Abstract: Fiber reinforced thermoplastic parts having good surface characteristics are produced by a process involving: preheating fiber reinforced composite to achieve at least a flowable viscosity of the polymer, and (2) molding under controlled rheological conditions. The preheating is conducted on composites that are predominantly amorphous thermoplastic polymers, copolymers, polyblends or alloys reinforced with continuous glass fiber strand reinforcing mat. The amount of the mat present in the laminate is less than around 40 weight percent of the composite. The temperature of preheating is at least greater than the glass transition temperature of the polymer and less than the degradation temperature of the polymer to expand the composite.

Abstract: Cylindrical carbon blanks are assembled into one or more upright stacks which are advanced stepwise in an upward direction in one or more upright tubes which insulate the column or columns from the surrounding atmosphere. The blanks in the upright tube or tubes are preheated by exchanging heat with an inert gas, such as pure argon, and the preheated blanks are thereupon conveyed along one or more horizontal path sections into the upper end of an additional tube wherein the blanks are heated to graphitizing temperature by a series of electrode pairs. The thus obtained graphite electrodes are cooled by inert gas which is thereupon admitted into the upright tube or tubes to preheat fresh carbon blanks.

Abstract: An apparatus and a method of making brake pads (60) having the step of heat preforming a plurality of dosages (39) of a friction material for brake pads (60) to obtain a plurality of blanks (61) on which respective metal holders (53) are then placed, and the step of hot molding, individually and simultaneously, such blanks (61) to form a plurality of brake pads (60).

Abstract: A reverse osmosis water purification module has an enclosed cylindrical housing in which at least twelve purification elements are mounted in a uniform, spaced parallel fashion. Each element consists of a long flat member having a thermoplastic sheet backing formed into a slightly curved cross section and having a semi-permeable membrane disposed thereon. The backing has three-dimensional porosity for purified water such that water passing through the membrane portion of the element travels along the backing member to an end. The ends of the module are mounted in a collection manifold which is sealed off from the remainder of the housing interior. A method of manufacturing the elements continuously is also provided wherein a continuous length of flexible backing material is fed sequentially through a heater, a forming die to impart a curved cross-section to the backing material, an extruder wherein membrane forming fluid is extruded around the periphery of the backing, a chill bath and a heating bath.

Abstract: A plastic tube is sealed at its end by placing the tube in a pair of spaced apart tube holders having tube receiving pockets. The tube is cut by a cutting device movable into and out of the space between the pockets to form two distinct tube sections which are melted at their ends while in the clamped condition. The cut ends are then brought into contact with each other in a mis-aligned condition offset by one-half the thickness of a tube wall to seal the tube end.

Abstract: In a known process of making biaxially oriented polyethylene terephthalate photographic film, a certain amount of curl in the longitudinal direction can be imparted to the film by carrying out the longitudinal stretching step of that process while the film is asymmetrically heated across its thickness to a temperature gradient Delta T across the film of at least 10.degree. C. while the longitudinal stretching tension applied to the film is less than 10 N/sq.mm.

Abstract: Polymerized foam material in flat billet form is enclosed in a heat-retaining envelope and heated to forming temperature then promptly loaded into an innovative unheated forming press and accurately formed before cooling below forming temperature. The heat-retaining envelope has an expansive skin on one side and a contractive skin on the other side to facilitate bending without wrinkling or other distortion. The forming press utilizes a rigid male form punch and a spring-tensioned elastic belt, supported on a pair of variably-spaced rollers, initially presenting a flat compliant surface upon which the heated workpiece is placed. Pressure from the form punch progressively deflects the workpiece and the belt, which becomes a compliant mold member conforming itself and the workpiece progressively around the form punch to yield an article of required carved shape, free of wrinkles or tool creep distortions.

Abstract: A method of shaping a soap bar comprising the steps of obtaining a soap bar, placing the bar in a microwave oven, energizing the oven with sufficient power and time to soften the bar, and forming the softened bar into a desired shape and size.

Abstract: Pellets of polymeric material are fed into the hopper of a screw extruder to produce a molten extrudate, and a liquid additive, particularly a molten lubricant, is introduced downstream of the hopper into the root of a screw flight, particularly in the feed section of the screw longitudinally and internally of the screw shaft.

Abstract: A molding process of a molding compound containing an ingredient such as a binder, e.g., pitch or a thermosetting resin which generate gas before being set, is disclosed, wherein the molding compound is heated and molded under pressure according to a special temperature pattern. First, the molding compound may be preheated substantially uniformly to a temperature at which the binder melts and generates reaction gas. Next, temperature gradient in the direction of thickness of the molding is created while raising the temperature of the molding to an upper limit temperature so that the setting of the molding progressively advances from the higher temperature to the lower temperature side of the molding.

Abstract: Method for manufacturing a molded article, for use, for example as a fluid filter or as a preform for a structural composite, is prepared from a batt of nonwoven structural fibers and a binder material, such as binder fibers or a thermoresponsive resin. The batt is stabilized by exposing it to a temperature slightly below the melting point of the binder material, so that the binder material becomes tacky and bonds the fiber materials at the surface of the batt. By exposing the batt to the heat for only a few seconds, only the binder material at the surface of the batt bonds the structural fibers; the structural fibers within the batt remain unbonded. Accordingly, the batt is "skinned", so that it is stiff enough to be handled, but is still flexible enough that it can be molded into complex shapes. The molding is effected in a mold in which heated air is drawn through the batt to force it to assume the contours of the mold.

Abstract: A process for continuous fabrication of thermoplastic webs from at least one extruded thermoplastic web heated to processing temperature. This thermoplastic web is cooled under the application of area pressure down to a temperature at which smoothing of the surface is terminated. A calibrating and smoothing mechanism in the device for performing the process according to the invention consists of a double-band press which includes an apparatus for conducting heat away from the thermoplastic web in the reaction zone in which the area pressure is applied.

Abstract: A method of molding oriented structural yarn/polymer matrix composite structural articles in which a preform of oriented yarn layers saturated with a resin is placed in a shape-defining mold, which is put in an enclosure, and subjected to heat and pressure to cure the resin, after which a cooling medium may be introduced. To enable the use of lightweight multi-part molds, and a mixture of pressure is distributed evenly, an internal liner is collapsed about the mold prior to curing. The process is extremely productive, and allows for accuracy and reproducibility through the use of real time temperature monitoring and closed loop feedback control.

Abstract: In a method and apparatus for continuous shaping of carbon-fiber-reinforced plastic tubes, a carbon fiber prepreg in tape form impregnated with a first thermosetting resin is laminated on and around a mandrel; the laminate provided on said mandrel is preheated; and the preheated laminate is pulled in and through a hot die together with the mandrel, during which it is gelled, cured, and shaped into a carbon-fiber-reinforced plastic tube, wherein a second thermosetting resin is uniformly supplied onto the outer circumference of the laminate in a resin squeezing zone in the hot die.

Abstract: A process for producing molded articles, especially molded polyurethane foam articles, wherein the mold is treated with an aqueous release agent or a concentrate of one or more release-active substances in organic solvent. The release agent is preheated, e.g. by an atomizer supplied with hot pressurized air, prior to being applied to the mold. The process enables the efficient use of water-base release agents and thus reduces the emission of harmful organic solvents into the atmosphere.

Abstract: An apparatus for heat staking plastic parts to other parts to form an assembly are featured, using multiple heating elements which are arranged in zones and which are separately programmable in terms of temperature and displacement to develop optimum deformation of plastic having different characteristics. The heating elements are isolated thermally to provide an improved conservation of heat energy.

Abstract: The invention comprises a method and apparatus wherein an insert, preferably made of plastic and preferably allowing a melt-on bonding with the tubes and whose floor has a traversing opening for each tube, is inserted into the first part of the injection mold (top mold or bottom mold) as a positioning element for the tubes in such a manner that the insert is at least partially locked or secured into the first part of the injection mold. A tube is then placed in each opening of the insert. A mandrel is then placed in each tube, whereupon the injection mold is locked in such a manner that, if necessary, the mandrels are locked into the second part of the injection mold (bottom mold or top mold). A molten thermoplastic material is then injected, via a sprue provided in the injection mold, into a cavity formed by the injection mold, the insert and the tube ends.

Abstract: A process for producing a surface-embossed, deep-drawn article suitable for an interior finish or lining of a motor vehicle, for example, starts with a partially-crystalline polymeric material, i.e., one having crystallites, in film form. The film-form material is heated to a temperature below the melting point of its crystallites an surface embossed. The embossed material is then cooled and crosslinked. The crosslinking is preferably done by irradiating the cooled material with a high-energy beam such as an accelerated electron beam, for example. The cooled and crosslinked material is then reheated, this time to a temperature above the melting point of its crystallites, and deep drawn into the shape of the article.

Abstract: A foam of cross-linked polyethylene having microcell structure is prepared using a chemical cross-linking initiator having a 10 hours half life temperature of from 80.degree. to 110.degree. C. In a preferred embodiment, the chemical cross-linking agent is employed in combination with co-cross-linking agent such as triallyl cyanurate.

Abstract: A method for bonding silicone rubber to a metal member is shown in which the metal member is first treated by heating the metal member to a temperature and for a time sufficient to form an oxide layer on the outer surface of the metal member. The treated metal member is then contacted with an uncured silicone rubber composition, and the silicone rubber composition is cured to bond the treated metal member to the silicone rubber composition.

Abstract: A method of forming a windowed unitary panel having a peripheral edge portion of a windowpane of glazing integrally embedded within a frame of high modulus plastic material includes heating the pane to a preselected temperature prior to its being positioned within a mold. The peripheral edge portion of the windowpane protrudes into the mold cavity so that the high modulus plastic material forming the frame encapsulates the peripheral edge portion. This prevents buckling of the windowpane since the preheated windowpane contracts simultaneously with the contraction of the rigid frame as it cools from the molding temperature to ambient.

Abstract: A molding process for producing a molded plastic product with a resin coating layer formed on its surface, which comprises electrostatically coating a powdery resin composition on the inner surface of a mold, filling and molding a plastic material in the mold to form a molded plastic product, and plasticizing, under compression, said powdery resin composition by the heat of the filled plastic material and/or by the heat for molding the filled plastic material, to form a resin coating layer securely bonded to the surface of the molded plastic product by anchor effect.

Abstract: Gaskets are formed in container closures fabricated from polyolefin resins exhibiting substantially no response to heat activation by radio frequency electrical energy by introducing a vinyl chloride plastisol containing a vinyl chloride polymer resin and a plasticizer having a loss factor in the range of 0.1-12 into the closure. The closure is preheated to 55.degree. to 100.degree. C. by conventional means and then the plastisol is fused in the closure by exposure to a field of radio frequency electrical energy.

Abstract: A method and an apparatus for continuous shaping of carbon-fiber-reinforced plastic tubes, wherein a carbon fiber prepreg in tape form impregnated with a thermosetting resin is laminated on and around a mandrel, then the laminated carbon fiber prepreg tape on the mandrel is preheated, and the thus preheated laminate is pulled in and through a hot die together with the mandrel so as to subject the carbon fiber prepreg to gelling, curing and shaping into a predetermined carbon-fiber-reinforced plastic tube, the pulling operations being continuously carried out by alternate motion of first and second grasping mechanism in such a manner that the pulling force is generated in the second grasping mechanism, while the first grasping mechanism still retains its pulling force, and finally the gellation of the laminate is completed at the first half part of the hot die.

Abstract: In a process for producing a formed article of aromatic polyamide-imide resin by compression-molding at the temperature lower than the melting temperature of the resin, the improvement which comprises subjecting the resin, prior to the molding, to heat treatment in an oxygen-containing gas under conditions satisfying the following equationlogt.gtoreq.a.sub.1 +a.sub.2 T+a.sub.3 T.sup.2 +a.sub.4 T.sup.3,wherein a.sub.1 =2.5841, a.sub.2 =-8.4926.times.10.sup.-3, a.sub.3 =6.9984.times.10.sup.-6, and a.sub.4 =-2.0449.times.10.sup.-8 ; t and T represent the heat-treatment time in hour and the heat-treatment temperature in .degree.C., respectively; and 200.degree. C..ltoreq.T.ltoreq.400.degree.C.

Abstract: A mold for use in heat expanding prefoamed polystyrene beads to form a part of a predetermined shape is disclosed. The mold comprises a cavity defined by separable mold wall portions. Each mold wall portion has on its exterior a chamber into which a heating medium is introduced to heat the mold walls and also into which cooling medium is introduced to cool the walls. A plurality of nozzles are provided in the mold walls and a corresponding plurality of tubes interconnect the nozzles to a manifold located in the corresponding chamber. A pressurized heating medium is introduced to the manifold whereby the heating medium is injected into the cavity to expand prefoamed polystyrene beads in the cavity. A device is provided on the manifold for the selective removal of condensate from the manifold. The mold construction provides for an economical, readily manufactured unit.

Abstract: There is described a process for the production of high temperature resistant, high density ceramic molded articles at a temperature above 1300.degree. C. and at high pressure in a mold. For this purpose, the blank is heated outside the mold, transferred with a die at 1 to 10 m/sec into the cold mold, compressed there and ejected in the pressing direction. Thereby, the residence time in the mold must be less than 3 msec and the sum of the transport time of the blank from heating up to the mold and the residence time in the mold so regulated that the temperature drop between the nucleus of the blank and the surface of the blank does not exceed 150.degree. C.

Abstract: Wire which has been coated with a polymeric material is useful in a wide variety of applications. One such application is as a winding for electrical equipment such as motors, transformers, magnetic coils, relays and the like. Generally, coated wires of this type have been prepared by coating the wire with multiple layers of a solution of the coating material. It has been determined that metal wires can be satisfactorily coated with a specific type of thermoplastic composition in a single layer without using solvents. This process utilizes a tubing type cross-head die with the thermoplastic composition comprising a mixture of 80% to 99% by weight polyethylene terephthalate and from 1% to 20% by weight of polyethylene, polypropylene, or a mixture thereof.

Abstract: A reinforced thermosetting polymer, in a pasty state, is molded under conditions of internal heating of the material and dielectric losses with high frequency and external heating using the mold elements.

Abstract: In a method of producing an extruded, cross-linked cable coating of filled polyethylene wherein the extruder is charged with commingled polyethylene pellets and filler-EPR masterbatch pellets containing a peroxide cross-linking agent, the peroxide is incorporated in the masterbatch pellets by application to and absorption in the pellets during advance of the pellets to the extruder, while the pellets are continuously maintained at an elevated temperature for preventing bleed-out of absorbed peroxide.

Abstract: A method for stabilizing the Tmc of PPS subjected to heat treatment in a temperature range between 240.degree. C. and 320.degree. C., particularly during the heating process of an extrusion operation, by increasing the tmperature of the polymer through the 240.degree. C.-320.degree. C. range at a rate of at least 20.degree. C. per minute or by subsequently raising the temperature of the polymer to at least 350.degree. C. for a time sufficient to stabilize the Tmc of the polymer.

Abstract: In order to control the fusion of a polyvinyl chloride plastic material which is being moved along a screw of an extruder from a feed section (36) through a compression section (37) to a metering section (39) and crosshead (26), the melt pressure is measured in the compression section. The melt pressure, which is indicative of the fusion qualities of the plastic material, is used to control the temperature of the plastic material in the feed section to cause it to be substantially homogenous at the crosshead.

Abstract: A process for preparing a thermoplastic poly(imidesulfone) is disclosed. This resulting material has thermoplastic properties which are generally associated with polysulfones but not polyimides, and solvent resistant which is generally associated with polyimides but not polysulfones. This system is processable in the 250.degree.-350.degree. C. range for molding, adhesive and laminating applications. This unique thermoplastic poly(imidesulfone) is obtained by incorporating an aromatic sulfone moiety into the backbone of an aromatic linear polyimide by dissolving a quantity of a 3,3',4,4'-benzophenonetetracarboxylic dianhydride (BTDA) in a solution of 3,3'-diaminodiphenylsulfone and bis(2-methoxyethyl)ether, precipitating the reactant product in water, filtering and drying the recovered poly(amide-acid sulfone) and converting it to the poly(imidesulfone) by heating.

Abstract: An extruder for polymeric materials, comprising a housing forming a mastication stage with one or more feedscrews, includes a preheating and premixing stage with a cylindrical chamber centered on a vertical axis which is eccentrically traversed by a supply passage for the feeding of polymeric material to the mastication stage. The chamber, which is heated from the outside, contains two mixing wheels jointly rotatable about the axis, each wheel having a plurality of raker arms projecting from a hub to the chamber periphery in an off-radial direction and with a tilt causing the arms of the upper wheel to draw incoming fresh material toward the axis and down into the orbit of the arms of the lower wheels which in turn drive the material toward the periphery and, to the extent that an outlet port leading to the mastication stage is obstructed, back into the orbit of the arms of the upper wheel for recirculation.

Abstract: A method of thermoforming comprising providing a continuous sheet of thermoplastic polymeric foam, transporting said sheet through an atmosphere of at least predominantly steam at a temperature of at least 215.degree. F. maintaining said sheet in said atmosphere for a time sufficient to cause a decrease in the density thereof; thereafter while under the influence of said temperature, deforming at least a portion of said sheet to a predetermined shape and while so deformed, cooling the same to cause retention of said shape and a system for carrying out said method.

Abstract: A process of extrusion molding plasticized vulcanizable or cross-linkable rubber or synthetic resin materials, comprising the steps of heating said materials to an elevated temperature in a short time immediately before a molding die and vulcanizing or cross-linking the materials in the manner of maintaining said elevated temperature substantially while the materials are passing through the die or for a while after they have passed through the die, thereby obtaining mold goods.

Abstract: A method of producing a biaxially oriented sheet or film, wherein molten resin is simultaneously, biaxially oriented in a direction of extruding the molten resin and in a direction perpendicular thereto, and an apparatus therefor, are disclosed. In the method of producing a biaxially oriented sheet or film, the molten resin is extruded into a tubular form in the horizontal direction, once cooled, thereafter, in heating the tubular resin prior to the biaxial orientation, the tubular resin is uniformly heated with the heating applied on the vertically lower side and the heating applied on the vertically upper side of the tubular resin being controlled separately of each other so as to prevent the ununiformity of the heating of the tubular resin in the circumferential direction thereof due to the elevation in heat caused by a thermal convection phenomenon, and then, the tubular resin is biaxially oriented.

Abstract: In order to increase the stability of a device comprising at least one electrode and a conductive polymer composition in contact therewith, the contact resistance between the electrode and the composition should be reduced. This can be achieved by contacting the molten polymer composition with the electrode while the electrode is at a temperature above the melting point of the composition. Preferably, the polymer composition is melt-extruded over the electrode or electrodes, as for example when extruding the composition over a pair of pre-heated stranded wires.

Abstract: An extruder for thermoplastic or elastomeric materials has a mastication stage with one or more feedscrews preceded by a preheating zone in which the incoming bulk material is circulated and possibly recirculated by two screw-type conveyor members or augers in a loop within a heated extension of the extruder housing. The augers may be counterrotatingly disposed in two juxtaposed cylindrical compartments or may be coaxially nested and corotating with opposite pitch.

Abstract: Novel resin products produced by reacting unique polycyclic, aromatic, polycarboxylic acid products with low molecular weight polyols display satisfactory toughness properties and good Barcol hardness values. The process for preparing these novel resin products first involves preparing an intimate, finely divided mixture comprising the acid product derived from the nitric acid oxidation of naturally occurring solid carbonaceous material, a roughly equivalent amount of a liquid polyol, and a suitable acid catalyst. The mixture is then subjected to a precure step which involves heating at temperatures between 80.degree. and 150.degree. C. for from about fifteen minutes to about four hours. The precured mixture may thereafter be subjected to suitable molding conditions at a temperature below about 220.degree. C.

Abstract: A method of forming a reinforced foam structure or laminate wherein a low density, fast reacting liquid foamable resin is sprayed under pressure into a low density fiberglass mat to penetrate and wet the fibers. The foam then expands within the fiberglass mat, forming a low density foam sheet having fiberglass distributed substantially continuously therethrough. A support or cover sheet is preferably laminated to the foam-fiberglass sheet and the laminate is formed under heat and pressure in a die into a contoured shape, simultaneously curing the resin foam.

Abstract: In injection molding thermoplastic resin compositions containing reinforcing materials and/or fillers, high quality molded articles superior in surface gloss and exhibiting substantially no surface defect can be obtained, by employing a technical measure, in which only superficial layer of the inner wall surface of the mold is selectively heated, by high-frequency induction heating, to a temperature above the heat distortion temperature of the thermoplastic resin composition employed prior to injection molding and cooling and solidifying the resin.

Abstract: A discrete thermoplastic composition is formed into a shaped article in a rapid stamping process. The composition is placed on and preheated with a rigid metal plate which has been preshaped to fit the contour of one of the dies of the stamping press. The heated composition and metal plate are then transferred to the stamping press where the composition is stamped and cooled into a three-dimensional shaped object. The surface of the metal plate contacting the composition has a special finish so that desired surface effects can be produced on the stamped article.

Abstract: A process for producing articles of ultra high molecular weight high density polyethylene is disclosed which avoids long heating and cooling cycles, and compacting pressures in the order of 3,000 to 4,000 lbs/sq. inch. The resin is intensively mixed and thermokinetically heated in an enclosed container with a plurality of blades attached to arms rotating about an axis with a blade tip speed of at least 18 m/sec. until the resin reaches a desired discharge temperature of at least 135.degree. C. After being discharged from the mixing step, the ultra high molecular weight resin is formed into the desired shape within a time such that degradation does not occur.

Abstract: A molding process for compression molding blanks from a polymerizable, thermosetting resinous composition in which pearlescent particulate materials are mixed: Upper and lower mold parts, at least one of which has mold cavities formed in it, are held in an open condition. The resinous composition is sandwiched between two sheets of a film material and is placed on the lower mold part. At least one of the layers of film material is stretchable. The mold parts are moved together until the upper mold part contacts, without applying pressure to, the top of the resinous composition. The mold parts are held at this semi-closed condition for a period of time at an elevated temperature, thereby causing the viscosity of the resinous composition to rise significantly. The mold parts are then moved to the fully closed condition at which molding pressure is applied to the resinous material, and the resinous composition is then forced into and shaped by the mold cavities in the mold parts.

Abstract: Granular material, gaseous fuel and air are preheated to just below the sintering temperature of the granular material. The hot granular material is passed through a mold in which a reticular device for distributing the fuel is provided to define a conical or vaulted surface with its vertex upstream, extending across the cross-section of the mold and defining the upstream end of a combustion zone into which the granular material passes after entering the mold. Air is supplied through a perforated wall and pushes the granular material as well as advancing with it to the combustion zone. Combustion of the fuel in the combustion zone thus defined brings the granular material to the sintering temperature and a fused rod of cellular structure (i.e. with small enclosed voids, generally not communicating with each other) is continuously formed that is pulled out by rolls in a pre-cooling section of the apparatus immediately downstream of the mold.

Abstract: This invention substantially improves the surface finish on resin filled foamed molded plastic products manufactured by injection molding by pre-heating the skin surface of that part of the mold in contact with the part prior to the injection cycle of the machine and then subsequently chilling the mold via internal tube connections to shorten the time needed in the manufacturing cycle for solidifying the part sufficiently for release from the mold.

Abstract: The instant invention is directed to a process for the continuous production of block-shaped foam and to the equipment used therefore. The process of the invention broadly involves the heating of the bottom film prior to application of the foamable mixture. In this way, the undesirable crust generally formed on the bottom of the foam blocks is substantially reduced and/or eliminated.

Abstract: A plastics material web produced by extrusion or calendering and having a small thermoforming temperature range is located in two stages; a first stage in which radiant heaters heat the web approximately to thermoforming temperature and a second stage in which the temperature variations in the web due to thickness variations and heating variations are compensated by passing the web round rollers heated to the thermoforming temperature. The heated web is passed step by step to a thermoforming machine which operates cyclically on the web to form articles therein.

Abstract: Foam insulated conductor is produced by heating the conductor to a temperature at which the conductor retains sufficient heat to effect crosslinking and foaming of a polymer composition, followed by extruding the polymer composition onto the conductor, with the crosslinking and foaming being effcted by the retained heat.