Abstract: A process produces microporous powders or shaped articles, in particular membranes in the form of flat films, tubular films or hollow fibers, which may be used for controlled release of an active compound, for dialysis, gas separation, ultrafiltration or microfiltration, from polyvinylidene fluoride and/or polyphenylene sulfide and/or polysulfone and/or polyacrylonitrile and/or ethylene/vinyl alcohol copolymer and/or ethylene/chlorotrifluoroethylene copolymer and/or polyethersulfone and/or polyether-imide and/or polymethyl methacrylate and/or polycarbonate and/or cellulose triacetate. The process utilizes phase separation by means of thermally induced triggering or triggering induced by a non-solvent of a solution of the polymer in a mixture containing .epsilon.-caprolactam as the essential dissolving constituent. The solution may be formed before the phase separation is triggered.

Abstract: A method of manufacturing a porous membrane by dissolving vinylidene fluoride polymer in a good solvent such as acetone and then causing solidification of the resultant solution in a non-solvent. The dissolution of the vinylidene fluoride polymer in the solvent is done in a predetermined pressure condition, namely 0.1 kg/cm.sup.2, preferably in a range of 0.5 to 5.0 kg/cm.sup.2.

Abstract: A substrate comprises a porous polymeric material having a porosity of at least 75% and comprising pores having a diameter within the range 1 to 100 .mu.m and being interconnected by a plurality of holes, and a gel or material adapted in use to form a gel which gel or pre-gel materials is contained and retained within the pores of the polymeric material and is adapted in use to interact with a reactive species and can be made by depositing and retaining the gel or a material adapted in use to form the gel within the pores of the porous polymeric material. The high porosity of the porous polymeric material in combination with the retention of the gel within the pores permit high loading capacities, particularly in the area of peptide synthesis to be achieved. The substrate can be employed in chemical synthesis, chromatography techniques, ion exchange and separation techniques.

Abstract: Polyimide ultrafiltration membranes made using a single solvent and containing a pore forming agent have been produced and have been found to be useful for recovering dewaxing aid used in dewaxing process.

Abstract: The invention is a composition useful for the preparation of POWADIR membranes of a bisphenol-based polycarbonate wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated, wherein the halogen is Cl or Br, the composition comprising (i) a bisphenol-based polycarbonate wherein at least 25 percent by weight of the bisphenol moieties are tetrahalogenated, wherein the halogen is Cl or Br, (ii) a solvent for such polycarbonate, and (iii) a non-solvent for such polycarbonate. The composition is useful for extruding membranes wherein the membranes formed are POWADIR membranes with a discriminating region capable of separating oxygen from nitrogen.The composition of this invention allows the formation of membranes with excellent physical properties, good separation factors for oxygen and nitrogen, with excellent fluxes.

Abstract: The composition comprises polyolefins, fillers and a plasticizer. It contains 0.2 to 20 wt. % etoxysiloxane, 5 to 60 wt. % polyolefin, 10 to 60 wt. % white black filler, and 10 to 75 wt. % polyethyleneglycol, petroleum oil or dioctylphtalate. The polyolefin can be high-density polyethylene with a melt index at a standard charging up to 6, superhigh-molecular polyethylene, polypropylene, or a mixture of polypropylene and polyethylene, or of high-density polyethylene and super-high-molecular polyethylene at as ratio of 0 to 100 wt. parts high-density polyethylene for every 100 wt. parts super-high-molecular polyethylene. The composition is prepared by treating the filler with etoxysiloxane at room temperature, then adding the polyolefin and the plasticizer to form a mixture, and then homogenizing the mixture in a cold state or with heating. With this composition are prepared microporous separators having an average pore size of below 0.05.mu., and having high physicomechanical properties.

Abstract: An active agent delivery device comprises (a) microporous material comprising a matrix consisting essentially of linear ultrahigh molecular weight polyolefin, a large proportion of finely divided water-insoluble filler of which at least about 50 percent by weight is siliceous, and interconnecting pores; and (b) a releasable active agent or precursor thereof associated with at least a portion of the filler.

Abstract: High boiling point polar organic solvent are useful solvents for poly(etheretherketone)-type polymers (PEEK). Solutions of PEEK may be used to form PEEK articles such as film, microporous sheet membrane, fiber and microporous hollow fibers. The microporous PEEK is useful as an ultrafiltration membrane and as a substrate for the formation of reverse osmosis membranes. A method of making PEEK articles including microporous sheet membranes is disclosed. A method of making PEEK fibers including microporous hollow membrane fibers is disclosed.

Abstract: The semipermeable membrane contains a polyarylate resin and a polysulfone resin as a major membrane material and has a fibrilliform structure with a high mechanical strength and has a water permeability of 1,500 ml/m.sup.2.hr.mmHg or lower as well as an inhibitory rate against bovine serum albumin of 80% or higher and against cytochrome C of 40% or lower. The membrane is prepared by discharging a stock solution containing the polyarylate resin and the polysulfone resin in the total amount of 10% to 25% by weight and a core solution of an organic solvent containing water in the amount of 25% to 80% by volume into a coagulating solution.

Abstract: A microporous particulate-filled thermoplastic polymeric article is provided. The article can be in the form of a film, a fiber, or a tube. The article has a thermoplastic polymeric structure having a plurality of interconnected passageways to provide a network of communicating pores. The microporous structure contains discrete submicron or low micron-sized particulate filler, the particulate filler being substantially non-agglomerated.

Abstract: Highly crosslinked polymer particles, which may be porous, consisting essentially of a non-hydrophilic polymer can be produced by adding a polymerizable monomer mixture comprising at least 20% by weight of at least one non-hydrophilic, crosslinking polyvinyl monomer to an aqueous dispersion containing a non-crosslinked, low molecular weight polymer particles having a weight average molecular weight of 500-10,000 as a dispersoid, with a non-reactive solvent in a proportion of not more than 1 part by weight per part by weight of the polymerizable monomer mixture, the proportion of the polymerizable monomer mixture plus the non-reactive solvent to the non-crosslinked, low molecular weight polymer particles being 4 to 20 parts by weight per part by weight of the non-crosslinked, low molecular weight polymer particles, and then subjecting the polymerizable monomer mixture to radical emulsion polymerization with stirring.

Abstract: A precipitation polymerization process for producing a macroporous cross-linked copolymeric lattice, capable of adsorbing hydrophilic and lipophilic fluids, in which process there is copolymerized at least one monounsaturated monomer and at least one polyunsaturated monomer in the presence of an organic liquid which is a solvent for the monomers but not for the copolymer, initiating the copolymerization of the monomers by means of a free radical generating catalytic compound, precipitating a copolymer in the solvent in the form of a powder, and forming a dry powder by removing the solvent from the precipitated copolymeric powder. One monomer is a hydrophilic compound and the other monomer is a lipophilic compound.

Abstract: Isotropic porous polymer beads having controllable surface porosity and large pore diameters from about 0.002 to about 5 microns are produced from solutions of an acrylonitrile polymer or a copolymer by a thermally-induced phase separation process including intensively shearing the polymer solution into small droplets. The use of mixed solvent non-solvent combinations as solvents for the polymers, and preferably reducing the polymer content in solution to below 10 percent produces high pore content, substantially spherical beads having a morphology ideally suited to the chromatography of large molecules, such as proteins, and for enzyme-binding.

Abstract: A process for producing a composite membrance in which a sulphonated polymer is appled to the surface of a porous substrate, treating the polymer, in situ, on the substrate with cations of a polyvalent metal and converting the treated coating into a water insoluble layer on the support. The polyvalent metal may preferably by aluminum or chromium.

Abstract: A polyamide powder consisting essentially of elementary porous particles having a "gypsum rose" structure and a process for preparing a polyamide powder comprising polymerizing by anionic polymerization lactam in a solvent medium in the presence of a catalyst, an activator, and at least one amide; one of which is N,N'-alkylene bisamide; said polymerization being initiated with said lactam and said amide used in an amount such that the solvent is in the supersaturated state at the polymerization initiation temperature.

Abstract: A process by which polyester resin having extremely high molecular weight can be prepared utilizing a very rapid solid state polymerization process comprises: (1) dissolving a polyester prepolymer in a suitable organic solvent; (2) recovering the polyester prepolymer from the organic solvent to produce a porous, fibrous mass of the polyester prepolymer; and (3) solid state polymerizing the porous, fibrous mass at an elevated temperature to produce the ultra-high molecular weight polyester resin.

Abstract: A process for producing hollow polymer latex particles, which comprises(1) adding a base to a carboxyl-containing polymer latex obtained by emulsion polymerization of a monomeric mixture composed of at least 0.1% by weight of an ethylenically unsaturated carboxylic acid and another ethylenically unsaturated monomer copolymerization with the carboxylic acid to adjust the pH of the polymer latex to at least 7 and swell the polymer latex particles, and(2) adding an acid to the polymer latex formed in (1) to adjust the pH of the latex to not more than 7.

Abstract: Capsule-shaped polymer particles and a process for the production thereof are described. In one embodiment of the process, a polymerizable monomer component containing a cross-linkable monomer and a hydrophilic monomer, and an oily substance are finely dispersed in water to prepare an oil-in-water emulsion and then the polymerizable monomer component is polymerized, whereupon capsule-shaped polymer particles containing the oily substance as a core material are obtained. Upon removal of the oily substance in the particles, there are obtained capsule-shaped hollow polymer particles. These capsule-shaped polymer particles are excellent in such properties as mechanical strength and heat resistance, and thus can find many applications.

Abstract: Microporous poly (tetrafluoroethylene-co-perfluoro (alkyl vinyl ether)) (PFA) or poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) membrane or hollow fibers are formed from a melt blend of 10 to 35 weight percent of PFA or FEP and a chlorotrifluoroethylene oligomer solvent. The melt blend is shaped and cooled to effect phase separation of the PFA or FEP from the blend. The solvent is removed from the PFA or FEP by extraction and the porous PFA or FEP is dried under restraint to prevent shrinkage.

Abstract: Microporous poly (tetrafluoroethylene-co-perfluoro (alkyl vinyl ether)) (PFA) or poly(tetrafluoroethylene-co-hexafluoropropylene) (FEP) membrane or hollow fibers are formed from a melt blend of 10 to 35 weight percent of PFA or FEP and a chlorotrifluoroethylene oligomer solvent. The melt blend is shaped and cooled to effect phase separation of the PFA or FEP from the blend. The solvent is removed from the PFA or FEP by extraction and the porous PFA or FEP is dried under restraint to prevent shrinkage.

Abstract: Aesthetically attractive, free standing dispensers for the controlled release of volatile liquid materials such as perfumes and fragrances into the atmosphere consist essentially of composite hydrogels comprising a continuous phase of a solubilized polyvinyl alcohol, a dispersed phase comprising a polyelectrolyte and an aqueous solution of the volatile liquid that is distributed between said continuous and dispersed phases. The exterior surfaces of the dispenser remain dry to the touch throughout its useful life.

Abstract: Aesthetically attractive, free standing dispensers for the controlled release of volatile liquid materials such as perfumes and fragrances into the atmosphere are prepared by (1) forming a first solution by heating a mixture comprising polyvinyl alcohol and water and/or dimethyl sulfoxide under atmospheric pressure, (2) adding a second solution comprising a volatile liquid material and a monohydric alcohol in a solvent that is miscible with the first solution under conditions that avoid precipitation of polyvinyl alcohol, and then (3) cooling the resultant solution to below room temperature to form a gel in the shape of the final dispenser. The exterior surfaces of the dispenser remainds dry to the touch throughout its useful life.

Abstract: Aesthetically attractive, free standing dispensers for the controlled release of volatile liquid materials such as perfumes and fragrances into the atmosphere consist essentially of composite hydrogels comprising a continuous phase of a solubilized polyvinyl alcohol, a dispersed phase comprising a polyelectrolyte and an aqueous solution of the volatile liquid that is distributed between said continuous and dispersed phases. The exterior surfaces of the dispenser remain dry to the touch throughout its useful life.

Abstract: Foamed microbeads with a shell and an encased core are characterized in that the shell is a reaction product of an NCO-containing carbodiimide and a polyamine, and the core is at least partly filled with a polymeric carbodiimide or its reaction product with a polyamine, and in that the foamed microbeads are self-supporting and can be laden with hydrophilic and if appropriate hydrophobic liquids.

Abstract: Multi-stage polymer particles containing one or more void space(s) therein are produced by sequential emulsion polymerization of an essentially low-acid earlier polymer stage, encapsulation of said low-acid polymer stage with at least a final polymer stage, contacting said polymer particles with a non-polymeric carboxylic acid to permit the acid to be absorbed into said low-acid polymer stage and swelling the polymer particles by contacting the particles with an aqueous base. The low-acid polymer stage is formed by emulsion polymerizing a monomer system comprising ethylenically unsaturated monomer(s) and containing less than 5% by weight of monomer(s) containing acid functionality. The low-acid polymer stage is subsequently encapsulated by one or more polymer stages by emulsion polymerizing ethylenically unsaturated monomer(s) in the presence of the low-acid polymer stage. The final stage has a glass transition temperature (Tg) of about 50.degree. C.

Abstract: The polycondensation of resorcinol with formaldehyde under alkaline conditions results in the formation of surface functionalized polymer "clusters". The covalent crosslinking of these "clusters" produces gels which when processed under supercritical conditions, produce low density, organic aerogels (density .ltoreq.100 mg/cc; cell size .ltoreq.0.1 microns). The aerogels are transparent, dark red in color and consist of interconnected colloidal-like particles with diameters of about 100 .ANG.. These aerogels may be further carbonized to form low density carbon foams with cell size of about 0.1 micron.

Abstract: Microscopic particles containing a continuous network of pores open to the particle surface are manufactured of a spongy material. The particles are useful as controlled-release delivery systems for active substances intended for a wide range of uses including topical applications. The spongy character of the particles enhances their usefulness in applications where high pressure or high temperature are encountered, and where exceptional smoothness of feel is required.

Abstract: A sulphonated aromatic polymer containing repeating units (Ar-Y) (where Y is SO.sub.2 and/or CO), where at least half of groups Ar contain a group SO.sub.3 M and M is l/m of a polyvalent metal cation in at least 80% of such groups SO.sub.3 M, and where m is the valency of the ion. The polyvalent cation compound is formed by heating the corresponding sulphonic acid or monovalent cation compound with a salt of a polyvalent metal. The polymer is useful as a membrane and the polyvalent metal salt addition and/or the heat treatment may be applied to polymer in membrane form.

Abstract: Swollen core/sheath polymeric particles are disclosed having one or more voids in the core formed by reaction with a base such as sodium hydroxide. The sheath contains styrene or similar monomer polymerized in an amount greater than 25 mole percent and the polymer is free of acid groups. The core contains acid groups. Swelling is effected at an elevated temperature and in the absence of an organic solvent.The swollen particles on drying in a paint or other composition have air in the voids and act then as opacifying agents.

Abstract: Porous cross-linked polyvinyl alcohol particles which is used for a chromatographic medium is prepared by:dispersing an aqueous solution of a mixture of polyvinyl alcohol and a salt in an organic solvent;allowing a gel to form spontaneously from the dispersion; andreacting the gel with a cross-linking agent.

Abstract: A process of forming hollow microspheres containing carbon or a polymer which is a carbon precursor. The process comprises forming a solution in a liquid solvent of a polymer having the following properties (a) a molecular weight of at least 10,000 and a long chain structure; (b) an ability to be coagulated by or precipitated from the solution by a non-solvent for the polymer; (c) an ability to form a continuous stretchable film when coagulated or precipitated from solution; (d) a chemical structure which is infusible or capable of being rendered infusible, and (e) a high carbon yield of at least 30% by weight upon being carbonized in a non-reactive atmosphere. An insoluble particulate blowing agent is incorporated into the solution and the solution is then divided into droplets and the droplets are introduced into a liquid bath containing a suitable non-solvent for the polymer.

Abstract: A method of producing a plastic sheet with a porous surface layer suitable for use as, for example, a recording medium on which characters and images are printed by ink jet or thermal-transfer printing method. The method comprises preparing a solution by dissolving two or more kinds of plastics having low levels of miscibility to each other in a solvent, applying said solution to a substrate, passing said substrate with said solution applied thereto through a liquid which dissolves said solvent but does not dissolve said plastics thereby solidifying said plastics, and drying said substrate with the solidified plastic layer. Preferably, two or more kinds of plastics having low levels of miscibility to each other include mainly a material A which is vinyl chloride or its compolymer and a material B which is acrylonitrile or its copolymer.

Abstract: This invention discloses novel membranes comprised of a blend of polyarylate and polybenzimidazole polymers. A membrane prepared from the blend of polybenzimidazole and polyarylate polymers exhibits enhanced properties over membranes prepared solely from either a polyarylate or a polybenzimidazole polymer. The addition of the polyarylate to the polybenzimidazole membrane allows the composition to be more thermally processable and less susceptible to moisture. The presence of the polybenzimidazole renders the polyarylate less reactive to solvents and increases its thermal stability. In addition, it has been surprisingly found that membranes prepared from the polybenzimidazole polyarylate blends show high regeneration capacity while retaining good flux ranges. The membranes prepared by this process exhibit good separation characteristics and provide an improved membrane with enhanced qualities over prior art membranes.

Abstract: The present invention provides a process for manufacturing a porous polymer containing many voids in its interior, which has a small apparent specific gravity and is superior in terms of water absorbing properties, permeability and elasticity. The process comprises (1) forming O/W emulsion by using a water soluble surfactant wherein an inner phase of the O/W emulsion is a hydrophobic phase and an outer phase thereof is a water phase containing at least one water-soluble polymerizable monomer; (2) adding said O/W emulsion to a hydrophobic dispersing medium containing an oil-soluble surfactant to form O/W/O emulsion; and (3) polymerizing the monomer.

Abstract: Precursor microporous material comprising a matrix consisting essentially of linear ultrahigh molecular weight polyolefin, a large proportion of finely divided water-insoluble siliceous filler, and interconnecting pores is stretched to increase the porosity and provide regions of stretch-induced molecularly oriented polymer in the matrix.

Abstract: A polyamide powder consisting essentially of elementary porous particles having a "gypsum rose" structure and a process for preparing a polyamide powder comprising polymerizing by anionic polymerization lactam in a solvent medium in the presence of a catalyst, an activator, and at least one amide; one of which is N,N'-alkylene bisamide; said polymerization being initiated with said lactam and said amide used in an amount such that the solvent is in the supersaturated state at the polymerization initiation temperature.

Abstract: A method of producing a porous material having open pores comprises the steps of preparing an emulsion slurry by vigorously agitating a mixture comprising (i) a glycidyl type epoxy resin, (ii) a first hardener selected from the group consisting of modified polyamine hardeners each being prepared by modifying a polyamine hardener with a modifier, amine hardeners and mixtures thereof, (iii) a second hardener selected from the group consisting of polyamide hardeners, (iv) a filler and (v) water, casting said slurry in a water-impermeable mold, and hardening said slurry while it contains water. A large size molded product having a complicated contour and having open pores whose average pore diameter ranges from 0.2 to 10 microns can be produced with high dimensional accuracy.

Abstract: Disclosed herein are microporous polybenzimidazole articles prepared by the addition of a leachable additive to a polybenzimidazole polymer solution or dope and the subsequent leaching of the additive from the polybenzimidazole article. The microporous polybenzimidazole article may be formed into filaments or films. The micropores of the microporous polybenzimidazole article may be filled with an absorbent resin which will act to absorb chemicals or other harmful products. The microporous polybenzimidazole article with absorbent material may be formed into clothing which is highly resistant to both chemicals and heat.

Abstract: Vesiculated granules of cross-linked carboxylated polyester resin prepared by the free radical polymerization of a dispersion of an ethylenically unsaturated monomer, a carboxylated unsaturated polyester resin having an acid value of from 5-50 mg KOH/g and an alkyl acryloyl derivative. Aqueous compositions comprising the granules are used in conjunction with fibrous cellulosic or non-cellulosic materials for the preparation of paper containing the vesiculated polymeric granules dispersed therein. The paper has improved optical opacity.

Abstract: Solutions of sulphonated polyaryletherketones in a solvent mixture of at least three liquids or low melting solids which are non-solvents or poor solvents for the polymer, can be used to produce asymmetric semi-permeable membranes. The polymer may be a polymer of--Ph.sup.1 --O--Ph.sup.2 --O--Ph.sup.1 --CO--and optionally--Ph.sup.1 --O--Ph.sup.1 --CO--and--Ph.sup.1 --O--Ph.sup.1 --O--Ph.sup.1 13 COp13 p0wherein Ph.sup.1 and Ph.sup.2 are respectively unsulphonated and sulphonated phenylene residues. The components of the solvent mixture have specified solubility parameters. A suitable solvent mixture is one formed from water, 1,4-dioxane and acetonitrile.

Abstract: Vesiculated granules of cross-linked carboxylated polyester resin prepared by the free radical polymerization of a dispersion of an ethylenically unsaturated monomer, a carboxylated unsaturated polyester resin having an acid value of from 5-50 mg KOH/g and an alkyl acryloyl derivative. Aqueous compositions comprising the granules are used in conjunction with fibrous cellulosic or non-cellulosic materials for the preparation of paper containing the vesiculated polymeric granules dispersed therein. The paper has improved optical opacity.

Abstract: A process for preparing assymetric polyvinylidene fluoride microporous membranes using novel pore forming agents of an ammonium salt which is a non-solvent for the polymeric casting solution; such agents for example being ammonium hydroxide, ammonium chloride and the like.

Abstract: An aqueous slurry of gypsum plaster is stabilized by an organic, polymeric, hydrophilic stabilizer for more than 30 days without setting.Upon activation with a Lewis acid the slurry becomes hydrated. The plaster form or the hydrated form may be employed to impregnate a substrate to form insulating sheeting. The substrate may be fabric, felt, paper, nonwoven, or sponge.Open-cell, foamed gypsum may be used alone or molded to shaped articles such as bricks for a firewall.

Abstract: Foamed microbeads with a shell and an encased core are characterized in that the shell is a reaction product of an NCO-containing carbodiimide and a polyamine, and the core is at least partly filled with a polymeric carbodiimide or its reaction product with a polyamine, and in that the foamed microbeads are self-supporting and can be laden with hydrophilic and if appropriate hydrophobic liquids.

Abstract: A method of producing a porous material having open pores comprises the steps of preparing an emulsion slurry by vigorously agitating a mixture comprising a main ingredient, a polyamide hardener, a filler and water, casting said emulsion slurry in a water-impermeable mold, hardening said slurry while it contains the water. The main ingredient is a bisphenol-type epoxy resin added with one or more reactive diluents each having one or more epoxy rings per molecule and added in an amount of 18 to 50 wt %, based on 100 wt % of said bisphenol-type epoxy resin. A large size molded product having a high wet bending strength and a complicated contour can be produced.

Abstract: This invention discloses a novel elastic cross-linked porous polymer having a porosity in the range 75 to 98% internal phase volume and having interconnected pores, said pores having a mean pore diameter in the range 15 .mu.m to 80 .mu.m, said polymer having an elastic return from 50% compression to 90% of initial thickness of less than 120 seconds, and a process for its production.

Abstract: A microporous membrane suitable for use in microfiltration. The membrane is a hydrophilic skinless sheet, formed of polytetramethylene adipamide, either alone, or in admixture with at least one other polyamide.

Abstract: A process for forming hollow microspheres containing carbon or a polymer which is a carbon precursor. The process comprises forming a solution in a liquid solvent of a polymer having the following properties (a) a molecular weight of at least 10,000 and a long chain structure; (b) an ability to be coagulated by or precipitated from the solution by a non-solvent for the polymer; (c) an ability to form a continuous stretchable film when coagulated or precipitated from solution; (d) a chemical structure which is infusible or capable of being rendered infusible, and (e) a high carbon yield of at least 30% by weight upon being carbonized in a non-reactive atmosphere. An insoluble particulate blowing agent is incorporated into the solution and the solution is then divided into droplets and the droplets are introduced into a liquid bath containing a suitable non-solvent for the polymer.

Abstract: A process for preparing assymetric polyvinylidene fluoride microporous membranes using novel pore forming agents of an ammonium salt which is a non-solvent for the polymeric casting solution; such agents for example being ammonium hydroxide, ammonium chloride and the like.

Abstract: A process for producing a microcellular cast resin product, by casting a water-in-oil emulsion of polymerizable components which will gel and partially polymerize by an exothermic reaction, and placing the partially polymerized casting in a fluid medium maintained at a temperature and pressure such that evaporation of water and monomers is inhibited but sufficient to promote complete polymerization while retaining dispersed water within a microcellular structure. The water content of the emulsion can range from about 1% to about 90% by weight, and the microcellular structure may be either the open cell or the closed cell type.