic solvent, by exchanging the organic solvent for a fluid having a critical temperature below a temperature of polymer decomposition, and supercritically drying the fluid/sol-gel. The process is carried out in a semi-continuous mode that includes the steps of contacting the initial sol-gel with a stream of the fluid at different pressures and temperatures through n+1 pressure vessels A.sub.0 to A.sub.n that each have an inlet for fluid VI.sub.i and an outlet for effluent VO.sub.i wherein the n+1 pressure vessels are operated dependently on each other through a joint fluid supply system and a joint effluent treatment system so that the respective product in each of the pressure vessels A.sub.0 to A.sub.n is submitted to the fluid in successive steps with pressure and temperature following a curve that never cuts the vaporization curve in the pressure-temperature diagram of FIG. 1.

Abstract: A microporous shaped article is provided. The article comprises ethylene-vinyl alcohol copolymer which has an internal structure of a multiplicity of spaced, randomly dispersed, non-uniform shaped particles of ethylene-vinyl alcohol copolymer.

Abstract: The present invention relates to highly asymmetric polymer membranes for ultrafiltration (UF), and to a simplified method of their manufacture. Disclosed herein are UF membranes with a high degree of asymmetry between the size of pores at the skin face of the membrane and the size of pores at the opposite face of the membrane. Asymmetry ratios of these membranes range from about 20 to about 1000. The porous support layer between the skin face and the opposite face is reticular and is substantially free of macrovoids. These membranes thus have higher flow rates than prior UF membranes. The membranes are cast from polymer dope mixes that are either homogeneous solutions or stable colloidal dispersions.

Abstract: Disclosed is a process for preparing an absorbent foam. The process generally comprises forming a solution of a polymer in a solvent, freezing the solution at a relatively slow cooling rate to a temperature below the freezing point of the solvent, removing the solvent from the frozen solution, and recovering the polymer to form a water-swellable, water-insoluble polymeric foam. The process has been found to enable one to prepare an absorbent foam that exhibits desirable softness and flexibility properties yet is highly absorbent. Such an absorbent foam may be used in a disposable absorbent product intended for the absorption of fluids such as body fluids.

Abstract: Very thin microporous material comprises a matrix of substantially linear polyolefin, finely divided substantially water-insoluble filler particles distributed throughout the matrix, and a network of interconnecting pores communicating substantially throughout said microporous material. The very thin microporous material can be produced by the blown film process. The material is used as a separator in a battery.

Abstract: This pertains to the general field of gels, foams, and aerogels, particularly, to low density open cell organic foams and low density open cell carbon foams, and methods for preparing them. These low density open cell organic foams are derived from organic gels which may be prepared from hydroxylated benzenes (such as phenol, catechol, resorcinol, hydroquinone, and phloroglucinol) and aldehydes (such as formaldehyde and furfural) using lower than conventional catalyst concentrations (e.g, an R/C value of greater than about 1000, yielding an initial room temperature pH typically lower than about 6.0). These organic foams are characterized by relatively large particle and pore sizes, high porosity, and high surface area. Low density open cell carbon foams derived from such organic foams are also shown, as are methods for preparing same. These carbon foams are also characterized by relatively large particle and pore sizes, high porosity, high surface area, and high electrical capacitance.

Abstract: This invention relates to porous polyfluoroethylene (PTFE), shaped articles prepared therefrom, and to methods of preparing said articles.

Abstract: A microporous membrane and method of manufacture is presented utilizing irradiation and thermal induction phase separation techniques. During manufacture, microsphereulites are created by irradiation of curable agents in a casted polyolefin film. The microsphereulites then serve as nucleating agents in a thermally-induced phase separation step, providing a microporous membrane with improved flow and mechanical properties.

Abstract: There is provided a cord of twisted polybenzazole fibers, which has a tenacity of 35 g/d or higher and an elastic modulus of 800 g/d or higher. The cord has not only remarkably improved fatigue resistance but also excellent mechanical characteristics at a high level that has not been achieved so far. Therefore, it can attain the weight reduction of composite materials, particularly in the field of reinforced rubber materials, and can also make a great contribution to the energy saving.

Abstract: Polymers are made from 1,3,7-octatriene or like conjugated polyenes and a crosslinking agent having at least 2 activated double bonds such as ethylene glycol dimethacrylate. These polymers can be used to make absorbent foams that are useful in absorbent articles such as diapers, as well as latexes that are useful as binders and adhesives.

Abstract: Fabricated articles of fluoropolymer are foamed by heating the articles to a deformable state, pressurizing the heated article with supercritical CO.sub.2, depressurizing the pressurized heated article while still in the foamable state, whereby said CO.sub.2 foams said article, and cooling the resultant foamed article.

Abstract: Stable high internal phase water-in-oil emulsions containing polymerizable vinyl monomers, crosslinking monomers and initiators are obtained useful in producing low density porous crosslinked polymeric materials by using a surfactant system containing (a) one or more sorbitan fatty acid esters or saccharide fatty acid esters or mixtures thereof and (b) one or more quaternary salts having one or more greater than or equal to 8 carbon atom hydrocarbon groups. A water-in-oil emulsion can be formed with lower surfactant concentration than sorbitan fatty acid ester alone and improved surfactant performance at elevated temperatures is obtained. Sludge formation otherwise observed with the use of sorbitan fatty acid ester surfactants is also reduced or eliminated.

Abstract: A method of producing open porous spherical particles by polymerizing monovinyl monomers and divinyl monomers and/or polyvinyl monomers (cross-linkers) in an emulsion with the aid of an initiator. The method is characterized by the steps of (i) preparing a w/o/w emulsion which comprises an aqueous phase having emulsified therein droplets which contain a water-in-oil emulsion, wherein the oil phase in the droplets includes vinyl monomers and an emulsifier which provides an inverse emulsion and the droplets have a diameter smaller than 2,000 .mu.m, and wherein the total amount of water is between 75-99% (w/w); and (ii) thereafter initiating polymerization and isolating the particles, optionally after sieving, from the reaction mixture after the polymerization process. A population of open spherical porous polymer particles which have a diameter within the range of 50 .mu.m-2,000 .mu.

Abstract: A superabsorbent foam material is made by a water-in-oil high internal phase emulsion polymerization comprising the steps of (a) dissolving an organic solvent-soluble surfactant in a water-insoluble monomer to form an organic phase; (b) blending the-organic phase with an aqueous phase using high shear mixing to form an emulsion, said aqueous phase comprising a water-soluble polymer, a cross-linking agent, and water; (c) polymerizing the water-insoluble monomer in the organic phase; (d) cross-linking the water-soluble polymer in the aqueous phase; and (e) final curing and drying the resulting foam.

Abstract: Foams capable of absorbing blood and blood-based fluids, especially menses. These absorbent foams have high capillary absorption pressures required of absorbents used in catamenial products, yet have sufficient openness to allow free movement of the insoluble components in blood-based fluids such as menses. These absorbent foams are made by polymerizing high internal phase emulsions (HIPEs) where the volume to weight ratio of the water phase to the oil phase is in the range of from about 20:1 to about 125:1. These foams are particularly useful as absorbent members for catamenial pads.

Abstract: Highly asymmetric polyethersulfone membranes prepared from a stable, clear, homogeneous solution or stable colloidal dispersion of polyethersulfone are described. The membranes have a porous skin possessing a high density of skin pores with an average diameter of from about 0.001 micron to about 20 microns. In addition, the membrane has a porous support with an asymmetric region of gradually increasing pore diameters so that the opposite face of the membrane has an average pore diameter that is from about 50 to about 10,000 times the diameter of the skin pores.

Abstract: The present invention relates to vinyl chloride copolymers, in the latex form, the particles of which are composed of a core, of an outer layer and optionally of an intermediate layer. It also relates to the process for the manufacture of this latex by seeded miscosuspension polymerization and to its applications in paints and plastisols.

Abstract: The present invention relates to a HIPE-derived heterogeneous polymeric foam structure of interconnected open-cells, wherein the foam structure has at least two distinct regions. Such heterogeneous foams have various applications, such as energy and fluid absorption, insulation, and filtration.The invention further relates to a heterogeneous absorbent polymeric foam that, upon contact with aqueous fluids (in particular body fluids such as urine and blood), can acquire, distribute, and store these fluids.The foams of the invention have at least two distinct regions having different density, polymer composition, surface properties, and/or microcellular morphology.The invention further relates to a process for obtaining the heterogeneous foams by polymerizing a high internal phase water-in-oil emulsion, or HIPE. In one aspect, the process utilizes at least two distinct HIPEs, with each emulsion having a relatively small amount of an oil phase and a relatively greater amount of a water phase.

Abstract: Highly asymmetric polyethersulfone membranes prepared from a stable, clear, homogeneous solution or stable colloidal dispersion of polyethersulfone are described. The membranes have a porous skin possessing a high density of skin pores with an average diameter of from about 0.001 micron to about 20 microns. In addition, the membrane has a porous support with an asymmetric region of gradually increasing pore diameters so that the opposite face of the membrane has an average pore diameter that is from about 50 to about 10,000 times the diameter of the skin pores.

Abstract: The present invention relates to porous crosslinked polymeric microbeads having cavities joined by interconnecting pores wherein at least some of the cavities at the interior of each microbead communicate with the surface of the microbead. The present invention also relates to a process for producing a porous, crosslinked polymeric microbead as well as the product of this process. This process involves combining an oil phase with an aqueous discontinuous phase to form an emulsion, adding the emulsion to an aqueous suspension medium to form an oil-in-water suspension of dispersed emulsion droplets, and polymerizing the emulsion droplets to form microbeads. At least 10% of the microbeads produced in accordance with the present invention are substantially spherical or substantially ellipsoidal or a combination of the two.

Abstract: Polymers are made from 1,3,7-octatriene or like conjugated polyenes and a crosslinking agent having at least 2 activated double bonds such as ethylene glycol dimethacrylate. These polymers can be used to make absorbent foams that are useful in absorbent articles such as diapers, as well as latexes that are useful as binders and adhesives.

Abstract: Process of mixing a fugitive plasticizer, e.g., ethylene carbonate, with moist particulate polyacrylonitrile then removing the water enabling adjustment of the melt viscosity for extrusion of the polyacrylonitrile into film, fiber, pellets and shaped articles. Stretching and heating the extruded polyacrylonitrile film or fiber causes the fugitive plasticizer to exude and vaporize from the film or fiber, carrying with it any remaining acrylonitrile monomer. The resulting film or fiber exhibits substantially increased molecular weight, thus enhancing the tensile strength and barrier properties of the polyacrylonitrile product. The process also produces polyacrylonitrile foam products. A novel cross-linking agent for polyacrylonitrile, divinyloxybutane, is disclosed. Thermostabilizing agents for polyacrylonitrile, N-maleimides and stilbene derivatives, are also disclosed.

Abstract: Porous, absorbent macrostructures that comprise flexible interparticle bonded aggregates and are useful in absorbent articles such as diapers, adult incontinence pads, and sanitary napkins are disclosed. These porous macrostructures are treated with an effective amount of a latex to coat at least a portion of the particles comprising the bonded aggregate so as to impart increased flexibility to the macrostruture. This latex is capable of being sintered at a temperature of about 25.degree. C. or lower, is at least somewhat hydrophilic when sintered, and has a Tg of about 25.degree. C. or lower when sintered.

Abstract: A method of preparing superabsorbent polymer as crosslinked polyaspartate salt by reacting polysuccinimide dissolved in organic solvent with crosslinker and reacting the polysuccinimide in situ with neat or a solution of alkali metal hydroxide to form the crosslinked salt.

Abstract: A process for forming biocompatible porous matrices of bioabsorbable materials comprising:a) providing a bioabsorbable polymer;b) dissolving the bioabsorbable polymer in a volumetric orientation aid to yield a molten solution;c) solidifying the molten solution to yield an orientation matrix comprising first and second phases, the first phase being the bioabsorbable polymer and the second phase being the volumetric orientation aid; andd) removing the volumetric orientation aid while the solution is solid; to yield a biocompatible matrix of bioabsorbable polymer. Also matrices formed by the process and devices made with such matrices.

Abstract: The present invention relates to a HIPE-derived heterogeneous polymeric foam structure of interconnected open-cells, wherein the foam structure has at least two distinct regions. Such heterogeneous foams have various applications, such as energy and fluid absorption, insulation, and filtration.The invention further relates to a heterogeneous absorbent polymeric foam that, upon contact with aqueous fluids (in particular body fluids such as urine and blood), can acquire, distribute, and store these fluids.The foams of the invention have at least two distinct regions having different density, polymer composition, surface properties, and/or microcellular morphology.The invention further relates to a process for obtaining the heterogeneous foams by polymerizing a high internal phase water-in-oil emulsion, or HIPE. In one aspect, the process utilizes at least two distinct HIPEs, with each emulsion having a relatively small amount of an oil phase and a relatively greater amount of a water phase.

Abstract: A method for altering a macroporous cross-linked hydrophobic copolymeric lattice produced by precipitation polymerization in a solvent of at least one monounsaturated ester monomer and at least one polyunsaturated ester monomer soluble therein, in order to render the hydrophobic copolymeric lattice hydrophilic. The method involves saponifying the hydrophobic copolymeric lattice by reacting the surface of the hydrophobic copolymeric lattice with an aqueous alkali. The surface can also be rendered hydrophilic by polymerizing an acrylate monomer onto the lattice in order to form a surface containing carboxylic acid sites. The carboxylic acid sites formed on the surface of the lattice are converted to carboxylate anions.

Abstract: Foam materials based on copolymers of styrene with from 2 to 50 mol % of 1,1-diphenylethene have a high heat distortion resistance.

Abstract: Absorbent foams materials that are capable of acquiring and distributing aqueous fluids, especially discharged body fluids such as urine. These absorbent foams combine relatively high capillary absorption pressures and capacity-per-weight properties that allow them to acquire fluid, with or without the aid of gravity. These absorbent foams also give up this fluid efficiently to higher absorption pressure storage materials, including foam-based absorbent fluid storage components, without collapsing. These absorbent foams are made by polymerizing high internal phase emulsions (HIPEs).

Abstract: Foams capable of absorbing blood and blood-based fluids, especially menses. These absorbent foams have high capillary absorption pressures required of absorbents used in catamenial products, yet have sufficient openness to allow free movement of the insoluble components in blood-based fluids such as menses. These absorbent foams are made by polymerizing high internal phase emulsions (HIPEs) where the volume to weight ratio of the water phase to the oil phase is in the range of from about 20:1 to about 125:1. These foams are particularly useful as absorbent members for catamenial pads.

Abstract: Highly uniform microporous foam suitable for medical applications and methods for preparing these foams. The highly uniform microporous foams are of controlled pore size that may be utilized in a variety of applications. In preparing the foams, an organic crystalline polymer is melted and combined with a selected solid crystalline fugitive compound to produce a substantially isotropic solution. The solution is cooled under controlled conditions, which foster solid--solid phase separation by the simultaneous crystallization of the fugitive compound and the polymer, to produce a foam precursor containing the solidified fugitive compound dispersed through a matrix of the organic polymer. Crystals of fugitive compound are then removed by solvent extraction and/or sublimation, or like process to produce microcellular foams having a continuous, open-cell structure.

Abstract: Disclosed are methods of producing super absorbing polymeric networks of polyaspartates from crosslinked polysuccinimide. In one preferred method aspect, polysuccinimide is first reacted with an organic crosslinking agent, preferably an organic base containing at least two primary amine groups to form crosslinked polysuccinimide. The crosslinked polysuccinimide is then hydrolyzed to a polymeric network of polyaspartate which demonstrates super absorbing capability in water and in saline solution. Alternative method aspects are disclosed in which super absorbing polymeric networks of polyaspartates are produced in a single reaction vessel by sequentially crosslinking polysuccinimide with organic crosslinking agent in an aqueous reaction mixture and then hydrolyzing the reaction product to produce a polymeric network of polyaspartate.

Abstract: The disclosed invention is a crystalline microporous polymer and process for preparing a low density microporous polymer comprising, providing a mixture of a polymer and a polymer solvent, the mixture capable of achieving a supercritical condition; applying pressure, at a temperature sufficient for the mixture to attain a super critical condition; cooling the supercritical solution that results and precipitating a microporous crystalline polymer product.

Abstract: This invention relates to porous polyfluoroethylene (PTFE), shaped articles prepared therefrom, and to methods of preparing said articles.

Abstract: Biaxially oriented films from high molecular weight polyethylene are characterized by a gas permeable structure formed from random-arranged microfibrils. The films have coefficients of static friction and kinetic friction of not more than 1.0. The biaxially oriented films are further characterized by service smoothness as well as tensile (tangent) modulus and tensile strength. The films may be used for lamination, filter, or for packaging for moisture absorbers. The biaxially oriented films may be obtained by extracting a hydrocarbon plasticizer from a sheet formed from the high molecular weight polyethylene and a hydrocarbon plasticizer, stretching the resulting sheet to obtain an oriented film having a specific surface area of at least 70 m.sup.2 /g and a fibril structure, and heating the oriented film under a standard length constraint to reduce the oriented film in specific area by at least 20 m.sup.2 /g.

Abstract: A syntactic foam-core material and method for its production are disclosed wherein glass microspheres and chopped fiberglass are dispersed within a slurry comprised of a suitable resin such as an epoxy and a suitable solvent such as methyl ethyl ketone. Under carefully controlled vacuum and rate of addition conditions, the microspheres and chopped fiberglass are added to the slurry to form a light weight syntactic foam-core material. The material may either be stored under cold conditions for use at a later time as a B-stage material or it may be shaped and/or molded to conform to a desired configuration which, for example, may correspond with a desired component part. After curing, the material may be machined to final dimensions. The material may be characterized as a tightly packed network of resin-coated microspheres spaced by controlled, yet random voids comprising at least 20%, and more usually, between 23 and 25% by volume, of the fully-cured material.

Abstract: This invention relates to a process for forming a single-layer, durably wettable polymeric web having a plurality of apertures. This process comprises melting a mixture of at least one thermoplastic polymer and at least one migratable surfict and extruding the mixture to form a single-layer, substantially continuous polymeric film. The film is then apertured using high pressure fluid flows. Aperture formation is conducted when the single layer polymeric film has a contact angle of at least about 30.degree., to minimize wash-off of the surfactant impregnated in the polymer web. The invention also relates to durably-wettable apertured webs.

Abstract: Fabricated articles of fluoropolymer are foamed by heating the articles to a deformable state, pressurizing the heated article with supercritical CO.sub.2, depressurizing the pressurized heated article while still in the foamable state, whereby said CO.sub.2 foams said article, and cooling the resultant foamed article.

Abstract: An improvement in a continuous process for making high internal phase emulsions that are typically polymerized to provide microporous, open-celled polymeric foam materials capable of absorbing aqueous fluids, especially aqueous body fluids such as urine. The improvement involves recirculating a portion (about 50% or less) of the emulsion withdrawn from the dynamic mixing zone of this continuous process. This increases the uniformity of the emulsion ultimately obtained from this continuous process in terms of having the water droplets homogeneously dispersed in the oil phase. This also improves the stability of the HIPE and expands the temperature range for pouring and curing this HIPE during subsequent emulsion polymerization. The improvement also eliminates the need for a static mixer outside the dynamic mixing zone, and allows for processing where relatively low pressure drops are required across the mixing zone.

Abstract: The present invention relates to a HIPE-derived heterogeneous polymeric foam structure of interconnected open-cells, wherein the foam structure has at least two distinct regions. Such heterogeneous foams have various applications, such as energy and fluid absorption, insulation, and filtration.The invention further relates to a heterogeneous absorbent polymeric foam that, upon contact with aqueous fluids (in particular body fluids such as urine and blood), can acquire, distribute, and store these fluids.The foams of the invention have at least two distinct regions having different density, polymer composition, surface properties, and/or microcellular morphology.The invention further relates to a process for obtaining the heterogeneous foams by polymerizing a high internal phase water-in-oil emulsion, or HIPE. In one aspect, the process utilizes at least two distinct HIPEs, with each emulsion having a relatively small amount of an oil phase and a relatively greater amount of a water phase.

Abstract: A blood-absorbable resin composition characterized by having a blood area ratio relative to sheep blood of not less than 30% at a basis weight of 150 g/m.sup.2 and an absorbent article containing the composition. The blood-absorbable resin composition of this invention possesses an excellent ability to absorb blood and, therefore, is highly useful for sanitary napkins, tampons, medical blood-absorbable articles, trauma protectors, trauma healing materials, and reagents for treating liquid refuses from surgical operations.