Abstract: A molded article of fluorine-containing polymer, especially of polytetrafluoroethylene, with increased water-repellency, and a jig for holding articles to be washed during washing processes using an aqueous washing medium. The molded article with superior water-repellency can be obtained by a treatment of the surface of fluorine-containing polymer with a fluorine-containing gas after roughening of the surface. The water-repellent jig made of the surface treated polytetrafluoroethylene is suited for use as a carrier for washing semi-conductor wafers and glass plates or guide rolls of a liquid crystal display device.

Abstract: In a fiber composite plastic composed of plastic composition and fibers, the fibers have a pronounced fiber length distribution, in particular more than 50% by weight of the fibers have a length outside the range from 0.8.times.L to 1.2.times.L, where L is the mean (weight average) fiber length, and the mean fiber length is greater than the critical fiber length of the plastic composition/fiber system.

Abstract: A method of making the tile dispenses wet concrete having two different colors into a partitioned pug box for disposition onto opposite sides of a pallet, so that, the two different colors reside on opposite sides of the pallet in side-by-side relation. The wet concrete is metered and compressed by a roller and shaped by a slipper to provide the concrete tile with a desired cross-sectional shape, following which the concrete is then chopped by a knife assembly to form the individual tiles with desired edge configurations. The concrete is cured and then removed from the pallets to form the completed tiles. The method may be incorporated into a continuous process in which a succession of the pallets are passed by a conveyor beneath a making head assembly containing the partitioned pug box and the roller and slipper and then beneath a knife assembly to form a succession of the concrete tiles.

Abstract: An elastomeric article having a matte finish is prepared by curing a hydrolyzable composition under conditions of elevated humidity, or by including short aramid fibers therein. Disclosed herein are particular processes for the preparation of matte finished silicone rubber articles in a continuous extrusion process.

Abstract: A method of manufacturing a monolayer heat-shrinkable, puncture-resistant biaxially oriented film is disclosed. The method includes a double bubble orientation step and extruding a primary tube that includes at least one substantially linear ethylene homopolymer or interpolymer, wherein the substantially linear ethylene homopolymer or interpolymer has an uniform branching distribution, a melt flow ratio I.sub.10 /I.sub.2, .gtoreq.5.63, and a molecular weight distribution, M.sub.w /M.sub.n, defined by the equation M.sub.w /M.sub.n .ltoreq.(I.sub.10 /I.sub.2)-4.63, and is also characterized as having essentially no linear polymer fraction, a single DSC melting peak, a density greater than about 0.85 g/cc, and a favorable gas extrusion critical shear rate at the onset of surface melt fracture.

Abstract: A method for making a film which is useful in the packaging of newly formed blocks of cheese and demonstrates flexibility, extensibility, and improved sealing strength comprises extruding an ethylene vinyl acetate/very low density polyethylene sealing layer. In addition to barrier properties, flexibility and extensibility are, preferably, also provided by coextruding a core layer of ethylene vinyl alcohol copolymer containing at least 32% by weight of ethylene with the sealing layer.

Abstract: The present invention provides a method of making an orthopedic casting article comprising an apertured, extruded sheet. The method involves the steps of charging an extrudable material selected from the group consisting of low temperature thermoplastic polymers and viscous curable resins to an extruder; and extruding the material through a die to form an apertured sheet. The sheet is used as an orthopedic casting material and has a sufficient number of apertures after application to the patient to allow moisture vapors produced by the skin to freely escape through the cast or splint. The sheet preferably has at least 20 percent aperture volume. The apertured, extruded sheet may optionally contain a filler associated with the resin. The incorporation of fillers adds substantially to the strength of the cured casting material as well as to the handling properties of the uncured casting tape or bandage.

Abstract: A method of manufacturing a multilayer heat-shrinkable, puncture-resistant biaxially oriented film is disclosed. The method includes a double bubble orientation step and extruding a primary tube that includes at least one substantially linear ethylene homopolymer or interpolymer, wherein the substantially linear ethylene homopolymer or interpolymer has an uniform branching distribution, a melt flow ratio, I.sub.10 /I.sub.2,.gtoreq.5.63, and a molecular weight distribution, M.sub.w /M.sub.n, defined by the equation M.sub.w /M.sub.n .ltoreq.(I.sub.10 /I.sub.2)-4.63, and is also characterized as having essentially no linear polymer fraction, a single DSC melting peak, a density greater than about 0.85 g/cc, and a favorable gas extrusion critical shear rate at the onset of surface melt fracture.

Abstract: A method of making a disposable tubular device comprising extruding a first material through a first die to form the tube and moving the tube through the second die while extruding a second material through the second die to form the tube-support structure. The second material has a surface hardness which is greater than the surface hardness of the first material.

Abstract: A method is disclosed for molding parts. The system comprises a plasticator and press. The plasticator is capable of receiving a plurality of molding materials comprising a predetermined amount of at least thermoplastic polymers and long reinforcing fibers, such as glass fiber. The plasticator is characterized in that it is capable of simultaneously receiving contaminated molding materials and relatively long glass fibers and molding them into a billet wherein the fibers remain substantially undamaged. The billet is subsequently placed in a compression molding press where other materials may be molded or applied to its surface. The method is further characterized in that a single thermal rise is used to plasticate the molding materials.

Abstract: A liquid resin composition prepared by mixing an ionic material and/or a chargeable material into a thermosetting or thermoplastic resin is injected into a mold having a predetermined inner shape, and a DC voltage is applied to the liquid resin composition to concentrate the ionic material and/or chargeable material on a desired portion or to distribute the ionic material and/or chargeable material continuously. Thereafter, the resin composition is thermally cured when the resin composition contains the thermosetting resin, or the resin composition is hardened by cooling when the resin composition contains the thermoplastic resin, thereby obtaining a molding having a predetermined shape.

Abstract: An annular culture vessel for growing mammalian cells is constructed in a one piece integral and annular configuration with an open end which is closed by an endcap. The culture vessel is rotatable about a horizontal axis by use of conventional roller systems commonly used in culture laboratories. The end wall of the endcap has tapered access ports to frictionally and sealingly receive the ends of hypodermic syringes. The syringes permit the introduction of fresh nutrient and withdrawal of spent nutrients. The walls are made of conventional polymeric cell culture material and are subjected to neutron bombardment to form minute gas permeable perforations in the walls.

Abstract: A method and apparatus for producing plastic products from waste materials by: cutting into pieces a thermoplastic material having a loss factor higher than 0.005 such as to have a high absorbence of radio-frequency radiation, mixing the pieces with at least one other particulate material, depositing the mixture on a supporting surface; applying radio-frequency radiation to the mixture sufficient to soften mainly the outer surfaces of the pieces of thermoplastic material by dielectric heating, while applying pressure to the mixture to bond the mixture together by sintering; and removing the sintered mixture from the supporting surface.

Abstract: A method utilizing melt processing for making a unified, composite tape structure that includes two outer pressure-sensitive adhesive layers and a backing wherein at least one of the two outer adhesive layers is not mutually coextensive.

Abstract: A process for preparing molded articles of a polyimide is provided the steps of melting and extruding, at 50.degree. to 100.degree. C., a polyimide precursor composition for extrusion molding of a polyimide which includes 30 to 60% by weight of a polyimide precursor (c) obtained by reacting an aromatic tetracarboxylic dianhydride or its derivative (a) with an aromatic diamine or its derivative (b) in a good solvent of the polyimide precursor and then depositing the resultant polyimide precursor solution in a poor solvent of the polyimide precursor, 0.1 to 5% by weight of the poor solvent, and 35 to 69.9% by weight of the good solvent, and then heating the molded composition at 250.degree. to 500.degree. C. to imidate the same or its derivative (b) in a good solvent of the polyimide precursor and then depositing the resultant polyimide precursor (c) solution in a poor solvent of the polyimide precursor, 0.1 to 5% by weight of the poor solvent, and 35 to 69.

Abstract: A conduit assembly (10) is manufactured by extruding a casing (11) through a die while at the same time feeding a web member (15) into the casing (11) as it is being extruded to form a plurality of chambers (16, 17). If the conduit assembly (10) is manufactured with a line, such as a rope (18) or a cable (19), the rope (18) and/or cable (19) is likewise fed into the casing (11) adjacent to the web member (15) into one or both of the chambers (16, 17).

Abstract: Medical device tubing is prepared from a blended polymer which is a blend of polyetheramide having substantially no ester linkages together with either or both of a polyamide and a polyesteretheramide having a hardness of at least about Shore 70D. The resulting tubing has an exceptionally high ratio of burst strength to flexibility, and the blended polymer retards blooming of the tubing that is believed to result from migration of monomers to the surface of the tubing.

Abstract: A process for preparing a biodegradable water-resistant film. The process includes the steps of dispersing zein in an aqueous solution comprising acetone in an amount of from 65 to 75% by volume to form a zein dispersion, forming the resulting zein dispersion into a film, and drying the film in an atmosphere having a relative humidity of 85% or less at an initial temperature of 55.degree. C. or less. The present invention also relates to a method for imparting water resistance to an article with poor water resistance by coating the article with the zein dispersion prepared as above, and drying the coated zein dispersion under the above conditions. The film or coating film according of the present invention neither dissolves upon contact with water, nor becomes weak due to water absorption or swelling on contact with water.

Abstract: A method for the manufacture of low cost "oriented" composite molding compounds using discontinuous fibers embedded in a resin matrix. The method involves the steps of aligning discontinuous fibers by use of a strong electric field while simultaneously inserting the fibers onto a polymer substrate comprised of an uncured resin matrix. A preferred embodiment includes the incorporation of a mesh or a glass capillary array located parallel and adjacent to the polymer substrate to further ensure fiber alignment. After the fibers are attached to the uncured resin matrix, the aligned fibers are forced to lie down parallel along the surface of the polymer substrate by mechanically forcing the fibers flat. The newly formed reinforced polymer films may then be stacked with the fibers of each ply oriented to achieve the desired mechanical properties, and then cured to produce an improved composite laminate which can be machined to form a high strength shaped member.

Abstract: An extrusion assembly for extrusion of a triple walled (plastic/metal/plastic) pipe includesa first extrusion apparatus, for extruding an inner plastics layer of the pipe, having an extruder with a coaxial outer extrusion sleeve and inner extrusion die,a shaping sleeve surrounding and substantially coaxial with the extruder, which shaping sleeve is capable of shaping a U-section form metallic layer passing through it into a tubular configuration and a welder for welding the metallic layer of tubular configuration to provide a metal tube,a conduit for supplying a pressurized gas internally of the pipe whereby extruded plastics material emerging from the first extrusion apparatus is forced against an internal surface of the metal tube, anda second extrusion apparatus, for extruding an outer plastics layer of the pipe, having a body part and a supply channel within the body part for supplying plastics material,which extrusion assembly has at least one of,(a) an essentially annular section recess in the body part