Abstract: The invention relates to films and tubular structures which are selectively permeable to liquids and gases which are based on a copolymer composed of a copolymerized fluorinated olefin, copolymerized vinyl acetate and, optionally, a copolymerized olefin. It is possible for the acetate groups of the copolymer to have been saponified to form OH groups. The films or tubular structures have in each case an inherent, latent capacity for modifying their structure and are at the same time oleophobic and oleophilic. The invention also embraces processes for the preparation of the shaped articles described and processes for modifying their structure. The invention also relates to the use of shaped articles according to the invention.

Abstract: A method of producing a thermoplastic sheet or film characterized in that a molten thermoplastic resin sheet extruded through a T-die is cooled by introducing it into a multi-stage slit in which a cooling water is flowing. The water level in the first slit of the multi-stage slit is maintained at as low a level as possible. The method produces various advantages over conventional methods; for example, the sheet or film is free from unevenness in thickness, wrinkles, and curls, and is of high uniformity, and the sheet or film can be formed by high-speed molding of at least 10 m/min. The sheet or film is suitable for use in wrapping of, for example, foods and medicines.

Abstract: A vat under vacuum bears in its sidewall a sizing sleeve, the cylindrical downstream portion of which includes annular channels interconnected by distribution channels. Injection ducts leave the bottoms of the annular channels and open out in the inside surface of the sleeve. The interior of the sleeve communicates with the interior of the vat via rows of radial suction ducts. During operation, the injection ducts are supplied with water under pressure which forms a film between the outside of the tubing and the inside surface of the sleeve even when the tubing is pressed against that inside surface owing to the partial vacuum prevailing within the vat.

Abstract: Polyamide plastic fuel lines which are dimensionally stable and resistant to fuels, alcoholic fuels and alcohols as fuels are prepared from aliphatic high molecular weight polyamides. The fuel lines are prepared by extruding a hot melt of the polyamide, sizing through a die having a diameter in excess of the given diameter of the fuel line, cooling the fuel line in a cooling bath, removing the fuel line from the bath and sizing the fuel line adiabatically through a disk having a diameter less than the given diameter.

Abstract: The pitch is extruded at a suitable temperature through cylindrical nozzles. At the exit from these nozzles the pitch is lowered into water, where a cutter divides it into granules which, deposited on a conveyer belt, remain immersed long enough to permit suitable cooling. Then they undergo drying by hot jets of air.

Abstract: The film (11) extruded from a vinylidene fluoride polymer is subjected to a stretching of at least 200% while still in the molten state, and then cooled rapidly to a temperature below 50.degree. C.The equipment comprises, in series, an extruding device (1) (2), a cooling device consisting of a thermostatically controlled liquid bath (6), the level of which is located at a distance of 10 to 300 mm from the extruding device, and a device (8) (9) for stretching the extruded film by at least 200% in its part located between the extruding device and the cooling device.The film obtained is suitable for manufacturing piezoelectric films.

Abstract: The present invention relates to a process for producing an of aromatic polyimide film comprising (A) casting on a support a dope containing an amide-type polar solvent and 10-45 weight percent of a polyamic acid having more than 0.4 dl/g an inherent viscosity of more than 0.4 dl/g, (B) concentrating the polymer content to be at least higher than that of the initial dope while simultaneously raising the ring closure ratio above 30%, (C) removing the solvent from the film by extraction in an aqueous medium so as to lower the solvent content of the film below 10% and (D) then heating the film to a temperature of more than 200.degree. C.The process of the present invention is useful for the production of aromatic polyimide film having a reduced rate of solvent decomposition and improved productivity.

Abstract: A process and system for the formation of a polymer foam sheet of comparatively uniform biaxially orientation and comparatively uniform dimensions prepared by extruding polymer foam so that it rides on a fluid bearing film between the point of extrusion and a point of diameter expansion of the extruding tube.

Abstract: The present invention concerns a procedure for precipitating cellulose carbamate from an aqueous alkali solution. The solution is brought into contact with an aqueous solution of sulphuric acid containing one or several cations selected from the group consisting of Na, Al, Mg, Zn and Ca cations, whereby in the precipitation of cellulose carbamate the advantage is gained that the dry matter content of the fibre can be made high enough.

Abstract: A polyethylene terephthalate packing band is provided which is made of a polyethylene terephthalate resin having an intrinsic viscosity of 0.90 to 1.20 and has been longitudinally stretched to an overall draft of 3 to 6 times. There is also provided a packing band of the above construction in which the longitudinal orientation of the resin molecules has been randomized by embossing. There is further provided a method by which the above-mentioned packing band is efficiently manufactured.

Abstract: Process for continuously curing an elastomeric jacket on a cable, comprising continuously passing a cable having an uncured elastomeric jacket thereon, encased within an outer temporary mold of heat conductive metallic material, e.g. metallic lead, of sufficient encasing layer thickness for protectively confining and supporting therewithin the elastomeric jacket and cable thereat, through a vulcanizing zone maintained at substantially atmospheric pressure and provided with a heat transfer bath, e.g. a fusible mixture including sodium nitrate, sodium nitrite, potassium nitrate and potassium nitrite, while applying the bath to the cable at a selective bath temperature, e.g. about 400.degree.-500.degree. F., sufficient for vulcanizing the mold encased elastomeric jacket in situ during passage of the cable through the zone whereby to vulcanize the jacket in situ substantially free from stress, damage or disturbance, and with subsequent cooling thereof prior to removal of the mold therefrom.

Abstract: An unmanned pelletizing device for plastic material for preventing the breakage of strands of the plastic material formed between a cooling roll and a pinch roll. The cooling roll is partially submerged in a tank of cooling water. A cutter includes a fixed knife having a plurality of grooves formed therein for registration with the plastic strands.

Abstract: Turbulence members made of a synthetic resin are manufactured by a method which comprises melting a synthetic resin and causing the molten resin to be rotated around its axis and at the same time extruded in a state wherein the molten resin is spirally twisted by use of an extruding means provided with a rotary nozzle having a slit, passing the extruded molten resin under water in a cooling means thereby cooling and solidifying the extruded resin and drawing the resultant resin with a drawing means. The cooling means is provided with a relatively narrow and relatively wide chamber to facilitate uniformity and efficiency of production.

Abstract: An eraser based on polyvinyl chloride having particles of a crosslinked polymeric natural or synthetic rubber embedded in the polyvinyl chloride structure. Such erasers have high strength and good aging resistance. Additionally, conventional softeners in the eraser do not undergo significant migration and consequently, the eraser does not smudge. A process for manufacturing the eraser is also disclosed.

Abstract: The abrasion resistance and tensile strength of asbestos is significantly improved by the addition of significant amounts of metal oxides, such as iron oxide, under conditions to provide at least some surface bonding of the oxides to the surface of the asbestos. The oxides are preferably added during formation of bodies from asbestos dispersions and also impart color to the final product.

Abstract: A sewer pipe, transport pipeline, or other circumferentially enclosed passageway is lined by inserting into and along it a flexible tubular material of given diameter, with its corresponding circumference being less than the inside perimeter of the passageway. The tubular material is a laminate having a dimensionally stable skin layer facing the interior of the passageway and a contiguous layer of a composition foamable to form an expanded cellular structure. After insertion of the tubular material the contiguous layer is foamed to expand cellularly so as to fill the space between the inner skin and the inside wall of the passageway and to solidify in place. The tubular material may have an expansible outer skin layer also.

Abstract: A semipermeable membrane made of a polyaryl ether sulfone comprised of recurring units represented by the general formula (I): ##STR1## wherein X, X', X" and X'" are non-dissociative substituents, and l, m, n and o are integers of from 0 to 4. The membrane, which is composed of a single continuous polymer phase, has pores of a diameter increasing progressively and continuously from the surface layers to the center portion thereof.The membrane is prepared by the process wherein:the polyaryl ether sulfone is dissolved in a mixed solution to form a dope of the polyaryl ether sulfone;the polyaryl ether sulfone dope is extruded to form a fiber or film and, then;both sides of the fiber or film are contacted with a liquid miscible with the mixed solvent but incapable of dissolving the polyaryl ether sulfone to remove substantially all the mixed solvent from the fiber or film.

Abstract: Continuous film production from a high pressure feed stream is achieved in a system which provides methods and means for maintaining pressurized gas in an extrusion zone wherein the extrudate may be cooled to form a solid polymeric film. The product film is withdrawn from the extrusion zone continuously through a standing liquid column in fluid communication with the extrusion zone. The film is passed downwardly into a liquid leg below the extrusion zone and upwardly through the liquid column, which has an upper exit end elevated above the pressurized zone thereby exerting super-atmospheric pressure. The product is recovered from the liquid sealing medium, advantageously water, at ambient pressure. Hot aqueous solutions of polyacrylonitrile may be extruded at elevated pressure onto a cooled casting drum in a gaseous environment wherein flashing of the hot solvent is prevented.

Abstract: By expanding a plastic pipe while it is still hot and expandable and thereafter shrinking the so-expanded pipe to a defined point of shrinkage where the pipe is cooled, e.g., by a water spray, it is possible to produce pipes of any diameter within a range using only one extruder die orifice. The expansion and shrinking is carried out using a double cone external mandrel. The process of the invention has the advantage of allowing the production of plastic pipe of any diameter specified by a customer without having to change the die orifice of the extruder.

Abstract: A molten thermoplastic resin is extruded in the form of a double-layer cylindrical hollow film with the two film layers being interconnected with each other by a number of spaced legs and is then immediately passed through an annular gap defined by annular side walls of inner and outer vessels in such a manner that the two film layers are in contact with the respective side walls defining the gap. Coolant is supplied to the inner and outer vessels and overflows above the side walls to bring the coolant into contact with the resin. The level of the coolant overflowing above both side walls is adjusted to be equal and also to have a liquid pressure on the extruded resin balanced with a gas pressure supplied in between the two film layers and the legs of the extruded resin.

Abstract: A semipermeable membrane made of a polyaryl ether sulfone comprised of recurring units represented by the general formula (I): ##STR1## wherein X, X', X" and X"' are non-dissociative substituents, and l, m, n and o are integers of from 0 to 4. The membrane, which is composed of a single continuous polymer phase, has pores of a diameter increasing progressively and continuously from the surface layers to the center portion thereof.The membrane is prepared by the process wherein:the polyaryl ether sulfone is dissolved in a mixed solution to form a dope of the polyaryl ether sulfone;the polyaryl ether sulfone dope is extruded to form a fiber or film and, then;both sides of the fiber or film are contacted with a liquid miscible with the mixed solvent but incapable of dissolving the polyaryl ether sulfone to remove substantially all the mixed solvent from the fiber or film.

Abstract: An extrusion system for the production of foam boards, billets and the like products includes an extruder (20) at a first higher elevation (22) extruding foamable resin through a die in the upper end of an elongated vacuum chamber in the form of an inclined barometric leg (26) which extends at its lower end into a shallow but large surface area pool (39) of liquid such as water. An elongated shroud or hood (44) on the lower end of the leg reduces the pressure head of water above the foam product as it exits the leg and moves out of the pool for processing at a lower second elevation. The large area of the pool reduces its depth for a given volume and minimizes fluctuations in the level of the pool and the pressure head above the product when the vacuum changes. In one embodiment the pool extends beneath substantially the entire floor of the building (30) enclosing the second lower elevation (31) in which the subsequent processing occurs.

Abstract: Organic foams having a low density and very small cell size and method for roducing same in either a metal-loaded or unloaded (nonmetal loaded) form are described. Metal-doped foams are produced by soaking a polymer gel in an aqueous solution of desired metal salt, soaking the gel successively in a solvent series of decreasing polarity to remove water from the gel and replace it with a solvent of lower polarity with each successive solvent in the series being miscible with the solvents on each side and being saturated with the desired metal salt, and removing the last of the solvents from the gel to produce the desired metal-doped foam having desired density cell size, and metal loading. The unloaded or metal-doped foams can be utilized in a variety of applications requiring low density, small cell size foam. For example, rubidium-doped foam made in accordance with the invention has utility in special applications, such as in x-ray lasers.

Abstract: Method and apparatus for processing extruded thermoplastic material for use in siding by advancing the extrudate from the die member through a series of baths which size and shape the extrudate. The process sizes and cools the extrudate, and, thence, heat treats the extrudate followed by a final quenching of the extrudate in its final shape and size.

Abstract: A method of making elongated members of thermoplastic material which simulate natural bamboo by continuously extruding the material through a die, cooling the extruded material downstream of the die, gripping the cool material and transporting the material away from the die and slowing the speed of transport relative to the speed of extrusion at predetermined lengths of extrusion to produce regions of greater external cross-sectional dimensions to provide axially spaced nodes similar to those of bamboo.

Abstract: A metallic substrate and a thermoplastic resinous coating are bonded to one another by a resinous hot melt adhesive. The method of applying the coating to effect the bond includes applying to the metallic substrate a resinous hot melt polyamide adhesive composition which has been found to adhere firmly to the metallic substrate and to form a secure bond with the molten thermoplastic resin extruded onto said hot melt adhesive at high rates of speed.

Abstract: Semi-crystalline polyester/low viscosity polyethylene melt blends, which are non-tacky and non-blocking and are more readily grindable by cryogenic grinding techniques, for providing powders suitable for powder adhesives particularly useful for fusible interlinings or for providing powder coating materials.

Abstract: A foam extrusion apparatus and method employs tandem extruders mounted on horizontal rails for movement toward and away from the end of a vacuum chamber which is in the form of an elongated inclined barometric leg. The upper end of the chamber is closed by a substantial bulkhead also supported on rails and held in inclined position to close the end of the chamber when moved thereagainst. A die is positioned on the inside of the bulkhead and aligned with the leg when closed. The extruders are connected to the die through a length of pipe supported through the bulkhead by a stainless steel bellows. The pipe externally of the bulkhead is provided with a circulating jacket for temperature control. The die is adjustable externally of the bulkhead. The extruders, die and bulkhead are movable as a unit or separately toward and away from the chamber to provide access to the die and the interior of the chamber.

Abstract: Substantial and commercially important increases in polypropylene film production rates without adversely affecting film quality are obtained in a tubular water film process. The improvements comprise modifications in the die lip, in the mandrel air (fluid) slot affecting the cooling gas velocity, and in the upper bubble pressure control. The improvements are especially useful to obtain mill rolls 60 to 80 inches wide.

Abstract: A foam extrusion apparatus and method employs an extruder on an upper level extruding foamable extrudate into the upper end of a large elongated barometric leg which extends at a relatively shallow angle into a pool of water at a lower level. A conveyor in the barometric leg extends through a large radius in the pool to guide the extrudate from the pool for further processing. The leg is in the form of an elongated pipeline fabricated from sections and supported on an inclined ramp. Some of the sections are securely anchored to the ramp to resist axial forces when the leg is evacuated. The sections may be reinforced concrete or fabricated reinforced steel of a variety of sectional shapes. Each section is sealed end-to-end so that a vacuum within the leg will draw water from the pool into the leg leaving a vacuum chamber at the upper end of the leg in which the extrudate expands.

Abstract: Process for the extrusion, followed by cooling with water, of compositions based on alpha-olefin polymers. The composition being extruded comprises a phenolic anti-oxidizing agent, an organic phosphite, and a carbonate of an alkaline-earth metal. The process permits fabricating films, filaments and tubes.

Abstract: An in-line method of forming a laminate of a heat sensitive foam sheet material, and a hot extruded polymeric product comprising hot extruding a polymeric material into a shaped product and while still hot contacting the shaped product with a face of the heat sensitive foam sheet material and thereafter cooling the resulting product. Such face is previously coated with a layer of a heat sealing substance which is activated at a temperature below the softening point of the heat sensitive foam sheet. The heat seal contact takes place under minimal pressure when the surface temperature of the shaped product is still high enough to activate the heat sealing substance but not high enough to damage the heat sensitive sheet. The laminates so made are part of the invention.

Abstract: A vinylidene chloride copolymer film having excellent bubble stability in an inflation-stretching process and excellent cold resistance is prepared by inflation-stretching a tubular amorphous substance obtained by melt-extruding and quenching a composition comprising vinylidene chloride copolymer, a miscible type elastomer (A component) and a particle dispersion type elastomer (B component) in a range surrounded by the lines (a), (b), (c) and (d) ##EQU1## WHEREIN A WEIGHT PERCENT OF THE B component to total elastomers is plotted on X axis (abscissa) and a weight percent of total content of the A component and the B component to total components is plotted on Y axis (ordinate).

Abstract: A process for producing a plastic pipe having an oval cross-sectional shape with a high dimensional precision, which comprises conducting a roughly shaped plastic pipe having an oval cross-sectional shape, which is in the softened state and composed of a large-diameter portion, a small-diameter portion and transitional portions connecting them to each other, to a cooling tank while its shape is adjusted by being passed through a forming tube with its large-diameter portion down; cooling the form-adjusted plastic pipe in the cooling tank by dipping the large-diameter portion or both the large diameter portion and a part of the transitional portions contiguous thereto in a cooling bath; and subjecting that portion of the form-adjusted plastic pipe which is out of the cooling bath to a shower of a cooling liquid. This plastic pipe is useful for a drainage or sewage system.

Abstract: Semi-crystalline polyester/low viscosity polyethylene melt blends, which are non-tacky and non-blocking and are more readily grindable by cryogenic grinding techniques, for providing powders suitable for powder adhesives particularly useful for fusible interlinings or for providing powder coating materials; and to the process for making the powder.

Abstract: Tubular film-forming system in which a tubular extrudate is rapidly cooled and the cooled tube is withdrawn by engagement with a movable fluid-shedding surface which firmly grips the tube without damaging the surface thereof. The system is particularly suitable for gripping a tube the surface of which is moistened by liquid from an annular cooling bath.

Abstract: Cooling a tubular extrudate for conversion to tubular film by passing the extrudate through a bath of cooling liquid so that the external surface of the extrudate contacts in sequence countercurrent streams of cooling liquid in a quiescent zone, a restricted throttle zone and a spiral flow zone.

Abstract: Method and apparatus for processing extruded thermoplastic material for use in siding by advancing the extrudate from the die member through a series of baths which size and shape the extrudate. The process sizes and cools the extrudate, and, thence, heat treats the extrudate followed by a final quenching of the extrudate in its final shape and size.

Abstract: Films are formed from liquid polymeric material passed through an elongate exit slit of a die and drawn to a solidification region. A condition of flow of liquid through the slit is established to enforce a controlled ratio of extensional strain rate to shear strain rate on the material leaving the slit by providing a predetermined slit profile to maintain that ratio above a minimum throughout the width of the film.

Abstract: Process for cooling a freshly extruded, incompletely solidified foil of a thermoplastic polymer by extruding said foil into a liquid cooling bath and directing against said foil below the bath surface along a line extending the entire width of said foil at least one narrow, unbroken stream of cooling liquid. The stream(s) respectively are directed angularly against a side of said foil at right angles thereto or in a direction opposite to the direction of movement of said foil into said bath, i.e., at an angle between 0.degree. and 60.degree. relative to a plane which is normal to said foil. The apparatus embodies an extrusion nozzle for extruding the foil downwardly into a body of cooling liquid in a tank directly below said nozzle. One or more tubes are normally immersed in said body of liquid and extend longitudinally parallel to and in juxtaposition to the foil entering said body of cooling liquid and also parallel to the upper surface of the cooling liquid.

Abstract: A method of removing an article from a chamber having a reduced pressure therein by connecting the chamber to a pool of liquid by a barometric leg is disclosed. The method provides a conveyor in said barometric leg and allows said article to float up into engagement with said conveyor so that the force exerted on the article by the conveyor moves the article down into the pool of liquid and out into the atmosphere.

Abstract: This invention relates to film- and fiber-forming polyhydrazide solutions (dopes) in a solvent system comprising concentrated sulfuric acid or mixtures thereof with fluorosulfonic acid. Some dopes of this invention are optically anisotropic.

Abstract: A method for producing arcuately curved film casings particularly suitable for a foodstuff such as meat or the like, by an inflation process, wherein a non-stretched resin tube is advanced along and in contact with a circumferential surface of a cylindrical shaping member at the time of inflation of the tube.

Abstract: A sheet film is produced from a tubular thermoplastic resin film by cooling a molten tubular film of crystalline thermoplastic resin, for example, polypropylene, extruded downward from an annular die in direct contact simultaneously with cooling liquids on the outside and inside of the film, the cooling liquid on the outside being in an outside cooling liquid tank and in contact with the outside of the film and the cooling liquid on the inside flowing down along the surface of a mandrel provided through the outside cooling liquid tank and in contact with the inside of the film, a liquid level of the cooling liquid on the inside being kept higher by 5-15 mm than that of the cooling liquid on the outside; cutting open length wise one or two side ends of the film just before being flattened and folded by nip rolls thereby to discharge the cooling liquid from the inside; and removing the liquid attached to the surfaces of the resulting sheet films withdrawn by the nip rolls promptly.

Abstract: Cooling an extruding thermoplastic tube by feeding the tube adjacent a cooling surface, maintaining a sheath of heat-transfer fluid between the tube and surface and preferentially cooling at least a selected area of the tube by transversely displacing the tube to decrease the thickness of the sheath between the selected area and the cooling surface. The invention is particularly suitable, for the production of thermoplastic films by orienting a cast tubular extrudate which has been cooled by means of an internal mandrel.

Abstract: A process for preparing a shaped article by melt-extruding a polyester containing tetramethylene naphthalene-2,6-dicarboxylate or hexamethylene naphthalene-2,6-dicarboxylate as a main recurring unit, wherein the extrudate is exposed to a temperature of 75.degree. to 450.degree.C. for 1 to 180 seconds immediately after extrusion.

Abstract: Disclosed is a process for fabrication of elastomer or plastomer tubes from sensitized aqueous dispersions wherein the tube is extruded through a shaping apparatus. Heated air is discharged into the tube as it is extruded, with the heated air flowing axially through the tube to vaporize and remove serum exuded into the tube as the gelling process continues. The tube, having the heated air flowing therethrough may be passed through a washing vat to remove serum from its external surface.

Abstract: A method for shaping a tubular film in a downward and wet manner is provided in which an extruded tubular film is coagulated in contact with a coagulation liquid which flows down along the inside surface of a cylindrical composite perforated wall composed of a cylindrical perforated wall and cylindrically piled up circular rings of coiled wire provided in a single layer and in contact with the inner surface of said cylindrical perforated wall, provided in a negative pressure chamber connected to the lower part of a coagulation liquid-supplying pool; in this coagulation, coagulation liquid is fully utilized by mixing with a reflux coagulation liquid formed when a part of coagulation liquid once flows out through said wall and is collected in a plurality of coagulation liquid-collecting weirs provided around the outer surface of said wall, and then flows again through said wall to the inside thereof; and said film is drawn downward while being supported on the inner surface of said wall by friction due to sucti

Abstract: A metallic substrate, such illustratively as wire, to which is bonded by means of a resinous hot melt adhesive and in a continuous operation a thermoplastic resinous coating. The method of making the coated metallic substrate comprises applying a resinous hot melt adhesive about the metallic substrate and thereafter extruding a molten thermoplastic resin onto the deposited adhesive at high rates of speed.

Abstract: The invention relates to threads, fibers or films comprising polyvinylidene fluoride, with good dye affinity for plastosoluble and cationic dyestuffs.More particularly, the invention relates to threads, fibers or films formed of a mixture of vinylidene fluoride homopolymer and of a copolymer containing at least 60% by weight of methyl methacrylate units and 5 to 40% by weight of units of at least one acid ethylenic comonomer, copolymerizable with methyl methacrylate.The threads and fibers in accordance with the invention can be used in particular in the field of textiles.