Abstract: The invention relates to a process for the production of expanded or expandable polyolefin beads by impregnating polyolefin granules with a volatile blowing agent in suspension under pressure. As suspension aid, use is made of a mixture of a water-insoluble inorganic compound and a surfactant, and the impregnation is carried out in the presence of a surface-active polymer carrying carboxyl or carboxylate groups.

Abstract: A method for forming microcellular foams that causes the material to expand uniaxially during the foaming process, and a method for forming objects from the foam. Liquid crystal polymers or polymers having a planar crystalline structure are saturated with a fluid, normally a gas such as carbon dioxide. The ambient conditions are changed such that the fluid is in a supersaturated state, and the material is brought to near its glass transition temperature to induce the formation of nonspherical elongated gas-filled cells. A process for making objects, such as transducer diaphragms, from microcellular foams includes the step of forming the objects prior to the foaming process.

Abstract: There is provided a foamable poly(vinyl chloride) resin composition which can remarkably improve an expansion ratio. There is used a foamable poly(vinyl chloride) resin composition comprising 100 parts by weight of (A) a poly(vinyl chloride) resin, 0.5 to 30 parts by weight of (B) a processing aid, and 0.

Abstract: Thermoplastic polymer foams having sound deadening properties satisfactory for demanding applications are provided which have mechanical strength, which are economical to manufacture, and which are hydrolytically stable. Methods of preparing these foams are also provided. The foams are useful in sound management, cushion packaging, filtering, and fluid absorption and exhibit one or more of the following properties: 1) average cell size greater than about 2 mm; 2) substantially open-cell structure and 3) relatively large pores connecting the cells. In order that the foam be acoustically active, the foam should possess a substiantially open-cell structure and a relatively low airflow resistivity. Foams with substantially open-cell structure and relatively low airflow resistivity are prepared by mechanically opening a foam having an average cell size greater than about 2 mm. In most cases, such mechanical opening creates relatively large pores connecting the cells.

Abstract: The elastomeric composition for preparing an olefinic elastomer crosslinked foam according to the present invention contains an ethylene/&agr;-olefin copolymer (A) having a specific density and MFR, an organic peroxide (D), a crosslinking assistant (E), a foaming agent (F), an organic metal compound (G), and as necessary, a high pressure low density polyethylene (B) having a specific MFR, and an ethylene/vinyl acetate copolymer (C) having a specific amount of vinyl acetate and a specific MFR. An olefinic elastomer crosslinked foam of the present invention can be obtained by crosslinking and foaming the above composition. Further, another olefinic elastomer crosslinked foam of the present invention can be obtained by a secondary compression of the above crosslinked foam. The footwear part of the present invention is made of these crosslinked foams.

Abstract: It is an object of the present invention to provide a foamable thermoplastic elastomer composition which produces a stable foam. The present invention provides a foamable thermoplastic elastomer composition which contains: (a) 10 to 90 parts by weight of one of an olefin-based resin and rubber having a melting or softening point of 140° C. or lower, (b) 9 to 85 parts by weight of heat-expandable microcapsules expanding at 120 to 300° C., (c) 1 to 50 parts by weight of a volatile composition, wherein the components (a) to (c) total 100 parts by weight, and another aspect of the invention provides a foamable thermoplastic elastomer composition which contains; the above said (a) to (c) and (d) 50 to 99 parts by weight of a thermoplastic resin, wherein the components (a) to (d) total 100 parts by weight, and also provides a method of producing the above foamable thermoplastic elastomer composition in two stages.

Abstract: A process for making a macrocellular acoustic foam is disclosed in which a foamable gel made of a blowing agent and a polymeric resin composition is subjected to an extrusion process at a die pressure greater than the prefoaming critical die pressure but less than or equal to four times that of said prefoaming critical die pressure and macrocellular foams obtainable by that process are also disclosed which are made of: A) one or more homopolymers of ethylene, one or more C3-C20 &agr;-olefin polymers, or a combination thereof; B) one or more halogenated flame retardants; C) optionally, one or more polymers other than that of Component A; and D) optionally, one or more flame retardant synergists.

Abstract: A method of producing a bituminous foam includes supplying a bitumen in water emulsion from a tank (2) into primary and secondary heating circuits (8, 34), whereby the emulsion is heated (via heating coils 12 and 12′) and its pressure raised such that, on discharge to ambient conditions via outlet pipes (30 or 30′), the emulsion foams as water evaporates therefrom.

Abstract: The present invention is directed to processes for forming styrenic polymers, and their related end uses. In particular, the present invention is directed to processes for preparing patterns for use in metal castings.

Abstract: The present invention relates to a process for preparing a foam component, said process comprises the steps of extruding a viscous mixture from a rotating extrusion plate onto a receiving surface. Said process provides a convenient, efficient, simple means of preparing foam components, especially foam components suitable for use in cleaning compositions. The present invention also provides a foam component obtainable therefrom.

Abstract: The present invention relates to methods, materials, and products for forming a foamed product, comprising the steps of combining an epoxy-based component with an amine-based component. The epoxy component is cross-linked through a polymerization reaction catalyzed by the amine formulation. In this regard, a reactive mixture or exothermic reaction is created between the epoxy component and the amine component when combined. The heat generated by the exothermic reaction softens a thermoplastic shell of a blowing agent formulated within the epoxy component thereby enabling a solvent core within the thermoplastic shell of the blowing agent to expand from the heat generated by the exothermic reaction.

Abstract: Flexible open-celled microcellular foams based on thermoplastic polymers are useful for fluid-absorbent hygiene articles.

Abstract: Disclosed are formulations adapted to form a foamed cementitious composition, the foamed cementitious composition itself, a method of forming a hydraulic binder foam, and a method of conveying and applying the resulting foam to a substrate. A pumpable cementitious slurry is formed, the slurry is mixed with a gas such as air, and is subjected to mechanically created turbulence to generate gas bubbles and create a foam, which preferably is stabilized by a foam stabilizing agent such as polyvinyl alcohol present in the slurry. The foam is then conveyed to a nozzle or other suitable dispense point from which it is applied, for example sprayed, preferably uniformly, onto a substrate to be coated. Prior to dispensing, a set accelerator is preferably injected, which causes the foam to gel, which in turn improves the hangability of the product on a substrate. The spray material adheres to the substrate and hardens to form an insulative coating on the substrate.

Abstract: Provided are a method for forming a foamed polypropylene resin sheet in which draw down and waving are not caused in heating the foamed sheet and in which inferior appearance such as partial thickness and wrinkles is not produced on the product, and a foamed formed article having an excellent shape obtained from the same. The method comprises a heating step for heating and softening the foamed polypropylene resin sheet and a forming step for bringing the heated foamed polypropylene resin sheet into contact with a forming mold to form it into a prescribed shape, wherein the foamed polypropylene resin sheet has an expansion ratio of 1.1 to 6 times, an open cell rate of 70% or less and a sheet thickness of 0.5 to 5 mm; and the foamed polypropylene resin sheet described above is heated in the heating step in the state that it is supported on a tabular sheet support.

Abstract: The present invention relates to selectively hydrogenated block copolymers where one of the blocks is a random copolymer of a mono-alkenyl arene monomer, such as styrene, and a 1,3-cyclodiene monomer, such as 1,3-cyclohexadiene, and one of the other blocks is a hydrogenated polymer or copolymer of an acyclic conjugated diene, such as 1,3-butadiene or isoprene.

Abstract: A water-repellent composition for foaming process of a hydrophobic textile, comprising (A) a dispersion of a fluorine-containing polymer, (B) a foaming agent, and (C) a wetting agent is suitable for water-repellent treatment of the hydrophobic textile and can give easy generation of sufficient foaming.

Abstract: Foamed and expanded beads including a polyester-based resin containing at least 35 mole % of an aliphatic ester component. The foamed beads have a gel fraction of at least 5 % by weight and comprises at least one gel accelerating agent selected from fatty acids having 12-25 carbon atoms, metal salts of the fatty acids, esters of the fatty acids and amides of the fatty acids in an amount of 0.15-3 % by weight. A foam molding is obtained by heating the foamed and expanded beads in a mold.

Abstract: The present invention relates to crosslinking of porous materials made of biodegradable polymers. The method comprises: (a) placing a porous biodegradable polymer in a chamber; (b) introducing a supercritical fluid containing a crosslinking agent into the chamber to effect crosslinking of the porous biodegradable polymer; and optionally (c) introducing a pure supercritical into the chamber to wash the crosslinked polymer until the crosslinking agent is substantially removed from the polymer.

Abstract: The invention relates to a method for producing block-shaped and plate-shaped polymethacrylimide foamed materials by copolymerizing methylacrylic acid and methylacryl nitrile, by subjecting the copolymerizate to a post-polymerization and cyclization in order to form polyimide, and by converting the same into a foamed material. The invention is characterized in that the copolymerization is carried out in the presence of a mixture containing at least three initiators with graduated half-life periods. The polymerization can be controlled especially well and yields polymerizate plates with thicknesses of up to 80 mm which can be easily foamed. The invention makes it possible to produce filling materials, especially plates and blocks containing electrically conductive particles.

Abstract: The present invention relates to a process for preparing polyisocyanate polyaddition products by reacting (a) polyisocyanates with (b) relatively high molecular weight compounds containing at least two isocyanate-reactive hydrogen atoms and (c) chain-extending agents, in the presence of (d) N-(aminoalkyl)pyrrolidine catalysts corresponding to formula (I) in which R is a C2-12 alkylene group (optionally containing O or N atoms but not isocyanate-reactive groups) and R′ is hydrogen or a C1-4 alkyl group, (e) optionally, other known catalysts, and (f) other known additives.