Abstract: The invention relates to a terpolymer of tetrafluoroethylene (TFE) monomer, polyvinylidene fluoride (PVDF) monomer and hexafluoropropylene (HFP) monomer for forming an ultrafiltration or microfiltration membrane, method of forming said membranes, and to the ultrafiltration or microfiltration membranes themselves. The invention also relates to a method of forming a polymeric ultrafiltration or microfiltration membrane including preparing a leachant resistant membrane dope which incorporates a leachable pore forming agent, casting a membrane from the dope and leaching the pore forming agent from the membrane. The invention also relates to a method of preparing a polymeric ultrafiltration or microfiltration membrane of improved structure including the step of adding a nucleating agent to the membrane dope before casting.

Abstract: A method of producing a hollow fiber membrane includes discharging a polyvinylidene fluoride solution comprising a polyvinylidene fluoride resin and a poor solvent at a temperature above a phase separation temperature into a cooling bath at a temperature below the phase separation temperature to coagulate the polyvinylidene fluoride resin. The hollow fiber membrane comprises a polyvinylidene fluoride resin having spherical structures that have an average diameter in the range of 0.3 to 30 ?m.

Abstract: A grip element having a soft, compressible and deformable outer layer supported by an underlying support structure sufficiently rigid to maintain a receiving channel of the grip element in an open configuration. The support structure facilitates manipulation of the grip element and assembly of the grip element onto a hand-held article without having the outer layer collapse on itself as would occur without the support structure as a result of the soft, deformable nature of the outer layer. The grip element may be formed separately from the hand-held article on which it is to be assembled, and then positioned thereon such that the hand-held article is sold with the grip element pre-assembled thereon. If desired, the grip element may be provided separate from the hand-held article, the outer layer providing a readily compressible and deformable soft cushioning surface and the support structure facilitating insertion of the outer layer over at least a portion of a hand-held article.

Abstract: A method and apparatus for manufacturing a rubber sheet containing short fibers. The method includes the steps of: mixing short fibers in a flowable rubber matrix; forming the flowable rubber matrix with the fibers therein into a cylindrical shape with a circumferential extent; separating a portion of the circumferential extent from the cylindrical shape, and forming the cylindrical shape with the portion separated into a sheet form.

Abstract: A method of manufacturing a hose includes the step of extruding a tube assembly comprising (i) a first inner non-foamed layer, (ii) a first outer non-foamed layer positioned around the first inner non-foamed layer, and (iii) a first foamed layer interposed between the first inner non-foamed layer and the first outer non-foamed layer. The method further includes the step of positioning a textile reinforcement on the tube assembly. Additionally, the method includes the step of extruding a cover assembly over the textile reinforcement, the cover assembly comprising (i) a second inner non-foamed layer, (ii) a second outer non-foamed layer positioned around the second inner non-foamed layer, and (iii) a second foamed layer interposed between the second inner non-foamed layer and the second outer non-foamed layer.

Abstract: A method and apparatus are disclosed for slip-form casting a concrete product, the product being made from at least two different grades of concrete so that the concrete mix grade can be changed in an uninterrupted fashion during casting at a desired point along the length of the casting bed.

Abstract: A method is disclosed for casting a concrete product using two or more different grades of concrete mix, in which method predetermined amounts of different grades of concrete mix are delivered at appropriate instants into the feeder hopper of the slip-form casting machine.

Abstract: A thermoprocessable copolymer of TFE essentially formed by: (a) from 4.5 to 8.5% by weight of perfluoromethylvinylether (PMVE); (b) from 0.3 to 1.6% by weight of a perfluorodioxole of formula: wherein: Y=F, ORf, Rf wherein Rf is a perfluoroalkyl having from 1 to 5 carbon atoms; X1 and X2, equal to or diferent from each other, are —F or —CF3; (c) TFE, forming the remaining part to 100%.

Abstract: An array of dies having a closed configuration is used in a method and apparatus for making a closed composite article that comprises multilayered materials. In the method and apparatus, at least two extruders are used to extrude at least two material streams through the die array to provide an extrudate comprised of alternate layers of material from the at least two material streams. The compositions in the two material streams can be the same or different.

Abstract: A method is provided for fabricating a concrete slab in a substantially horizontal slip casting process method, concrete mix is fed into a mold through a delimited cross section moving progressively in the casting process so as to form a concrete product of a desired shape. Onto the surface of the casting bed (1) is placed a core (3, 9, 10, 11) capable of delimiting the cross section of the concrete product (5, 5?) so as to provide an opening or a provision for an opening in the bottom surface of the slab. A core is provided for obtaining an opening or a provision for an opening. The structure and/or material of the core is/are such that the core is capable of yielding in vertical direction. A core may also be a multipart core, the outer part of which becomes detached from the inner part of the core in conjunction with lifting off the concrete slab from the casting bed.

Abstract: A process for preparing polyethylene thin films is disclosed. The process comprises extruding a blend that comprises a linear low density polyethylene (LLDPE) and a high molecular weight, high density polyethylene (HMW-HDPE) or high molecular weight, medium density polyethylene (HMW-MDPE). The blend has an LLDPE/HMW-HDPE or HMW-MDPE weight ratio at least 50/50. The blend is extruded through an annular die to form a molten material tube. The molten material tube is then pulled around a flexible internal orientation device (FIOD) to form the film. The FIOD makes it possible to prepare polyethylene thin films from LLDPE-rich LLDPE/HMW-HDPE or HMW-MDPE blends on a high stalk film line. The films have increased machine-direction (MD) tears.

Abstract: A method and apparatus are for fabricating a concrete product in a slip-form casting process, in which method concrete mix is fed into a slip-form mold of a defined cross section moving progressively in the casting process so as to obtain a concrete product of a desired shape. The method includes an interruptible guidance control of the prestressing tendons so as to allow the tendon guides to travel past supplementary parts such as reinforcing steels connected to the prestressing tendons.

Abstract: In order to manufacture a discharging roller which discharges a recording medium from a recording apparatus, there are a first die formed with a first recess extending in an axial direction of a shaft portion of the discharging roller, and a second die formed with a second recess extending in the axial direction. The first die and the second die are combined such that the first recess and the second recess face to form a continuous cavity. Synthetic resin is injected into the cavity to mold a bore portion of the shaft portion.

Abstract: To provide a tire tube having excellent sealing performance and durability. An inside of a tire includes a peripheral wall having an approximately circular cross-section which is partitioned by a partition wall into an outer peripheral side sealant chamber and an inner peripheral side air chamber. The sealant chamber is filled with a sealant having a thickness in the diameter direction in a range of 0.5 to 1.5 mm.

Abstract: A balloon blowing process which involves radial expansion of an extruded tubing segment which has been subjected to a stretching step prior to radial expansion, the process utilizing an internal pressure and a temperature which together cause at least a portion of the tubing to expand to an interior diameter (ID) which is greater than the interior diameter of the extruded segment prior to extrusion.

Abstract: A method is provided are for fabricating a concrete product in a substantially horizontal slip-form casting process, in which method concrete mix is fed into a slip-form mold of a defined cross section moving progressively in the casting process so as to give a concrete product of a desired shape. The input power need of the concrete mix feed and compaction is measured, whereupon the travel resistance of the casting machine is controlled based on the value of a measured process variable. Therefore, quality variations in a slip-form cast product that are caused by changes in the density of the concrete mix and the travel resistance of the casting machine are eliminated.

Abstract: A method for the production of prestressed concrete products and a plant for implementing the method. Moulds provided with pretensioned wires are moved through fixed casting machines into a hardening space. In the hardening space, the combination of mould and product is lifted sideways from the casting line before hardening, using synchronised lifting equipment. The combination may be stacked for space economy. After hardening, the product is removed from the mould using the same lifting equipment. The moulds are returned to the beginning of the casting line, during which stage they are cleaned and refurbished. The products are transferred to cutting and finishing stations.

Abstract: A method is disclosed for casting a concrete product, in which method the concrete product is cast in an essentially horizontal slipform casting process during which the top surface height and profile of the concrete product being cast is measured continually. Based on the measurement results, the relative proportion of the concrete mix flowing to the upper layer or lower layer of the concrete product is controlled by way of moving or tilting a feed trough (12) located below the concrete mix feed means (2).

Abstract: A polymeric binder system and method of making, and a method for extruding thin-walled articles such as thin-walled tubes is provided. The extrusion method comprises providing a polymeric binder system comprising a substantially homogeneous solution of a polymeric binder and an organic solvent, adding a ceramic or metal powder to form a mixture, and evaporating the solvent from the mixture. The remaining mixture is then extruded from a die and heated to burn-off the binder and sinter the article.

Abstract: An elongate polymer member having molecular helical orientation formed by rotation immediately after passing through the extrusion head. The elongate polymer member is rotated downstream of the extrusion head in the molten state prior to solidification in order to impart the molecular helical orientation. Rotating the polymer member in the molten state allows the helical orientation to be imparted at the molecular level, and allows for more rotations per lineal foot of extrusion.

Abstract: An extrusion die has a distributing tool; a profiling nozzle; and at least three melt-flow ducts; a first melt-flow duct is routed around a second melt-flow duct or the distributing tool using a branch and is merged again downstream from the branch; and a third melt-flow duct opens into the second melt-flow duct. The extrusion die is suitable for extrusion of a hollow-chamber profiled panel of a thermoplastic plastic with a layered structure which comprises a top and bottom layer of a first plastic melt; and an intermediate layer of a second plastic melt disposed in an interior of a hollow chamber profile. The first plastic melt is allocated to the first melt-flow duct and to the second melt-flow duct and the second plastic melt is allocated to the third melt-flow duct. During the extrusion the second plastic melt is deposited onto the first plastic melt upstream from or in the region of the branch, and a distribution of the deposited second plastic melt is regulated using the distributing tool.

Abstract: A process for producing a low-profile, high-strength dilatation catheter balloon is disclosed. The process comprises forming a tubular extrudate and quenching said extrudate in a cryogenic fluid. The quenched extrudate has morphology of a largely disordered material. The crystallinity in the extrudate is no more than 15%. The crystallinity of the extrudate is measured using X-ray crystallography or DSC. The extrudate is further processed in a mold in which the extrudate is longitudinally and radially stretched. The stretched extrudate is finally attached as a balloon to the distal end of a catheter.

Abstract: The invention is a method for the late introduction of additives into polyethylene terephthalate. The method employs a reactive carrier that functions as a delivery vehicle for one or more additives. The reactive carrier reacts with the polyethylene terephthalate, thereby binding the reactive carrier in the polyethylene terephthalate resin and preventing the emergence of the reactive carrier and additives from the polyethylene terephthalate during subsequent thermal processing.

Abstract: High flux porous hollow fiber membranes are produced from perfluorinated thermoplastic polymers by extruding heated solution of the polymer having a lower critical solution temperature directly into a cooling bath to form the porous membrane by liquid-liquid phase separation. Extrusion can be conducted either vertically or horizontally.

Abstract: High flux porous hollow fiber membranes are produced from perfluorinated thermoplastic polymers by extruding a heated solution of the polymer having a lower critical solution temperature directly into a cooling bath to form the porous membrane by liquid-liquid phase separation. Extrusion can be conducted either vertically or horizontally.

Abstract: The present invention relates to processes for fabricating polymeric hollow fibers. Specifically, a removable solid core fiber is provided for coating one or more layers of a polymeric membrane-forming material thereon. After treating the polymeric membrane-forming material layer to form a solidified polymeric membrane having a permanent tubular shape, the solid core fiber is selectively removed, leaving an elongated lumen inside the solidified polymeric membrane, which forms a high quality polymeric hollow fiber that is substantially free of deformation defects. The solid core fiber can be made of a removable substrate material, such as water-soluble polymers polyvinyl pyrrolidone (PVP), polyvinyl alcohol (PVA), or polyethylene glycol (PEG), which are subsequently and selectively removable by water. Alternatively, the solid core fiber can be coated with a removable substrate material, which imparts removability to such solid core fiber.

Abstract: A method for manufacturing multiple channel membranes includes extruding a polymer solution through an extrusion nozzle wherein several needles are arranged through which a gas or liquid containing a coagulating agent is injected during extrusion, wherein the outer side of the extruded material is first brought into contact with a mild coagulation agent and subsequently with a strong coagulation agent. By using the method a membrane is obtained having parallel channels extending in extrusion direction, in which an active layer is situated in the channels, whereas the outer surface with respect to the active layer has no or hardly any resistance to flows of liquid. By using the method it is possible to make shapes, such as recessed portions, in the membrane circumference. Also disclosed is the use of such membranes in filtration and separation techniques.

Abstract: A processing technique and a composition which allow compositions of PBT polymers or copolymers to be formed into blow molded articles, especially medical balloons such as dilatation or stent placement balloons, from extruded tubular parisons. The process includes a longitudinal stretch step run at a temperature below the Tg of the polymeric material and a radial expansion step run at a temperature above the Tg of the polymeric material. During the longitudinal stretch step, the tubing is subjected to high internal pressure. In the composition a small amount of boric acid is added to the polybutylene terephthalate in a melt blend to give a formulation which has reduced crystallinity after extrusion and which can more readily fashioned into high strength blow molded articles than PBT by itself. Articles, which may be formed using the invention include medical device balloon articles in which the polymer consists essentially of PBT optionally blended with boric acid.

Abstract: A tubular food casing of a tubular cellulose film precipitated from a viscose solution having a viscosity of from about 55 to about 90 ball seconds, where the ball has a density of 8 g/cc and a radius of 0.316 centimeters at a drop of 20 centimeters, and where the solution contains at least eight and one-half weight percent of cellulose. The cellulose has a DPv of from about 300 to about 525 and the cellulose film has a dry film thickness of from about 0.015 mm to about 0.040 mm, a dry burst pressure in excess of 40 cm Hg, per 0.01 mm of dry film thickness, and a rewet burst pressure in excess of 5 cm Hg per 0.01 mm of rewet film thickness.

Abstract: An apparatus for removing NMMO-water mixture which collects in the interior of a tubular film which is produced by the NMMO process comprises a spinning vat and a wash vat. Between the two vats is situated a conveyor belt which circulates endlessly over two rollers. The conveyor belt is directed upward at an incline from the spinning vat to the wash vat. The tubular film, in the interior of the spinning vat, is passed vertically downward, then reversed and conducted vertically out of the spinning vat and passes over the inclined conveyor belt into the wash vat. Above the conveyor belt is situated a spray device having spraying nozzles from which wash liquid at a temperature between 60 and 80° C. is sprayed onto the tubular film which is transported via the conveyor belt.

Abstract: A method of forming graphitic bodies comprises the steps of:—

Abstract: A rubber hose having a multilayer wall is formed of an inner layer of NBR type rubber having a high AN content, available at a low cost and highly impermeable to fuel and an outer layer of a rubber composition having a minimum Mooney viscosity of 25 to 65 at its curing temperature and highly resistant to flattening. Those layers are extruded and cured together without the aid of any mandrel owing to the inside diameter and wall thickness of the hose and the thickness of the outer layer which fall within specific ranges. This process enables the manufacture of a fuel hose having a high fuel impermeability at a low cost, while protecting its inner wall effectively from flattening during curing.

Abstract: Process for producing formed cellulosic articles, such as fibers, filaments, sheetings, membranes or tubes, comprising a) extruding a solution of cellulose in an aqueous amine oxide, particularly N-methylmorpholine N-oxide, through an extrusion die via an air gap and coagulating the formed article in an aqueous precipitation bath containing amine oxide, and b) passing the formed article through at least one washing stage for removing residual amine oxide from the article, characterized in that the liquor of the precipitation bath in the precipitation stage and/or the washing liquor of the washing stage(s) is treated with ultra-violet radiation. In this manner the formation and growth of coatings, films and slime deposits caused by microorganisms is avoided on parts of the plant which come into contact with said liquors containing the amine oxide.

Abstract: Solvent-resistant polybenzimidazole membranes, methods of making them and crosslinking them and composite membranes and hollow fiber membrane modules from them are disclosed.

Abstract: The present invention provides improved medical introducer devices which incorporate a single or multi-layer PTFE peelable sheath. Devices of the present invention are suitable for use in inserting an ancilliary medical device, e.g., a catheter, guide wire and the like, into a patient. Methods of the present invention also are disclosed which employ a precision sintering process in order to produce sheaths having excellent tear properties and optimal peelability.

Abstract: The invention relates to a system and method for localized drug delivery. The system includes a catheter and stylet. The catheter has a set of inwardly extending portions that function to provide structure to the catheter wall, prevent collapse or closure of the catheter lumen, and enable easy withdrawal of the stylet. The inwardly extending portions may take the form of substantially triangular shapes, semicircular, circular or other shapes. With the present invention, a catheter may effectively be installed in a patient in a proper location. The location may be tested through the transfer of fluid through the catheter while the stylet is in place during surgery. The catheter may be tightly sutured in place and the stylet easily withdrawn.

Abstract: Process for producing fibres, film, casings and other products from modified soluble cellulose wherein the initial cellulose is hydrothermally treated at a temperature in the 100-200° C. range, under a pressure in the range from about 0.1 to 1.5 Mpa in a water/cellulose ration on a weight basis of at least 1:1 in the presence of a complex activator composed of Lewis acids and/or bases and/or their salts in an amount of at least 0.0001% by weight calculated on cellulose. The obtained modified cellulose pulp after, a possible purification, is in a dry or never dried condition, dissolved in an aqueous solution of alkali metal hydroxides. The dissolving is carried out at a temperature not lower than 0° C. for 1-120 minutes to obtain a homogenous spinning solution with the cellulose concentration at least 1% by weight. The alkaline cellulose solution is filtered, deaerated and coagulated by contacting it with water or aqueous acidic solutions.

Abstract: Environmentally degradable molded or extruded articles comprising a polyhydroxyalkanoate C4C6 copolymer composition having short annealing cycle times are provided. Such short annealing cycle times are achieved by compositions having a percentage of C6 units of 2-8%. Desirable annealing cycle times are obtained for molded or extruded articles, particularly for tampon applicators.

Abstract: A method and apparatus for manufacturing a rubber sheet containing short fibers. The method includes the steps of: mixing short fibers in a flowable rubber matrix; forming the flowable rubber matrix with the fibers therein into a cylindrical shape with a circumferential extent; separating a portion of the circumferential extent from the cylindrical shape, and forming the cylindrical shape with the portion separated into a sheet form.

Abstract: An extruder apparatus and method for producing an extruded tubing having varying inner dimensions without changing the outer dimensions. The tubing is forced from the die face of an extrusion head having an extruder die and an internal mandrel determining the outer and inner dimensions, respectively, of the extruded tubing. The outer dimensions of the mandrel varied by the user to change the inner dimensions of the extruded tubing. A pressure is maintained in the extruded tubing to prevent its collapse and that pressure is changed based upon the change of the external dimensions of the mandrel and the wall thickness of the tubing. In one embodiment, the mandrel is comprised of a core and a plurality of telescoping sleeves. Each sleeve is movable between a retracted position where the sleeve is displaced away from the die face and an extended position where sleeve is at the die face. There may be multiple mandrels in the case of multi-lumen catheters.

Abstract: The invention relates to a method of manufacturing a reinforced oblong concrete product for longitudinal load-bearing purposes, in particular a driving pile. According to the present invention reinforcing fibers are used to prevent break-up of the concrete due to radial forces which occur during driving, and the concrete composition is provided with said reinforcing fibers before the concrete composition is applied to the reinforcing wire. This method reduces the amount of heavy labour and cost. The invention also relates to a driving pile comprising reinforcing fibers.

Abstract: The present invention discloses an extrusion die module having a flat compression seal surrounded by a conical or otherwise angled spillover surface. The die module promotes a flat surface to flat surface compression seal outside of the flow distribution channels and promotes better streamlined flow and material combination than a traditional flat disk die module. The die module promotes a reduced overall diameter and wetted diameter in comparison to standard flat disk dies. In addition, the present invention relates to an extrusion die module having a spillover surface surrounding a planar sealing surface. Further, the present invention relates to a method for utilizing an extrusion die module with a conical or otherwise angled spillover surface to minimize the die surface area wetted by an intermediate layer in a multi-layer coextrusion process.

Abstract: A thin wall PTFE tube is formed from an extruded green tube. The PTFE tube includes an inner tubular surface and an opposed outer tubular surface defining a tubular wall of a first thickness. The tubular wall is compressed to uniformly reduce the wall-thickness and circumferentially orient the tube. The PTFE tube is positioned over a first elongate roller with the inner tubular surface being in contact therewith. A second roller is positioned against the outer tubular surface of the PTFE tube. The pair of rollers are counter rotated so as to circumferentially compress the tubular wall between the rollers. This results in the uniform reduction in the tubular wall from the first thickness to a lesser second thickness and a circumferential orientation otherwise not occurring in an extruded PTFE paste extrusion.

Abstract: The present invention discloses an extrusion die module having a flat compression seal surrounding a conical or otherwise angled spillover surface. The die module promotes a flat surface to flat surface compression seal outside of the flow distribution channels and promotes better streamlined flow and material combination than a traditional flat disk die module. The die module promotes a reduced overall diameter and wetted diameter in comparison to standard flat disk dies. In addition, the conical or angled spillover surface is surrounded by the planar sealing surface. Further, the present invention relates to a method for utilizing an extrusion die module with a conical or otherwise angled spillover surface to minimize the die surface area wetted by an intermediate layer in a multi-layer coextrusion process.

Abstract: The present invention discloses an extrusion die module having a flat compression seal and a conical or otherwise angled spillover surface. The die module promotes a flat surface to flat surface compression seal outside of the flow distribution channels and promotes better streamlined flow and material combination than a traditional flat disk die module. The die module promotes a reduced overall diameter and wetted diameter in comparison to standard flat disk dies. Further, the present invention relates to a method for utilizing an extrusion die module with a conical or otherwise angled spillover surface to minimize the die surface area wetted by an intermediate layer in a multi-layer coextrusion process.

Abstract: In an extruder for producing a polytetrafluoroethylene tube having a minimum thickness deviation by extruding a polytetrafluoroethylene paste through an annular portion formed by a core pin (30) and a die orifice (50) around it, the core pin comprises a mandrel connection end (34) which is connected to a mandrel and a die orifice outlet end (36) which is located at a die orifice outlet end, and the core pin has between the ends a portion of which cross-section perpendicular to an axial direction of the core pin has a smaller area than that of a cross-section of each end of the core pin. By using the extruder, the tube having a thickness deviation of not larger than 15% can be obtained.

Abstract: Using a mold equipped with a rib-forming member capable of moving forward and backward relative to the mold cavity, produced is a lightweight, hollow resin molding having a reinforcing rib structure in the hollow area, from a fiber-containing thermoplastic resin having a fiber content of from 10 to 70% by weight. To produce the molding, a melt of a fiber-containing thermoplastic resin is injected into the mold cavity or is injected thereinto under compression, then the movable mold member is moved backward in the direction in which the mold cavity is expandable, and after the start of the mold member moving, a gas is introduced into the resin melt. Even though the molding has a hollow structure and has a large surface area, it has good stiffness and high strength, and has good appearances. The weight of the molding can be well controlled and reduced to any desired degree. The molding has many applications in various fields.

Abstract: Solvent-resistant polybenzimidazole membranes, methods of making them and crosslinking them and composite membranes and hollow fiber membrane modules from them are disclosed.

Abstract: A coating device for coating an interior surface of a continuous tube of material with a fluid. The coating device includes an extruder die for forming the continuous tube of material and a fluid delivery system. The fluid delivery system is positioned within the extruder die so as to introduce the fluid onto the interior surface of the continuous tube of material.

Abstract: A process for preparing a container for handling a household waste material which involves molding a household waste container from a plastic batch material containing 0.1 to 10% by weight of at least one phenol biocide selected from the group consisting of 5,5′-dichloro-2,2′-dihydroxydiphenyl methane, 3,5,3′,5′-tetrachloro-4,4′-dihydroxydiphenyl methane, 3,5,6,3′,5′,6′-hexachloro-2,2′-dihydroxydiphenyl methane, 5,5′-dichloro-2,2′-dihydroxydiphenyl sulfide, 2,4,5,2′,4′,5′-hexachloro-dihydroxydiphenyl sulfide, 3,5,3′,5′-tetrachloro-2,2′-dihydroxydiphenyl sulfide, and 2,4,4′-trichloro-2′-hydroxydiphenyl ether to form the container with an inner and an outer co-extruded layer wherein the phenol is applied on a co-extruded layer forming the surface of the inner co-extruded layer.