Abstract: Expandable styrene resin beads are described, which, when expanded to a bulk density of 20 g/l, give pre-expanded beads in which the number of cells present along those surface parts of radii which range from the bead surface to a depth of 0.2 mm from the surface is from 3 to 20 per mm and the number of cells present along those inner parts of the radii which range from a depth of 1 mm from the bead surface to the bead center is 10 or larger per mm, the number of cells present along said surface parts being smaller than the number of cells present along said inner parts.

Abstract: A strippable pressure-sensitive adhesive and an adhesive material using the same are disclosed, adhesive comprising a highly elastic base polymer whose dynamic modulus of elasticity is in the range of from 250,000 to 10,000,000 dyne/cm.sup.2 at a temperature between ambient temperature and 150.degree. C. with a small rate of change with temperature, having incorporated therein a blowing agent, which adhesive reduces or loses its adhesiveness on expansion or blowing of blowing agent. The adhesive and adhesive material are easily re-applied, is capable of satisfactorily following the shape of an adherent during forming of the adherent, reduces its adhesiveness on heating, and is applicable to various adherents with excellent workability.

Abstract: A continuous process for making moldable foam beads comprising a non-crosslinked or crosslinked thermoplastic polymer foam are produced by mixing a composition comprising a non-crosslinkable or crosslinkable thermoplastic polymer or a thermoplastic polymer with a crosslinking agent, additives to achieve specific properties, a blowing agent, extruding the admixture under pressure, crosslinking, when applicable, the admixture under pressure, modulating the admixtures temperature to achieve the desired foaming properties, and then expanding the admixture in a zone of lower pressure to form a foam bead that can be molded.

Abstract: The invention relates to a process for the preparation of bead shaped, expandable polystyrene by the polymerization of styrene in an aqueous suspension in the presence of dimeric .alpha.-methylstyrene as a regulator and a C.sub.3 to C.sub.6 hydrocarbon as a blowing agent, whereby one first reports the content of saturated hydrocarbons, having a boiling point between 70.degree. and 170.degree. C., in the styrene and dimeric .alpha.-methylstyrene, and then enough saturated hydrocarbons, having a boiling point from 70.degree. to 170.degree. C., are added before, during or after the polymerization so that their total content in the suspension is from 0.1 to 0.8 weight percent, based on the styrene.

Abstract: A method and apparatus for producing a lightly crosslinked polyolefin foam and articles made therefrom is disclosed. According to the method, a polyolefin resin is lightly crosslinked, mixed with a blowing agent, forwarded as a molten gel admixture through an extruder, cooled, and expelled from a die into a zone of lower pressure, e.g., the atmosphere or a controlled pressure zone, to produce a uniform fine celled expanded shape.

Abstract: Bead-form, expandable styrene polymers containing, based on the styrene polymer, from 0.005 to 1.5% by weight of polyethylene wax and from 0.005 to 1% by weight of dimeric .alpha.-methylstyrene, and a process for the preparation thereof.

Abstract: The present invention relates to porous crosslinked polymeric microbeads having cavities joined by interconnecting pores wherein at least some of the cavities at the interior of each microbead communicate with the surface of the microbead. Approximately 10% of the microbeads of the present invention are substantially spherical or substantially ellipsoid or a combination of the two. The present invention also relates to a process for producing a porous, crosslinked polymeric microbead as well as the product of this process. This process involves combining a continuous phase with an aqueous discontinuous phase to form an emulsion, adding the emulsion to an aqueous suspension medium to form an oil-in-water suspension of dispersed emulsion droplets, and polymerizing the emulsion droplets to form microbeads. Also included in the invention are modifications of the microbeads as well as methods for using the microbeads in a variety of applications.

Abstract: Microsphere beads are mixed with a surface barrier liquid or mixture of such a liquid with a solid effective to prevent agglomeration and surface bonding of the microspheres; by the control of the application of heat and balancing temperature and active mixing, removal of water from the microspheres is achieved.The surface barrier liquid or mixture of such a liquid with a solid in the present invention is any one of a wide diversity of materials which meet the requirements of the intended function, i.e., to prevent the agglomeration of the microspheres during the process. Suitable materials include, by way of example, plasticizers, diluents, extenders, monomers and oligomers, and the like.

Abstract: The subject invention pertains to a continuous process for expanding thermoplastic minipellets, particularly polypropylene. The minipellets are continuously expanded by continuously charging and mixing water and minipellets in a slurry tank to form a slurry which is subsequently pressurized. A blowing agent such as butane is entrained into the pressurized slurry flow, which said slurry is then heated by a heating means, such as a shell and tube heat exchanger, to the softening point of the minipellets. The heated minipellets are given the time necessary for impregnation by permitting them to flow through one or more impregnation vessels. The impregnated minipellets are released through an orifice into an expansion vessel where the blowing agent flashes off, thereby expanding the minipellets.

Abstract: A foamed article of styrene type resin, in which base resin particles are styrene type resin particles obtainable by a graft polymerization of a cis-rich polybutadiene with a styrene type monomer, a blowing agent contains n-pentane as its main component and the foamed article shows a density of 0.015-0.040 g/cm.sup.3, an average foam diameter of 60-300 micrometers and a closed cell foam rate of not less than 50%.

Abstract: A one-step emulsification process for preparing aqueous suspensions of hollow, acrylate polymer microspheres conducted in the presence of at least one acid that is not free radically polymerizable. Surprisingly, the use of such an acid eliminates the previous requirement of using a polar copolymerizable monomer in the one-step emulsification process. The hollow acrylate polymer microspheres prepared from the process of the invention may be tacky or tack-free.

Abstract: Disclosed is a compatibilized carbon black useful in melt processing of plastic material. The carbon black is coated with a compatibilizing agent which enhances the dispersibility of the carbon black in a melt of the plastic material. Further disclosed are processes for making plastic foam structures with the compatibilized carbon black.

Abstract: An expandable styrene polymer comprisinga) from 0 to 90% by weight of a styrene polymer or styrene copolymer other than b) contains at least 50% by weight of copolymerized styrene,b) from 10 to 100% by weight of a styrene/methacrylamide copolymer comprising from 0.5 to 50% by weight of at least one copolymerized N-substituted methacrylamide of the formula I ##STR1## where R.sup.1 and R.sup.2 are identical or different and are hydrogen, C.sub.1 - to C.sub.15 -alkyl, C.sub.6 - to C.sub.16 -cycloalkyl or C.sub.6 - to C.sub.20 -aryl, it being possible, if R.sup.1 and R.sup.2 contain at least 2 carbon atoms, for at least 2 carbon atoms to be linked via hetero atoms, andc) from 1 to 15% by weight, based on the sum of a) and b), of an aliphatic C.sub.3 - to C.sub.9 -hydrocarbon and/or carbon dioxide as blowing agent.

Abstract: The production of approximately spherical polyolefin foam particles having a coarse cell structure and a narrow cell size distribution by dispersion foaming is achieved by a process in which the reactor contents, which essentially comprise polyolefin particles, a liquid dispersion medium and, if desired, a volatile blowing agent, are first treated at a first temperature above the crystallite melting point T.sub.m of the polyolefin, and subsequently passed through a cooling device, in which the dispersion is brought to a second, lower temperature, and the polymer particles are then foamed at this temperature. The foamed particles can be converted into moldings by known methods.

Abstract: The present invention provides a thermoplastic microcapsule which is softened by heat, has a good thermoexpandability, and can provide a MICROBALLOON which shows a high heat resistance after thermoexpanded; such a thermoexpandable microcapsule is composed of a shell and an expanding agent therein, in which said shell is made from a copolymer essentially consisting of a polymerizable monomer having two or more polymerizable double bonds and a monomer which can produce a homopolymer having a high glass transition temperature, and said expanding agent is vaporizable at a temperature lower than the softening temperature of the copolymer.

Abstract: The invention relates to expandable styrene polymers for elastic polystyrene foams, comprisinga) from 50 to 90% by weight of polystyrene and/or a styrene copolymer containing at least 50% by weight of copolymerized styrene,b) from 5 to 30% by weight of at least one styrene-soluble elastomer,c) from 5 to 20% by weight of at least one block copolymer containing styrene as one component,d) from 1 to 15% by weight, based on the sum of a), b) and c), of a low-boiling blowing agent, and, if desired,e) conventional additives in effective amounts,where, in the unfoamed polystyrene beads, component b) is in the form of cell particles and component c) is in the form of particles having a mean size of from 0.2 to 2 .mu.m in the polystyrene phase, and to foams and foam moldings produced therefrom.

Abstract: The invention relates to expandable styrene polymers for elastic polystyrene foams, comprisinga) from 75 to 98% by weight of polystyrene and/or a styrene copolymer containing at least 50% by weight of copolymerized styrene,b) from 2 to 25% by weight of at least one styrene-soluble elastomer,c) from 1 to 15% by weight, based on the sum of a) and b), of a low-boiling blowing agent, and, if desired,d) conventional additives in effective amounts,where the unfoamed beads have a structure in which the elastomer phase is dispersed in the polystyrene phase in the form of cell particles, and to foams and foam moldings produced therefrom.

Abstract: A substantially cylindrical bar of microporous PTFE is non-fibrillated and incorporates pores within any cylindrical surface within the bar centred about the central longitudinal axis of the bar that are of substantially uniform size and are substantially uniformly distributed within that surface. The process for producing such a bar includes the step of applying a substantially radial compressive force to pre-heated and cooled granules of PTFE and subsequently re-heating and cooling the compressed granules, while a film of non-fibrillated, microporous PTFE is formed from the cooled bar, the plane of the film being perpendicular to the direction of the radial compressive force whereby the pores within any plane substantially perpendicular to the thickness of the film are of substantially uniform size and are substantially uniformly distributed within that plane and all such parallel planes.

Abstract: A process for producing expandable particles of a melt compounded blend of polyphenylene ether resin and polyolefin resin. A melt compounded blend of polyphenylene ether resin and polyolefin resin, a blowing agent and water are mixed in a pressure vessel to form a dispersion; the dispersion is heated in the sealed pressure vessel to impregnate the blowing agent in the melt compounded blend of resin particles; the dispersion is then cooled in the sealed pressure vessel; and a cooled blowing agent-impregnated, melt compounded blend of resin particles is removed from the reactor. A preferred blowing agent is Freon.RTM. 11. The particles are pre-expanded by heating, and the pre-expanded particles can be foamed in a conventional mold when heat is applied thereto. A resin molding composition comprising a melt compounded blend of heat-pre-expanded, low density, resilient polyphenylene ether resin and polyolefin resin particles having about 95.0 weight percent to about 5.

Abstract: Residual chloromethyl groups in methylene-bridged aromatic polymer adsorbents are susceptible to hydrolysis to benzyl alcohol groups and oxidation to benzoic acid groups. The introduction of these hydroxyl and carboxylic acid groups contributes to the water adsorption capacity or hydrophilicity of these adsorbents. Unfortunately, this hydrophilicity interferes with the utility of these resins as adsorbents for volatile organic compounds. By capping these residual chloromethyl groups with hydrophobic aromatic compounds prior to their opportunity to hydrolyze or oxidize, the hydrophobicity of methylene-bridged aromatic polymer adsorbents is increased and their utility for the absorption of organic compounds is enhanced.

Abstract: The invention relates to expandable styrene polymers for elastic polystyrene foams, comprisinga) from 50 to 75% by weight of polystyrene and/or a styrene copolymer containing at least 50% by weight of copolymerized styrene,b) from 5 to 30% by weight of a styrene-soluble elastomer,c) from 5 to 20% by weight of at least one block copolymer containing styrene as one component,d) from 15 to 50% by weight of at least one polyolefin,e) from 1 to 15% by weight, based on the sum of a) and b), of a low-boiling blowing agent, and, if desired,f) conventional additives in effective amounts,and to foams produced therefrom.

Abstract: The present invention relates to a method for producing expanded thermoplastic microspheres by heating. Unexpanded microspheres are dried under agitation to a dry solids content exceeding 98% by weight, preferably 99% by weight, before heating. The dried microspheres can be rewetted and then expanded by heating. The microspheres thus produced contain but minor amounts of agglomerates, The invention also comprises an apparatus for expanding the dried spheres. The apparatus has a belt conveyor (A), a device (B) for IR heating, a dosing device (C) for unexpanded spheres, and a collecting device (D) for expanded spheres.

Abstract: A continuous process for manufacturing foam beads using a simple apparatus, wherein the expansion agent can be easily recycled. Polymer particles and a dispersing medium are fed continuously to an unstirred mass transfer column having a high length to diameter ratio which is operated under pressure. The polymer particles and dispersing medium are subjected to thermal processing under pressure in the mass transfer column, and the resulting dispersion is sprayed into a low pressure space causing the polymer particles to expand. Accordingly, foam beads of constant quality and a uniform cell diameter and a uniform degree of expansion are manufactured without costly process means.

Abstract: There are provided polypropylene resin expanded particles which have a uniform bubble size, can be molded with an exceptionally low steam pressure, and can produce an expanded molded product having a good surface appearance and an excellent energy absorption property. The present particles are polypropylene resin expanded particles containing as a base resin an isotactic polypropylene resin polymerized in the presence of a metallocene polymerization catalyst.

Abstract: An expandable styrene polymer comprisinga) from 0 to 90% by weight of a styrene polymer or styrene copolymer other than b) contains at least 50% by weight of copolymerized styrene,b) from 10 to 100% by weight of a styrene/methacrylamide copolymer comprising from 0.5 to 50% by weight of at least one copolymerized N-substituted methacrylamide of the formula I ##STR1## where R.sup.1 and R.sup.2 are identical or different and are hydrogen, C.sub.1 - to C.sub.15 -alkyl, C.sub.6 - to C.sub.16 -cycloalkyl or C.sub.6 - to C.sub.20 -aryl, it being possible, if R.sup.1 and R.sup.2 contain at least 2 carbon atoms, for at least 2 carbon atoms to be linked via hetero atoms, andc) from 1 to 15% by weight, based on the sum of a) and b), of an aliphatic C.sub.3 - to C.sub.9 -hydrocarbon and/or carbon dioxide as blowing agent.

Abstract: Polymeric adsorbent resins having both the high capacity associated with microporosity and the favorable kinetics associated with mesoporosity and macroporosity are useful for the chromatographic separation of organic compounds. These resins are prepared by alkylene bridging haloalkylated, porogen modified, cross-linked copolymers.

Abstract: The present invention relates to uncrosslinked polyethylene particles for the production of expanded particles that can easily and securely produce expanded particles which can be molded without applying a special internal pressure, are excellent in moldability, such as secondary expansion, fusion and dimensional accuracy, and have a high expansion rate and to uncrosslinked polyethylene expanded particles made of said uncrosslinked polyethylene particles. The present uncrosslinked polyethylene particles for the production of expanded particles are resin particles whose base resin is an uncrosslinked polyethylene having a density of over 0.920 g/cm.sup.3 and up to and including 0.940 g/cm.sup.3 and wherein, in the DSC curve that is obtained by using a differential scanning calorimeter in such a manner that after 1 to 10 mg of the resin particles is heated to 200.degree. C. at 10.degree. C./min and then is cooled to room temperature at 10.degree. C./min, heating is again carried out to 200.degree. C. at 10.

Abstract: A compostable, biodegradable foam core board has a facing sheet adhered to a foam core sheet made of a foamable biodegradable material selected from a polyvinyl alcohol polymer, a starch-based thermoplastic polymer, a polylactic acid polymer, and other foamable, biodegradable polymers having structural rigidity when foamed. The foam core sheet has selected structural properties including a foam core weight in a preferred range of 30 to 50 lbs/msf, a foam density in a preferred range of 1.5 to 9 lbs/ft.sup.3, and a foam cell size in a preferred range of 0.30 to 0.70 mm. In one example, the foam core material is composed of a mixture of a polyvinyl alcohol polymer and high-melt-index polystyrene as a structural polymer additive. In another preferred example, the foam core material contains a blend of destructurized starch, polyethylene, polyvinyl alcohol, polyvinyl acetate, and glycerol as a plasticizer.

Abstract: The present invention provides improved compositions of expanded polytetrafluoroethylene (PTFE) and similar polymers and methods for forming and using such compositions. In its preferred embodiment, the present invention employs a mixture of PTFE and expandable thermoplastic microspheres. Through application of an energy source to the mixture, a coherent three dimensional expansion of PTFE can be achieved. The expanded mixture has many of the same beneficial properties of mechanically expanded PTFE and numerous properties previously unavailable with expanded PTFE products.

Abstract: A pre-expanded particle of a polyethylene resin based on a non-crosslinked linear very low density polyethylene having a density of 0.88 to 0.915 g/cm.sup.3 and a melt index of 0.1 to 20 g/10 min. which can be used to produce a cellular molded article having superior flexibility, excellent bonding together of the particles, and both large tensile strength and large elongation at break.

Abstract: In manufacturing hollow particles, gas is supplied from a gas cylinder to a first tank under pressure for solution in a raw material liquid in the first tank for the particles. The resulting raw material liquid is supplied to a second tank where the liquid is stirred with a dispersing medium under pressure, thereby forming a compressed emulsion in the second tank. As the compressed emulsion is discharged to the outside, it is released from the compressed state so that the gas dissolved in corpuscles of the raw material liquid in the emulsion will come out as bubbles. Thus since the corpuscles in the emulsion become hollow particles, an emulsion containing fine hollow particles of the raw material liquid as nuclei is obtained. Therefore it is possible to obtain a large quantity of fine hollow particles with ease.

Abstract: Anti-corrosive protective compositions for metal. The composition contains a curable binder, which after curing has low water and oxygen permeability, and at least one filler composed of solid parts, characterised in that the filler contains expanded polymer parts with a size of 1 to 100 micrometer.

Abstract: Hollow porous microspheres of uniform diameter and of uniform wall thickness are disclosed. The walls of the hollow microspheres comprise sintered together particles which define interconnecting voids within the walls and a single central cavity in the interior of the microspheres and inner and outer microsphere wall surfaces. The interconnecting voids are continuous and extend from the outer wall surface to the inner wall surface. The walls have uniform void content and the interconnecting voids are uniformly distributed in the walls of the hollow microspheres and the walls of the hollow microspheres are free of latent solid or liquid blowing gas materials and are substantially free of relatively thinned wall portions and bubbles. The hollow porous microspheres include microspheres in which the interconnecting voids have been closed and sealed.

Abstract: Disclosed is a compatibilized carbon black useful in melt processing of plastic material. The carbon black is coated with a compatibilizing agent which enhances the dispersibility of the carbon black in a melt of the plastic material. Further disclosed are processes for making plastic foam structures with the compatibilized carbon black.

Abstract: A process for producing expandable particles of a melt compounded blend of polyphenylene ether resin and polyolefin resin. A melt compounded blend of polyphenylene ether resin and polyolefin resin, a blowing agent and water are mixed in a pressure vessel to form a dispersion; the dispersion is heated in the sealed pressure vessel to impregnate the blowing agent in the melt compounded blend of resin particles; the dispersion is then cooled in the sealed pressure vessel; and a cooled blowing agent-impregnated, melt compounded blend of resin particles is removed from the reactor. A preferred blowing agent is Freon.RTM. 11. The particles are pre-expanded by heating, and the pre-expanded particles can be foamed in a conventional mold when heat is applied thereto. A resin molding composition comprising a melt compounded blend of heat-pre-expanded, low density, resilient polyphenylene ether resin and polyolefin resin particles having about 95.0 weight percent to about 5.

Abstract: Disclosed is a cross-linked ethylenic polymer foam structure of an ethylenic polymer material of a cross-linked, substantially linear ethylenic polymer. The substantially linear ethylenic polymer having in an uncross-linked state has: a) a melt flow ratio, I.sub.10 /I.sub.2, .gtoreq.5.63; b) a molecular weight distribution, M.sub.w /M.sub.n, defined by the equation: M.sub.w /M.sub.n <(I.sub.10 /I.sub.2)-4.63; and c) a critical shear rate at onset of surface melt fracture of at least 50 percent greater than the critical shear rate at the onset of surface melt fracture of a linear ethylenic polymer having about the same I.sub.2 and M.sub.w /M.sub.n. Further disclosed is a process for making the above foam structure.

Abstract: Conductive, polymeric, inherently tacky, solvent-insoluble, solvent-dispersible, elastomeric, pressure-sensitive adhesive microparticles having an average diameter of at least about 1 micrometer, said microparticles having an ionic conductive material present on said surface, and anti-static pressure-sensitive adhesive tapes made therefrom.

Abstract: A method for preparing an improved porous polymer bead which comprises the following steps: introducing a mixture comprising a purified monomer, initiator and pore-forming agent into a 4-necked reactor with a suspension stabilizer and aqueous solution, suspending the mixture to provide homogeneous organic droplets at a temperature sufficiently low so as not to decompose the initiator, increasing the temperature gradually to a final reaction temperature and maintaining the temperature at the final temperature to react completely by suspension-polymerization the monomers in the individual organic droplet to provide the porous polymer bead, separating the bead, washing the bead with water, acetone and tetrahydrofuran, successively, and drying the bead, precipitating the bead in a solution mixed with monomer nd thinner to fill the pores of the porous bead with the diluted monomers, and introducing in a 4-necked reactor with a suspension stabilizer and aqueous solution, and by suspension-polymerization again, to c

Abstract: A process for producing hollow particles of crosslinked melamine resin having a uniform particles diameter, said process comprising subjecting a water-soluble methyl-etherified-melamine resin precondensate to condensation reaction in the presence of a curing catalyst in an aqueous solution containing a water-soluble polymer with carboxyl groups or water-soluble copolymer of ethylenically unsaturated carboxylic acid monomer, when the reaction liquid becomes turbid, adding to the reaction mixture a substance which dissolves or swells the melamine resin, and continuing the condensation reaction, if necessary.

Abstract: A method of making liquid toner for electrophotographic imaging by forming a mixture of a polyamide polymer, a good solvent therefor and a particulate pigment, heating the polymer/pigment/solvent mixture to form a solution thereof, cooling the resulting solution to precipitate fine polymer-encapsulated pigment particles of generally uniform size and morphology, removing the precipitated particles, removing the solvent and redispersing the resulting particles in dispersant medium along with a charge-control agent to form the liquid toner. A steric stabilizer can be added to the polymer-encapsulated pigment particle dispersion.

Abstract: Microsphere wet cake is mixed with a surface barrier coating effective to prevent agglomeration and surface bonding of the microspheres, and removing water by drying with continuous mixing at high shear. In a subsequent step, by the control of the application of heat and balancing temperature and low shear mixing, it is possible to also control expansion of the microspheres.The surface barrier coating in the present invention is any one of a wide diversity of materials which meet the requirements of the intended function, i.e., to prevent the agglomeration of the microspheres during the process. Suitable materials include, by way of example, dry inorganic pigments or filler materials, and the like, and related organic materials.

Abstract: Disclosed herein is a method of producing foamed particles of a polyolefin resin, which are prevented from fusion-bonding among the particles upon their production, and exhibit excellent moldability without impeding fusion bonding property among the foamed particles upon their molding. The method includes dispersing the particles of the polyolefin resin along with a finely particulate silicate mineral as a dispersing agent and at least carbon dioxide as a foaming agent in a dispersion medium in a closed vessel, heating the dispersion to impregnate the resin particles with the foaming agent, and then releasing the resin particles and dispersion medium into an atmosphere of a pressure lower than the internal pressure of the vessel, thereby expanding the resin particles.

Abstract: Isotropic porous polymer beads having a high surface porosity and large pore diameters from about 0.002 to about 5 microns are produced from solutions of a polymer or a copolymer by a thermally-induced phase separation process. The use of mixed solvent-non-solvent combinations as solvents for the polymers, produces high pore content, substantially spherical beads having a morphology ideally suited to the chromatography of large molecules, such as proteins, and for enzyme-binding.

Abstract: An artificial soil made from thermoplastic resin foamed particles is disclosed, in which a plurality of thermoplastic resin foamed particles and a plurality of fine substances are bonded to each other by heat fusion of the thermoplastic resin foamed particles to form a porous structure. The artificial soil is excellent in not only air permeability, hydrophobic properties, and draining properties but also water retention and fertilizer retention.

Abstract: Process for producing foamable particles of styrenic polymers, which consists in submitting said particles to a partial loss of foaming agent, performed in an oven at a lower temperature than the glass transition temperature (Tg) of said particles.

Abstract: Bead-form expandable styrene polymers are obtained by suspension polymerization of styrene with addition of from 1 to 10% by weight of C.sub.3 - to C.sub.7 -hydrocarbons and/or carbon dioxide as blowing agent and, if desired, conventional additives, using, as suspension stabilizer, a mixture of magnesium pyrophosphate, a sulfonate group-containing extender and an alkali metal carboxylate or alkaline earth metal carboxylate, the magnesium pyrophosphate being prepared immediately before the polymerization by combining an aqueous solution of alkali metal pyrophosphate with at least the stoichiometrically necessary amount of a magnesium salt.

Abstract: Disclosed is a process for making closed-cell, alkenyl aromatic polymer foam packing bodies. An alkenyl aromatic polymer material is heated to form a melt polymer material. The melt polymer material comprises greater than 50 percent by weight alkenyl aromatic monomeric units. A blowing agent is incorporated into the melt polymer material at an elevated pressure to form a foamable gel. The blowing agent has about 20 weight percent or more based upon the total weight of the first blowing agent selected from the group consisting of carbon dioxide and ethane. The foamable gel is extruded through a die to form a foam strand. The foam strand is pelletized to form a plurality of foam bodies. The bodies are further expanded by exposing them one or more times to heated air or steam. Preferably, the bodies are allowed to age for a preselected period of time after pelletizing and between subsequent expansions.

Abstract: The invention relates to an expandable styrene polymer, comprising(a) a styrene polymer,(b) from 1 to 10% by weight, based on (a), of a blowing agent or blowing agent mixture,(c) from 0.02 to 0.25% by weight, based on (a), of a first coating containing a coating composition comprising(c.sub.1) a bisamide made from a C.sub.2 -C.sub.8 -alkylenediamine and an aliphatic C.sub.6 -C.sub.20 -carboxylic acid and(c.sub.2) a conventional antistatic,in a (c.sub.1):(C.sub.2) weight ratio of from 1 to 50,and, if desired, further coating compositions or coating composition mixtures and conventional additives in effective amounts, and to a process for the preparation of screen fractions of bead-form, expandable styrene polymers prepared by suspension polymerization.

Abstract: Disclosed is composite hollow particles which are excellent in solvent resistance and mechanical stability and have strong walls and which can be easily synthesized. The composite hollow particles are prepared by uniformly dispersing the following ingredients in an aqueous medium;(a) an ethylenically unsaturated monomer having at least two radical polymerizable double bonds in one molecule,(b) another polymerizable monomer which is different from the monomer (a),(c) organic particles having an average particle size of 0.01 to 5 micrometer,(d) a initiator, and(e) a dispersant,and then dispersion-polymerizing.

Abstract: A stabilized powdered endothermic blowing agent .[.which.]. is a mixture or a polycarboxylic acid and an inorganic carbonate, .[.and.]. .Iadd.the .Iaddend.polycarboxylic acid and inorganic carbonate each having been surface treated with a component which prevents water from being absorbed thereby. The blowing agent is incorporated into a polymeric concentrate used for producing foamed products.