Abstract: Pellets of a chlorinated vinyl chloride resin composition comprising inorganic materials, a solvent and a blowing agent; a pre-expanded particle of a chlorinated vinyl chloride resin comprising inorganic materials and a solvent and a process for preparing the pre-expanded particle of the chlorinated vinyl chloride resin containing inorganic materials which comprises kneading a chlorinated vinyl chloride resin, inorganic materials and a solvent, pelletizing the kneaded mixture, impregnating a physical blowing agent into the resulting pellets and pre-expanding the pellets. The present invention makes it possible to be contained a large amount of inorganic materials in a chlorinated vinyl chloride resin by forming a uniform gel phase of the chlorinated vinyl chloride resin and the solvent and wrapping inorganic materials in the gel phase. A foamed article produced by employing pre-expanded particles of the chlorinated vinyl chloride resin containing inorganic materials has an excellent heat resistance, i.e.

Abstract: Improved reexpandable shrunken foam bodies of styrene-acrylonitrile type resin possessing an ability to reexpand to the original volume of the highly foamed state when left standing at room temperature under atmospheric pressure and a method for the manufacture of such reexpandable shrunken foam bodies.The aforementioned shrunken foam bodies are obtained by causing a styrene-acrylonitrile type resin to contain a prescribed large amount of a specific foaming agent exhibiting a slow gas permeation speed to the base resin and possessing the boiling point exceeding a fixed lower limit, heating the resin with steam thereby setting it to foam highly, and releasing the foamed resin into the atmosphere to be cooled and shrunk therein.The aforementioned shrunken foam bodies are convenient for the purpose of transportation and storage. They are useful as fillers intended to absorb shocks and insulate heat.

Abstract: Production of coagulated dispersion grades of PTFE using an aqueous emulsion polymerization process which employs an initiator system comprising disuccinic acid peroxide and ammonium sulphite, the latter being added during the course of the polymerization. The resulting polymer can be fabricated into porous products of improved properties.

Abstract: Pellets of a chlorinated vinyl chloride resin composition comprising inorganic materials, a solvent and a blowing agent; a pre-expanded particle of a chlorinated vinyl chloride resin comprising inorganic materials and a solvent and a process for preparing the pre-expanded particle of the chlorinated vinyl chloride resin containing inorganic materials which comprises kneading a chlorinated vinyl chloride resin, inorganic materials and a solvent, pelletizing the kneaded mixture, impregnating a physical blowing agent into the resulting pellets and pre-expanding the pellets. The present invention makes it possible to be contained a large amount of inorganic materials in a chlorinated vinyl chloride resin by forming a uniform gel phase of the chlorinated vinyl chloride resin and the solvent and wrapping inorganic materials in the gel phase. A foamed article produced by employing pre-expanded particles of the chlorinated vinyl chloride resin containing inorganic materials has an excellent heat resistance, i.e.

Abstract: A foamed and expanded low density polyethylene sheet or tube possesses both superior buoyancy and thermal resistance characteristics. The sheet or tube is made by a process comprising mixing a low density polyethylene with a blowing agent, surface activation agent and, preferably, a separation agent, heating the mixture at different temperatures to first melt the mixture and then gasify the blowing agent to expand the polyethylene cells, cooling the melted mass to partially harden and shrink the expanded cells, further expanding the cells by introducing a second gaseous blowing agent, cutting, extruding and cooling the expanded mass, forming a sheet or tube from the cooling mass, and finally cooling the sheet or tube for at least 24 hours. A buoyant, thermal resistant, water-repellent and moisture resistant sheet or tube results, which can be used, for example, as a liner for garments, including sports, business and military garments and other related equipment.

Abstract: A semi-foamed polyethylene tape for use in the molding of foamed jacket pethylene cables. After tumble mixing low density foaming polyethylene, ethylene vinyl acetate co-polymer and polyethylene color concentrate, the tape is extruded on a thermoplastic extruder having a maddox mixing screw that effectively mixes polyethylene compounds and a slot die with a suitable opening dimension. The tape is then quenched. By controlling manufacturing variables the tape is foamed to 40% to 50% of its maximum. The tape is then foamed to 100% maximum during the manufacturing of a cable assembly.

Abstract: A method for forming a molded thermoplastic foam structure comprising partially filling a mold with solvent imbibed particles of a thermoplastic resin, pressurizing said mold under conditions such as to prevent vaporization of said blowing agent during subsequent polymer melting, heating said polymer to a flowable state, releasing the mold pressure to permit foaming of the melt and expansion of the foamed polymer within the mold.

Abstract: A foamed and expanded low density polyethylene sheet or tube possesses both superior buoyancy and thermal resistance characteristics. The sheet or tube is made by a process comprising mixing a low density polyethylene with a blowing agent, surface activation agent and, preferably, a separation agent, heating the mixture at different temperatures to first melt the mixture and then gasify the blowing agent to expand the polyethylene cells, cooling the melted mass to partially harden and shrink the expanded cells, further expanding the cells by introducing a second gaseous blowing agent, cutting, extruding and cooling the expanded mass, forming a sheet or tube from the cooling mass, and finally cooling the sheet or tube for at least 24 hours. A buoyant, thermal resistant, water-repellent and moisture resistant sheet or tube results, which can be used, for example, as a liner for garments, including sports, business and military garments and other related equipment.

Abstract: Foams are prepared from a linear low density polyethylene and, optionally, other olefinic polymers, such as a low density polyethylene using a chemical cross-linking agent. The resulting cross-linked polyethylene foams exhibit an excellent balance of properties at generally lower densities than foams prepared from low density polyethylene only.

Abstract: Foamable, thermoplastic molding composition exhibiting an improved level of impact resistance is provided. The composition, which is suitable for the preparation of expanded molded parts, comprise a thermoplastic resin, preferably at least one selected from a group consisting of polycarbonate, polyalkylene terephthalate, aromatic polyester and polyester carbonate, a nucleating agent, a chemical blowing agent and an anhydride. It was unexpectedly found that the composition is suitable for the molding of articles having an improved level of impact resistance.

Abstract: A plastic foam is made by mixing a plastic material or its origin material with a blowing agent which does not react with the material, said agent having a maximum vapor pressure of 10 Pa at the highest permissible application temperature of the plastic foam and having a minimum vapor pressure of 600 Pa at a pressure at which said material is in plastic condition. A formed body of the mixture is then exposed to a pressure low enough to evaporate the blowing agent and form bubbles in the mixture, whereupon the body is cooled at low pressure to solidify the plastic material and substantially condense said agent, thereby providing said body with closed cells having a reduced internal pressure.

Abstract: A fiber having 1/2-50% substantially gas-filled and essentially all closed cells having a diameter of 0.2-25 microns and a length to diameter ratio of greater than 500 is disclosed. The fiber is made by mixing a fluorocarbon blowing agent into molten polymer, shearing the polymer at a high shear rate, extruding the polymer in a spinneret capillary at a low jet velocity and a low capillary entrance pressure and drawing down the polymer at a total extension greater than 1000.

Abstract: The production of foamed articles of polyphenylene ether resins is improved by including a modifier comprising an alpha, beta-unsaturated carboxylic acid or derivative. The resulting products are lightweight, exhibit superior heat resistance and retain flame retardancy over polyphenylene ether resins which are foamed in the absence of the modifier. Such resins are especially suited for the production of extrusion and injection foam molding material.

Abstract: Polyphenylene ether compositions rendered flame retardant with bromine-containing compounds can be foam molded into shaped articles free of streaking and without the generation of odors if the foaming agent comprises citric acid and sodium bicarbonate.

Abstract: Low density particles or beads of polyphenylene ether or polyphenylene ether-polystyrene blends are provided by incorporation of a suitable blowing agent such as pentane into the resin mixture, flowed by expansion of the resin particles by exposure temperatures near the Tg of the blend.

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: An electrically conductive polyethylene foam which is in the form of a profile, e.g. a sheet, having a closed cell foam structure and exhibiting a surface resistivity of not more than 10.sup.5 ohms/square. The sheet is prepared by a continuous method wherein an extruded, foamable, non-crosslinked preform containing a mixture of polyethylene, ethylene copolymer, chemical blowing agent, crosslinking agent and conductive carbon black is heated to produce the foam.

Abstract: The invention relates to a new blowing agent combination based on azodicarbonamide, production thereof and use thereof for foaming polymers.

Abstract: A substantially closed-celled linear polyolefin foam is made by melt processing under pressure a linear polyolefin together with a volatile blowing agent and a crosslinking agent and then expanding the polymer. Suitable crosslinking agents, including azido and vinyl functional silanes, organic peroxides, multifunctional vinyl monomers, and oxygen, increase the melt tension and melt viscosity of the polymer by lightly crosslinking the polymer with itself to enable the production of foams having improved properties in comparison with branched polyolefin foams.

Abstract: Foamable and foamed compositions comprising blends of an aromatic sulfone polymer, a linear polyester and an aromatic polycarbonate are disclosed. The composition, useful as an ovenable food container, is formed in a process in which the three components are intimately admixed, heated and extruded below or above the foamable temperature, depending upon whether a foamable or foamed composition is desired.

Abstract: An expandable alkenyl aromatic polymer composition and methods of preparation are provided. The composition is admixed with a volatile blowing agent and an expansion aid which includes a polyphenylene ether. The composition may be extruded and then expanded by exposure to steam or hot air or may be impregnated with blowing agent and then expanded.

Abstract: Moldable foam beads comprising a silane-crosslinked polyolefin foam are produced by mixing a composition comprising a silane-modified polyolefin (such as a silane-grafted polyethylene) and a silanol condensation catalyst in an extruder to produce a melt, then injecting a blowing agent into the melt at a rate effective to produce a desired foam density in the extrudate; extruding and cutting the melt to form foam beads; and exposing the foam beads to moisture to produce silane crosslinking of the polyolefin foam.

Abstract: Polyphenylene ether compositions rendered flame retardant with bromine-containing compounds can be foam molded into shaped articles free of streaking and without the generation of odors if the foaming agent comprises citric acid and sodium bicarbonate.

Abstract: An expandable polyolefin composition and a method of preparation are provided. Isobutane or mixtures of isobutane with other physical blowing agents are utilized to expand polyolefin compositions which have been modified by the addition of a stability control agent. The composition has a high degree of dimensional stability and exhibits minimal shrinkage during curing and/or aging.

Abstract: A process for dimensionally stabilizing low density foamed polyolefins utilizing a dimensionally stabilizing control additive comprising a nitrogen-containing compound (having an unsaturated leg) said compound represented by formulas (I) and (II): ##STR1##

Abstract: Foamable and foamed polyvinlyidene fluoride materials prepared by compounding the PVDF with a suitable nucleating agent of discreet insoluble particles, a blowing agent having an activation temperature above the melting point of the PVDF, and a dispersing aid to provide a substantially homogeneous powdered mixture that is then melt compounded with high shear melt blending means and then extruded and quenched to provide the foamable polyvinylidene fluoride material which can then be extruded as an insulating material on wire at a temperature sufficiently high to activate the blowing agent.

Abstract: Foamable thermoplastic compositions are described which are based on pre-compounded concentrated blends of an inorganic non-fibrous particulate foaming agent and a carrier polymer. The foamable thermoplastic polymer is selected from among aromatic polycarbonates alone or with acrylonitrile-butadiene-styrene copolymers polyesters, poly(ester-carbonates), and polyetherimides. The foaming agent may optionally be added as part of the concentrate.

Abstract: A steam expandable alkenyl aromatic polymer composition and methods of preparation are provided. The composition is mixed with a volatile blowing agent containing, as a primary blowing agent, dichlorodifluoromethane and as a secondary blowing agent, a halogenated hydrocarbon, a hydrocarbon, or an aliphatic alcohol containing from 1 to 4 carbon atoms, the secondary blowing agent having a normal atmospherpic boiling point of from about 0.degree. to about 100.degree. C. The composition may be expanded by steam immediately after extrusion foaming or may be expanded after aging of the composition which has been impregnated with volatile blowing agent.

Abstract: Foamable and foamed polyvinylidene fluoride materials prepared by compounding the PVDF with a suitable nucleating agent of discreet insoluble particles, a blowing agent having an activation temperature above the melting point of the PVDF, and a dispersing aid to provide a substantially homogeneous powdered mixture that is then melt compounded with high shear melt blending means and the extruded and quenched to provide the foamable polyvinylidene fluoride material which can then be extruded as an insulating material on wire at a temperature sufficiently high to activate the blowing agent.

Abstract: Thermoplastic resinous foams having improved resistance to oxidation are provided by the incorporation into such foams of a polyvinyl ether of a C.sub.6-30 alcohol.

Abstract: Compositions based on ethylene/vinylacetate copolymers provided with self-extinguishing properties and suitable for the preparation of foamed materials, comprising for 100 parts by weight of the EVA copolymers:from 5 to 10 parts by weight of at least a bromodiphenylether containing at least 3 bromine atoms;from 2 to 4 parts by weight of a metal oxide selected from antimony, bismuth and tungsten oxides; andfrom 0.1 to 1 part by weight of a compound having general formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.3, R.sub.4, equal or different from each other, can by hydrogen, chlorine, bromine, aliphatic hydrocarbon radicals containing from 1 to 6 carbon atoms, cyclohexyl or phenyl radicals, the nitro group or the --CN group.R.sub.5, R.sub.6, equal or different, can be hydrogen, chlorine, bromine, aliphatic hydrocarbon radicals containing from 1 to 3 carbon atoms, or alkoxy radicals containing 1 to 4 carbon atoms or ##STR2## groups, R.sub.7 being an alkyl radical containing from 1 to 3 carbon atoms.

Abstract: A foam structure having a density of less than about 20 lbs/ft.sup.3. The method of forming the same comprising forming a homogeneous melt blend under pressure of a polymer member selected from the group consisting of polyetherimide resin particles, polycarbonate resin particles, a polymer blend of polyphenylene oxide and polystyrene in particle form imbibed with a blowing agent, followed by extrusion of the same into a lower pressure atmosphere. A composition comprising said particles imbibed with methylene chloride, chloroform, 1,1,2-trichloroethane or mixtures thereof. A method of thermoforming said foam in sheet form.

Abstract: A steam expandable alkenyl aromatic polymer composition and methods of preparation are provided. The composition is mixed with a volatile blowing agent containing, as a primary blowing agent, dichlorodifluoromethane and as a secondary blowing agent, a halogenated hydrocarbon, a hydrocarbon, or an aliphatic alcohol containing from 1 to 4 carbon atoms, the secondary blowing agent having a normal atmospherpic boiling point of from about 0.degree. to about 100.degree. C. The composition may be expanded by steam immediately after extrusion foaming or may be expanded after aging of the composition which has been impregnated with volatile blowing agent.

Abstract: An expandable polyolefin composition and a method of preparation are provided. Isobutane or mixtures of isobutane with other physical blowing agents are utilized to expand polyolefin compositions which have been modified by the addition of a stability control agent. The composition has a high degree of dimensional stability and exhibits minimal shrinkage during curing and/or aging.

Abstract: Polyvinyl chloride resin in particulate form characterized by said resin particles being spherical in shape and said resin having low amounts of glassy content. Extrudates, such as pipe, formed from the novel resin of this invention have high impact strength. The novel resin of this invention has high bulk density and fast extrusion rates.

Abstract: An expandable alkenyl aromatic polymer composition and methods of preparation are provided. The composition is admixed with a volatile blowing agent and an expansion aid which includes a polyphenylene ether. The composition may be extruded and then expanded by exposure to steam or hot air or may be impregnated with blowing agent and then expanded.

Abstract: A sprayable and foamable insulating composition comprising: (A) at least one low molecular weight polymer selected from the group consisting of ethylene/alphaolefin copolymer, ethylene/alphaolefin/nonconjugated polyene terpolymer, polyacrylate, polymethacrylate, polyisoprene, polyacrylonitrile, polymethacrylonitrile and polybutadiene; (B) an effective amount of curative; and (C) an effective amount of a blowing agent having an activation temperature which is less than or about equal to the curing temperature of component (B), said composition having a Brookfield viscosity of about 100,000 centipoise or less at shear rates of 5 sec.sup.-1 or greater. A process for providing a layer of insulating foam employing such composition is also disclosed.

Abstract: Useful resilient extruded closed cell foam compositions are produced by the present invention by forming an extrudable blend comprising a heat activatible chemical blowing agent and a polymer component consisting essentially of chlorinated polyethylene and at least one other thermoplastic polymer. The amount of chlorinated polyethylene is from 0.025 to 0.5 parts per part of the thermoplastic polymer. The blend is extruded at a temperature below the activation temperature of the blowing agent to form an unfoamed thermoplastic sheet, and the sheet is thereafter heated to a temperature sufficient to activate the blowing agent and expand the sheet and produce a non-crosslinked closed cell thermoplastic foam.

Abstract: The present invention is directed to a process for the production of matte, non-blocking, thin-walled molded articles, films or tubes from polyurethane elastomers prepared from high molecular weight polyols which contain dispersed polyadducts based on polyisocyanate polyaddition products. The use of these high molecular weight polyols contained dispersed polyadducts allows for the preparation of thin-walled, molded articles which have reduced surface tackiness. The present invention is additionally directed to the molded articles produced by this process and to their use for forming polyurethane foam composites.

Abstract: A polymer foam made from a blend of a low density ethylenic polymer and styrenic polymer utilizing a volatile blowing agent and a free radical generating compound as a crosslinking agent. The free radical generating compound provides light crosslinking and increases the foamability of the polymer blend.

Abstract: Disclosed are rigid materials such as sheets, boards or tubes made of expanded polypropylene, which have a uniform specific gravity d of from about 4.1.times.10.sup.-6 to about 8.1.times.10.sup.-6 Newton/mm.sup.3, a crystallization temperature of from about 115.degree. C. to about 135.degree. C. and a flexural modulus Mf expressed in Newton/mm.sup.3 such that the ratio Mf:d is from about 1.5.times.10.sup.8 to about 1.7.times.10.sup.8 mm.

Abstract: An expandable polyolefin composition and a method of preparation are provided. Isobutane or mixtures of isobutane with other physical blowing agents are utilized to expand polyolefin compositions which have been modified by the addition of a stability control agent. The composition has a high degree of dimensional stability and exhibits minimal shrinkage during curing and/or aging.

Abstract: Disclosed are films made of expanded polypropylene, which have a uniform specific gravity d of from about 4.25.times.10.sup.-6 to about 6.50.times.10.sup.-6 Newton/mm.sup.3, a crystallization temperature of from about 115.degree. C. to about 135.degree. C. and an elastic modulus Me expressed in Newton/mm.sup.3 such that the ratio Me:d is from about 1.6.times.10.sup.8 to about 2.0.times.10.sup.8 mm.

Abstract: Styrene polymer foam is prepared using a mixed blowing agent of carbon dioxide plus ethyl chloride and optionally a fluorocarbon to provide a foam having primary cells and secondary cells formed in the struts and walls.

Abstract: The present invention relates to an improved nitro urea compound specifically the zinc salt of nitro urea useful as a blowing agent composition, its preparation and its use.

Abstract: A resin composition for a masterbatch of foaming agent, comprising:(A) 100 parts by weight of a resin component comprising(i) 100 to 20% by weight of a modified resin having an aromatic vinyl monomer unit content of 5 to 70% by weight, the aromatic vinyl monomer unit being obtained by subjecting an ethylene polymer resin or propylene polymer resin and an aromatic vinyl monomer to graft polymerization, and(ii) 0 to 80% by weight of an ethylene polymer resin or propylene polymer resin, and(B) 1 to 50 parts by weight of a chemical foaming agent.

Abstract: This invention concerns a process for producing a molded thermoplastic resin by interposing during molding a thermoplastic resin different from the thermoplastic resin to be molded as a skin layer between the die surface and the thermoplastic resin to be molded. A lubricant is provided to lubricate the interface between the die surface and the skin layer. After molding, the skin layer with lubricant is removed.

Abstract: A process for producing a polypropylenepolystyrene interpolymer which can be impregnated with a blowing agent and can then be expanded under normal conditions for polystyrene particles to low density, fine cell structure foams. The interpolymer must be viscbroken, lubricated and stress relaxed in order to foam at 100.degree. C. to densities less than 2.0 pcf.

Abstract: The low temperature impact strength of foam thermoplastic articles is increased with the addition of polysiloxane-polycarbonate block copolymer.

Abstract: Foamable and foamed polyvinlyidene fluoride materials prepared by compounding the PVDF with a suitable nucleating agent of discreet insoluble particles, a blowing agent having an activation temperature above the melting point of the PVDF, and a dispersing aid to provide a substantially homogeneous powdered mixture that is then melt compounded with high shear melt blending means and then extruded and quenched to provide the foamable polyvinlyidene fluoride material which can then be extruded as an insulating material on wire at a temperature sufficiently high to activate the blowing agent.