Abstract: A method of manufacturing shoe sole material which is lightweight in addition to having such properties as the conventional rubber sole materials have like wear resistance and elasticity etc., in a simple manner by forming the outsole and midsole layers into one piece by fusion using a mold. The mold comprises mold pieces having on their surface optional pattern and protruding stripes of the same or different pattern carved at equal intervals, and permits a streamline-shaped heel-up on the rear end of the portions which are to become heels, at the same time as forming the midsole and outsole layers into one piece by fusion.

Abstract: A substantially water-impermeable polyolefin foam made of expandable polyolefin beads. The polyolefin foam is prepared by a particular process in which after heating expandable polyolefin beads and before cooling the heated beads in a mold, the heated beads were allowed to stand in the state that the polyolefin resin maintains the flowability.

Abstract: A process is described for improving the rate of production, other conditions being equal, of extruded polymer products, containing foaming- and/or cross-linking agents, which particularly resides in using a "melting torpedo" rotatable element in the melting section of the extrusion apparatus.

Abstract: In a process for producing a foamed article of a polyolefin resin which comprises filling in a mold pre-foamed particles of a polyolefin resin containing a gaseous mixture consisting of an inorganic gas and a volatile organic blowing agent in their cells and heating them to mold a foamed article; the improvement wherein the pre-foamed particles of the resin are those in which the total pressure of the gaseous mixture is 1.4 to 2.5 kg/cm.sup.2 (abs.), with the partial pressure of the inorganic gas being maintained at 0.4 to 1.1 kg/cm.sup.2 (abs.) and the partial pressure of the volatile blowing agent at 0.8 to 1.6 kg/cm.sup.2 (abs.).

Abstract: In the manufacture of bodies of foamed plastic material, a polymeric synthetic resin base material is mixed with a cross-linking agent, a foaming agent and at least one further additive. The resulting mixture is shaped without a decomposition of the cross-linking and foaming agent and is subsequently heated to effect cross-linking and foaming. In order to obtain bodies of foamed plastic materials which owing to their high flexibility and low flammability are particularly suitable as heat-insulating materials in buildings, the base material consists only of a chlorinated polyethylene resin or a mixture of such resins and heat-stabilizing agents known for use with halogen-containing polymers are incorporated in the mixture.

Abstract: An improved apparatus for extruding an expandable thermoplastic composition onto an elongated article is disclosed comprising an extruder housing; a cylindrical extruder screw axially positioned within an extruder barrel within the housing; a device for heating the expandable thermoplastic composition passing through the hollow chamber; a gas input for supplying an inert gas into the extruder barrel; and a die head attached to the output end of the extruder housing through which an elongated article is passed for the extrusion thereon of the expandable thermoplastic composition.

Abstract: An expansion-molded product made from expanded cross-linked polyethylene particles each of which has an outer skin and inner cellular core, said outer skin each being fused and welded together to form an interfacial membrane whose average thickness is as thick as at least three times that of a cell membrane of the inner cellular core, is prepared by charging a lot of the particles into a mold, heating the particles therein to such an extent that the space among the particles is filled and then aging thus obtained molded product.The expanded particle each has a structure having an outer skin on an inner cellular core, the outer skin being as thick as at least three times cell membrane of the inner cellular core. The expandable particles are prepared by impregnating a foaming agent into the cross-linked polyethylene particles and heating so that the expandable particles are subjected to a step in which the foaming agent existing in the surface thereof is preferentially forced to evaporate.

Abstract: A method for making reticulated foam structure of a crosslinkable thermosetting polymer which includes the steps of dissolving the polymer in a relatively volatile solvent, forming the resultant solution into an emulsion with a relatively less volatile emulsifying vehicle, forming the emulsion into the desired structure, removing the solvent from the structure, removing the vehicle and curing the structure to form a reticulated foam structure.

Abstract: This application is directed to light-weight and hard foam materials. The foams of this invention are prepared by extruding thermoplastic crystalline plastics in the presence of highly volatile organic liquids as the foaming agents. In accordance with the present method crystalline polyolefins, in the presence of polybutadiene, ethylenevinylacetate copolymers, ethylene-propylenes and/or ethylene-propylene terpolymer rubbers, and optionally radical formers such as suitable peroxides, azidene, sulfonyl azidene or the like, and inhibitors for radical decomposition, such as triallylcyanurate or an acrylate selected from the group consisting of trimethylolpropane-trimethacrylate, allyl-methacrylate, tetrahydrofurfurylmethacrylate, triethyleneglycol-dimethacrylate, polyethyleneglycol-dimethacrylate or the like, are converted into foam-like molded bodies by means of a highly volatile organic liquid foaming agent.

Abstract: A method for manufacturing a low density synthetic resin foamed body is disclosed which is characterized by the steps of filling a mixture of 100 parts by weight of an ethylene-vinyl acetate copolymer, 20-80 parts by weight of a foaming agent, and 1.0-5.0 parts by weight of a crosslinking agent in a mold, closing the mold with a lid, heating the mold to form a foamed body, cooling the foamed body as it is kept in the mold, and opening the lid of the mold.

Abstract: A method for foaming heat foamable thermoplastic resin preforms and the product produced thereby. Said preforms are foamed in a series of foaming stages, said series comprising at least one stress-relieving foaming stage and at least one additional foaming stage subsequent thereto and at a higher temperature. This method facilitates the production of foam sheets, slabs and planks of better quality than that provided by previously known single stage foaming methods. In an example, a crosslinked, expandable, polyethylene preform is foamed by such a method using two foaming stages.

Abstract: Method for treatment of a solid material submerged in a body of liquid wherein the material is sticky and/or has relatively low tensile strength. The material being treated is supported, while so submerged, by a dynamic boundary layer of a liquid material between the treated material and a stationary porous restraining surface, the layer being created by the forced diffusion of said liquid through the pores of said stationary surface. The method is illustrated by heating and thereby foaming a strip of heat foamable thermoplastic resin while it is held submerged in a denser heat transfer liquid by a dynamic layer of said heat transfer liquid, said layer of heat transfer liquid being created by the forced diffusion thereof through a porous plate in operative communication with a pressurized chamber containing a supply of said liquid.

Abstract: An elastomeric or thermoplastic polymer, such as polyethylene, is mixed with silane for grafting onto the polyethylene; after grafting the material is extruded around a cable, a conductor, tubing or the like, but just prior to extrusion moist nitrogen is forced into the extruder so that the material will expand to foam, the cells being filled with moist gas so that the cell walls crosslink to stabilize the resulting foam sheath.

Abstract: A novel method of making foamed, crosslinked low density polyethylene utilizing as dual crosslinking/blowing agents, organic peroxides of the formula: ##STR1## where each R is a t-alkyl group bonded through its tertiary carbon atom and having 4-8 carbon atoms; and R' is an alkyl group of 1-6 carbon atoms.

Abstract: A cross-linked, cellular elastomeric composition is made from a formulation which includes one or more natural and/or synthetic rubbers, a cross-linking agent, a monomeric metallic salt of an ethylenically-unsaturated carboxylic acid and a blowing agent. The metallic salt is preferably basic zinc methacrylate. The composition may be used to provide a core for a tennis-ball or a sponge for a table-tennis bat. The former use enables advantage to be taken of the properties hitherto only found in pressurized playballs, while the latter use leads to a marked increase in the speed of the ball when struck by the bat.

Abstract: The invention relates to a method of producing molded bodies of expanded plastic having a predetermined density, based on a starting material in granulate form to which a blowing agent and optionally a cross-linking agent have been added, said starting material being introduced into an injection molding machine/press in which it is heated and injected/pressed into a mold. In order to obtain an efficient production process without loss of raw material and a product whose density can be determined in advance, the material in the injection molding machine/press is heated to a temperature which is below the temperature required to initiate the reaction of the blowing agent/cross-linking agent, and the blank thus formed is subsequently transferred to an expansion mold having the shape of the desired final product, but larger, than the blank. The blank is caused to expand in the expansion mold and final expansion takes place outside the expansion mold.

Abstract: A blend of high and low density polyethylene and azodicarbonamid added as blowing agent is heated in an extruder to a temperature above the melting point of the high density component and fed to a shear head having a hollow rotating mandrel through which tubing is fed for depositing thereon a hose at the nozzle exit of the head. A peroxide is fed to the shear head for mixing with the polymer blend and immediately initiating crosslinking; blowing begins just prior to the depositing, the material being already crosslinked to a considerable extent.

Abstract: The strip comprises a tubular section of thermoplastic material, e.g. PVC, and a fill comprising a matrix of methylmethacrylate with silicate spherules as a filler, reinforced by glass filaments under tension. In production, cold methylmethacrylate is pressed in the extruded section while it is still hot.

Abstract: Novel processes and compositions are provided for the preparation of foamed, crosslinked polyethylene utilizing cyclic peroxyketal crosslinking/blowing agents. The novel compositions include esters of thiodipropionic acid as activators.

Abstract: Expanded particles of a crosslinked polyolefin resin, each particle with uniformly spherical shape, having an average diameter of 1.4 to 5.5 mm, an average expansion ratio of 18 to 37 and specific compression coefficient of 1.6 .times. 10.sup.-3 to 4.0 .times. 10.sup.-3, are found to be produced by two-step foaming operations. They are useful for various purposes such as filtrating material, fillers in stuffed specimens and, especially for preparation of molded articles having constricted portions, giving excellent moldings having smooth surface without failure at corner or edge portions.

Abstract: A process for the production of polyolefin foam materials from crosslinked polyolefin foam scraps includes the steps of comminuting scraps of crosslinked polyolefin-containing foam; admixing the comminuted scraps with a synthetic resin on a polyolefin basis; compressing the resulting admixture at a temperature lying below the decomposition temperature of the crosslinking agent to form an aggregate product; comminuting this product to form a particulate material; plasticizing the particulate material at a temperature lying below the decomposition temperature of the crosslinking agent to form a shaped article; and crosslinking and expanding, i.e. foaming, the shaped article by heating the article to above the decomposition temperatures of the crosslinking agent and of the blowing agent.

Abstract: In a process for producing an olefinic resin foam which comprises the steps of forming a composition comprising an olefinic resin, a chemical blowing agent and a crosslinking agent into an unfoamed sheet-like or rod-like shaped article and foaming it by heating, the improvement wherein the heat-forming step is carried out in an oxygen-free atmosphere or in an atmosphere containing not more than 10% of oxygen.

Abstract: A process for the production of foam materials, particularly polyolefin foam materials, from crosslinked polyolefin scraps involves comminuting and compressing crosslinked polyolefin foam scraps at a temperature lying below the decomposition temperature of a crosslinked agent contained therein, plasticating the resulting comminuted product also at a temperature lying below the temperature of the crosslinked agent, forming a shaped article from the plasticated material and thereafter crosslinking and expanding the shaped article by heating above the decomposition temperature of the crosslinking agent and of a blowing agent contained within said material. The initial foam scraps are obtained during the formation of a crosslinked polyolefin foam containing material.

Abstract: Membranes, which may be used for the separation of gases, comprise a thin film of a semi-permeable material composited on a porous support member. The membranes are prepared by passing a support member through a solution of a halogenated hydrocarbon solvent containing a semi-permeable membrane forming prepolymer and cross-linking agent. This step is then followed by the cross-linking of the prepolymer by treatment at an elevated temperature. The process may be exemplified by passing one finely porous surface of a cellulose nitrate-cellulose acetate support member through a solution of dimethyl silicone in a halogenated solvent such as trifluorotrichloroethane followed by treatment at a temperature in the range of from about 50.degree. to about 150.degree. C. to form the desired membrane.

Abstract: The pore size distribution of a microporous separation medium, such as a membrane or gel, is modified so as to provide it with a sharp upper cut-off of preselected molecular size. The modification is effected by first filling the pores of the separation medium with a volatile liquid, and then evaporating a controlled amount of the volatile liquid to form voids at the entrances to the pores. A concentrated solution of a cross-linkable or polymerizable pore-blocking agent, such as a protein, enzyme or polymeric material, is then applied to the surface of the separation medium. The pore-blocking agent is a material which is insoluble in the volatile liquid and whose molecular size distribution has a lower limit corresponding to the preselected molecular size, whereby the pore-blocking agent selectively enters only those pores larger than the preselected size and remains in the voids at the entrances to the pores.

Abstract: A process of forming an embossed surface covering is disclosed. The process comprises forming a cross-linkable foam comprising at least one polymer and having a first phase region and a second phase region; heat the foam to a temperature at least equal to the flow temperature of the first phase region; compressing the heated foam and cooling the foam while compressed; cross-linking a portion of the compressed foam; and reheating the compressed foam to permit the noncross-linked portion of the foam to return or "pop back" to substantially its precompressed shape and thus form an embossed surface covering.

Abstract: A crosslinked, soft, flexible, closed-cell foam of chlorinated high density polyethylene and a process for the preparation thereof, comprising admixing a high density chlorinated polyethylene with a thermally decomposable chemical foaming agent at a temperature below the decomposition temperature of said foaming agent, molding the chlorinated high density polyethylene into desired form at a temperature below the decomposition temperature of the foaming agent, subjecting the molded chlorinated high density polyethylene to irradiation cross-linking at a temperature below the decomposition temperature of said foaming agent and contacting, in a substantially oxygen-free environment, the crosslinked chlorinated high density polyethylene with a heat transfer medium maintained at a temperature of from about 150.degree. C. to about 350.degree. C. for a period sufficient to form the desired product.

Abstract: A plastic foamed sheet of excellent quality is produced by preheating in a chamber including a conveyor means for continuously conveying a thermoplastic resin sheet containing a heat-decomposable blowing agent in the horizontally supported state and a heating means for heating the sheet to a temperature lower than the decomposition temperature of the blowing agent, and foaming in a foaming chamber connected to the preheating chamber and including a heating means for heat-foaming the sheet as it is continuously conveyed while being perpendicularly suspended from the terminal of the conveyor means.

Abstract: A process for producing a crosslinked and foamed resin sheet which comprises shaping a resinous mixture comprising a thermoplastic synthetic resin and a heat-decomposable blowing agent into a sheet form, applying a high-energy ionizing radiation to the resulting foamable resin sheet to crosslink the resin sheet, and then heating the resulting crosslinked foamable resin sheet to the decomposition temperature of the blowing agent or to a higher temperature; wherein the high-energy ionizing radiation has a range of at least 0.7 .rho.d g/cm.sup.2 in which d is the thickness in cm of the foamable resin sheet, and .rho. is the density in g/cm.sup.3 of the foamable resin sheet, and a low-energy ionizing radiation with a range of not more than 0.6 .rho.d g/cm.sup.2 in which d and .rho. are as defined is applied to the foamable resin sheet before, during or after the application of the high-energy ionizing radiation.

Abstract: An extrusion foamed article with a large cross-sectional area is made by extrusion foaming a mixture of an ionomer resin and a styrenic resin utilizing a volatile blowing agent. The process permits economic production of a novel thick, foamed article having well balanced properties.

Abstract: Foamed bodies having chemically embossed patterns are prepared by a first method comprising forming a composition containing a vinyl chloride resin, a synthetic rubber material capable of forming sulfur bridges, a blowing agent, a vulcanizing agent (sulfur) and a vulcanization promotor (metal oxide) into a sheet, printing an ink containing a vulcanizing accelerator into a desired configuration onto the sheet, drying and curing the printed sheet and then heating the sheet to decompose the blowing agent thereby foaming the sheet; and a second method comprising forming a composition containing a vinyl chloride resin, a synthetic rubber containing terminal groups capable of reacting with an isocyanate, and a blowing agent, printing an ink containing an isocyanate into a desired configuration onto the sheet, drying the printed sheet and then heating the sheet to decompose the blowing agent thereby foaming the sheet.

Abstract: This invention relates to a novel elastomeric foamed material which has surprisingly been found to exhibit a variety of unusual and desirable features both in its physical properties and in its process of manufacture. These foamed compositions of a lightly sulfonated elastomeric gum contain a nonvolatile polar plasticizer and preferably extenders such as oil and fillers. These elastomer foams exhibit an unusual profile of physical properties including melt reprocessability of fabricated articles, and high temperature reshaping of foamed objects while maintaining a good foam structure. These novel foams can be manufactured with relatively uniform cell structures and with small cell sizes at foam densities from near bulk density to less than 0.1 g/cc.

Abstract: A method and apparatus are provided for the extrusion of a thermoplastic material in modified form in which the thermoplastic material is introduced into the barrel of a screw extruder, and is heated and forced through the barrel: the material is passed through valve means which together with the temperature of the material is effective to produce a melt transition in the material at a predetermined point and to thoroughly mix the material; subsequently, the material is forced into a low pressure zone in the barrel where a modifying agent is introduced into the material; the resultant mass is forced out of the low pressure zone, and is passed through a mixing means effective to intensify the dispersion of the modifying agent in the mass, the mass is extruded and the extruded material collected.

Abstract: The invention relates to an apparatus for the continuous production of continuous plastics foam webs from extruded polyolefin webs containing peroxide and blowing agent by cross-linking on a perforated conveyor belt with subsequent foaming, suspended freely in space into a continuous heating furnace.

Abstract: Continuous method and apparatus for treatment of a solid material submerged in a body of liquid wherein the material is sticky and/or has weak tensile strength. The material is supported, while it is so submerged, by a dynamic layer of the liquid lying between the material and a moving surface. The method is illustrated by heating and thereby foaming a strip of heat foamable thermoplastic resin while it is held submerged in a denser heat transfer liquid by a dynamic layer of that liquid generated by a moving belt above the foaming material. In an example, expandable high density polyethylene strip is foamed continuously while it is so held submerged in molten salt.

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.

Abstract: A non-woven rug, or the like, is formed by heat sealing a covering material at spaced intervals to a plastic backing and thereafter shrinking the backing to bulk the facing fabric. The heat sealing of the facing fabric to the backing causes a partial loss of orientation in the seal area therein bringing about a bulking or crinkling of the backing. The backing is preferably of a thermoplastic material having a foaming agent incorporated therein which is foamed after the completion of the heat sealing and heat shrinking procedures. Also included in the disclosure are the features of the backing fabric independently, i.e., incorporation of a foaming agent into a plastic which is extruded and thereafter heat sealed and/or stretch oriented and shrunk prior to the activation of the foaming agent to foam the fabric.

Abstract: A continuous method for foaming foamable thermoplastic resin by floating the resin upon a heated liquid bath while heating it from above by flooding the upper surface of the floating resin material with a blanket of a liquid at substantially the same temperature as the heated bath. In an example, the flooding liquid is pumped from the heated bath and sprayed over the upper surface of the floating resin material.

Abstract: Plastic netting, particularly for wrapping pallet loads, securely to hold the load on the pallet without heat-shrinking of the netting and providing for ventilation of the load, i.e., egress of air from the load or ingress of air to the load; a method of wrapping the load with such netting for such purpose; and the resultant wrapped pallet load.

Abstract: Polyester foam is formed by simultaneously cross-linking an unsaturated polyester resin and generating carbon dioxide as a blowing agent. The foam-forming components are divided into two equal volume parts which are metered together to effect the simultaneous reactions and form the foam. Apparatus is described for effecting the foam-forming method.

Abstract: Foamed articles are made by causing the cross-linking of a thermosetting in, preferably a polyester resin, concurrently with the production of carbon dioxide by the reaction of a carbonate with an inorganic acid. The carbonate is mixed with the resin and the acid then folded in in a progressively accelerated blending operation, whereupon carbon dioxide is generated to foam the resin, the carbonate, acid and setting time of the resin being selected to obtain an appropriate match between the progress of the foaming operation and the setting of the foam. The foam may be made in a mold coated with resin impregnated glass fibers, the impregnating resin becoming cross-linked with the foam. The impregnating resin may also be cross-linked with a resin gel coat, the glass fibers forming a tough layer between the gel coat and the foam.

Abstract: Shaped articles of organic polymer resins having cellular (foamed) structure are made from heat-expandable normally solid thermoplastic resin compositions in permeable molds particularly characterized by flooding the mold cavity and the expandable material therein with molten salt as heating medium. For example, a permeable mold, charged with pieces of polyethylene containing azobisformamide and crosslinked by electron irradiation, is immersed into a molten salt eutectic mixture of KNO.sub.3, NaNO.sub.2 and NaNO.sub.3 at about 264.degree. C, removed, cooled and washed with water, thereby forming a coherent, unitary cellular resin molded article completely filling the mold cavity.

Abstract: A method of manufacturing a foamed polyolefin sheet which comprises the steps of laminating a film of noncross-linked thermoplastic resin free from a cross-linking agent to at least one surface of a cross-linked polyolefin base sheet containing a thermally decomposable foaming agent or a polyolefin base sheet containing the above-mentioned foaming agent and a cross-linking agent, and carrying out the thermal foaming of said film-fitted sheet while placing it on a supporting member under atmospheric pressure with the film-laminated surface of the polyolefin sheet being in contact with said supporting member.

Abstract: Methods for producing bodies having chemically embossed patterns comprise: (1) adding sulphur and synthetic rubber material capable of forming sulphur bridges to a vinyl chloride resin preparation containing a foaming agent, forming the mixture into a sheet, printing embossed patterns on the sheet using an ink containing a vulcanization accelerator, drying the printed sheet and then heating the sheet to decompose the foaming agent thereby foaming the sheet; and (2) adding synthetic rubber material containing terminal groups capable of reacting with isocyanates to a vinyl chloride resin preparation containing a foaming agent, forming the mixture into a sheet, printing embossed patterns on the sheet using an ink containing isocyanates, drying the printed sheet and then heating the sheet to decompose the foaming agent thereby foaming the sheet.

Abstract: In a method for the preparation of crosslinked polyolefin foams by charging a polyolefin or its blend with other thermoplastic resins containing a crosslinking agent, foaming agent and if necessary a filler into the heated mold having a changeable cavity and, after decomposition of the crosslinking and foaming agents, retracting the moving-plate of the mold by a definite distance to increase the cavity and at the same time cooling the mold, an improvement for the preparation of the crosslinked polyolefin foams having excellent appearance and dimensional stability, comprising using a mold of which the moving-plate is constructed with a body and a sliding-piece, the body holding the piece slidably whereby the sliding-piece is left behind owing to sliding between the two even on rapid retraction of the body and then retracts at the rate corresponding to the foaming pressure of the resin, in other words, at a self-controllable rate and the mold for the preparation thereof.

Abstract: A method for producing foamed thermoplastic resin profiles with an outer skin layer of increased hardness and an inner foam structure which may be used in place of wooden articles. The outer skin has a smooth surface and a good appearance, and the inner portion enclosed by the skin has a uniform foam structure. Also, with this method an improved foaming efficiency can be obtained.

Abstract: A process for the production of cross-linked polyethylene foam layers which have an anisotropic pore structure in at least one internal layer, wherein at least three polyethylene sheets which contain equal quantities of peroxide as cross-linking agent and differing quantities of a chemical blowing agent are arranged as a multilayer structure in such a way that the two external layers are formed by the sheets which contain a smaller proportion of blowing agent, and the structure is heated, preferably in a continuous heating furnace, so that the individual sheets are cross-linked and at the same time welded together to form a laminate which is subsequently foamed by increasing the temperature to between 190.degree. and 250.degree. C.

Abstract: The invention provides a process for the production of shaped bodies and semi-finished products from polyolefins in the presence of crosslink-reinforcing coagents by addition of 0.01 to 1.0 wt % of at least one organic polymer-active radical forming agent, and brief heating with shaping before radiation to above the decomposition temperature of the radical forming agent until the radical forming agent decomposes.The process serves for the production of pipes, shaped sections and sheaths by extrusion, injection molding or extrusion pressing, especially for electric insulations, in particular for cables and lines.

Abstract: An injection molding process for forming cross-linked, foamed moldings of an ethylenic polymer by passing a molding composition comprising an ethylenic polymer/cross-linking agent/foaming agent blend through the cylinder of an injection molding machine without substantially decomposing the cross-linking agent and the foaming agent, introducing the molding composition into a molding composition holding chamber provided at the exit end of the cylinder of the injection molding machine to decompose the cross-linking agent and the foaming agent therein, and injecting the molding composition into a mold.The invention also provides apparatus for carrying out the process comprising an injection molding cylinder for conveying and plasticizing the molding composition and a molding composition holding chamber provided at the exit end of the cylinder.

Abstract: Plastic netting .[.particularly.]. for wrapping pallet loads, securely to hold the load on the pallet without heat-shrinking of the netting and providing for ventilation of the load, i.e., egress of air from the load or ingress of air to the load; a method of wrapping the load with such netting for such purpose; and the resultant wrapped pallet load.