An expanded bead having a through hole and including a foamed core layer which defines the through hole therein and which is constituted of a resin composition containing two kinds of polypropylene-based resins having different melting points, and a cover layer covering the foamed core layer and constituted of a polyolefin-based resin. The expanded bead gives a DSC curve in which an endothermic peak intrinsic to the resin composition and another endothermic peak on a higher temperature side thereof appear in a specific heat of fusion ratio. Molded articles include a multiplicity of the expanded beads.

Foamed pellets contain a thermoplastic polyurethane obtainable or obtained by a process. The process involves reacting a polyol composition (PZ-1) containing at least one hydroxy functionalized polyol (P1) with a maximum of 20% of primary hydroxyl groups with a polyisocyanate (I1), to obtain a polyol composition (PZ-2) containing a prepolymer (PP-1). The process then involves reacting the polyol composition (PZ-2) containing the prepolymer (PP-1) with a composition (C2) containing a chain extender (CE) with a molecular weight<500 g/mol. Foamed pellets are obtained or obtainable by the process. The foamed pellets can be used for the production of a molded body.

A composition and method for making extruded polystyrene (XPS) foam is provided. The composition includes an infrared attenuation agent composition comprising conductive polymers to achieve an XPS foam having an improved thermal insulation performance. In some exemplary embodiments, the conductive polymers comprise doped polypyrrole and doped polyaniline. In some exemplary embodiments, the XPS foam includes a carbon dioxide-based blowing agent.

A foamed sheet includes an aliphatic polyester resin and a filler. An average foam diameter of the foamed sheet is 15 micrometers or less. An average thickness of the foamed sheet is 3,000 micrometers or less. A ratio of a length of a side of the foamed sheet in a longer direction or a side of the foamed sheet in a direction perpendicular to the longer direction to the average thickness is 250 or more.

The present invention is related to a process for the production of a vinyl aromatic (co)polymer comprising the steps of: a) mixing a fraction (A) comprising one or more monomers selected from the group consisting of styrene, alpha-methyl styrene, acrylonitrile, methyl (meth)acrylate, (meth)acrylic acid and butadiene with a fraction (B) comprising post-consumer recycled vinyl aromatic (co)polymer, wherein the weight ratio of fraction (B) to fraction (A) is comprised between 0.01/1 and 1/1, preferably between 0.05/1 and 0.5/1 b) subjecting the resulting mixture to a free-radical polymerization and polymerizing to a monomer conversion up to 90%, to obtain a polymerized mixture comprising vinyl aromatic (co)polymer; c) vacuum devolatizing the polymerized mixture and recovering vinyl aromatic (co)polymer characterized by a weight average molecular weight comprised between 100,000 and 400,000 g/mol;
wherein one or more bromine derivative capture agents are added before, and/or during and/or after at least one of the steps a) to c); and
wherein 100 parts of one or more bromine derivative capture agents comprises at least 50 parts by weight of hydrotalcite of the formula:

[Mg.sub.1-x Al.sub.x(OH).sub.2].sup.x+(CO.sub.3).sub.x/2.mH.sub.2O

wherein: 0<x≤0.5, and m is a positive number.

The present invention is also related to expandable and extruded expanded vinyl aromatic (co)polymer compositions obtained from vinyl aromatic (co)polymers comprising post-consumer and/or post-industrial vinyl aromatic (co)polymer and to a process for the production of said expandable and extruded expanded vinyl aromatic (co)polymer compositions.

A thermoplastic olefinic elastomer expanded bead, which is an expanded bead including a thermoplastic olefinic elastomer as a main component, wherein the expanded bead has an average particle diameter of 0.5 to 5 mm, the expanded bead has a heat of fusion of 60 to 80 J/g, and a difference [Tm−Tc] between a melting point (Tm) and a crystallization temperature (Tc) of the expanded bead is 20° C. or lower.

A crosslinked olefin-based thermoplastic elastomer expanded bead including a base polymer having an olefin-based thermoplastic elastomer and a brominated bisphenol-based flame retardant having a chemical structure represented by formula (1). A difference Tm.sub.TPO-T.sub.FR is −5° C. to 40° C., where Tm.sub.TPO is a melting point of the olefin-based thermoplastic elastomer and T.sub.FR is the lower of a glass transition temperature T.sub.gFR and a melting point Tm.sub.FR of the brominated bisphenol-based flame retardant. A xylene insoluble content is 5 mass % to 80 mass %. R.sup.1 and R.sup.3 in the formula (1) are monovalent substituents, R.sup.2 is a divalent substituent, and n is an integer from 1 to 6:

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Foamed articles including a foamed thermoplastic elastomeric material, methods of making the foamed articles, and methods for manufacturing articles of footwear, apparel, and athletic equipment incorporating such foamed articles are provided. In one aspect, a method for making a foamed article comprises placing an article comprising a foamable material and carbon dioxide in a vessel, maintaining the vessel at a first pressure and first temperature at which the carbon dioxide is a liquid and carbon dioxide is soluble in the foamable material, optionally exposing the infused article to a second temperature and second pressure, and subjecting the article to a third pressure and third temperature at which the infused carbon dioxide phase transitions to a gas, thereby expanding the foamable material into a foamed material and forming the foamed article.

A resin sheet includes a porous structure. The porous structure is configured to adjust transmission of a millimeter wave. The porous structure has a relative permittivity varying in stages in a thickness direction of the resin sheet from a plane on which the millimeter wave is incident, the relative permittivity varying such that a difference between average relative permittivities in two adjacent layer portions is a predetermined value or less, the layer portions each having a particular thickness smaller than a wavelength of the millimeter wave. The porous structure has, as pores, only pores each having a pore diameter equal to or less than 10% of the wavelength of the millimeter wave.

Embodiments relate to a porous polyurethane polishing pad for use in a chemical mechanical planarization and a process for preparing the same. It is possible to control the size and distribution of pores in the porous polyurethane polishing pad by using thermally expanded microcapsules and an inert gas as a gas phase foaming agent, whereby the polishing performance thereof can be adjusted.