Compositions are provided including an uncrosslinked thermoplastic nitrogen-containing matrix material and composite particles distributed in the matrix material. The composite particles each include a chemical blowing agent particle encapsulated within a shell including an uncrosslinked thermoplastic material. The uncrosslinked thermoplastic material exhibits at least a certain minimum complex viscosity at a decomposition temperature of the chemical blowing agent particle. Also described are foam compositions and particles including the foam compositions, such as a sheet or multilayer construction. Composite particles are further provided. Methods of making the foam compositions are additionally described herein. Also, polishing pads, polishing systems, and methods of polishing a substrate are provided.

An object of the present invention is to provide a gas generating agent having an appropriate initial decomposition temperature, generating a large amount of gas, and generating only a small amount of ammonia gas. The object can be accomplished by a gas generating agent containing a guanidine derivative represented by the following formula (1).

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A polyolefin-based resin foamed sheet includes a polyolefin-based resin, wherein a thickness of the foamed sheet is 0.05-0.5 mm, a 25% compression hardness defined in JIS K6767(1999) is 20-100 kPa, a ratio of cell sizes in longitudinal and thickness directions is 9-30, a ratio of cell sizes in width and thickness directions is 9-30, and an average cell film thickness in the thickness direction of the foamed sheet is 2-7 μm.

The polyolefin resin foam sheet is a polyolefin resin foam sheet having a plurality of cells in an inside thereof, wherein the 50% compressive strength is 120 kPa or less; the MD elongation percentage is 400% or less; and the TD elongation percentage is 200% or less.

A polymer composition including a crosslinkable thermoplastic matrix, a crosslinking agent, a blowing agent, and at least one cell opener is provided. A method of producing an open cell polymer foam from the polymer composition is also provided. The method includes heating a foamable precursor under positive pressure to a temperature greater than a decomposition temperature of the crosslinking agent and below a decomposition temperature of the chemical blowing agent to produce a primary foam. Then, the method includes heating the primary foam to a temperature greater than the decomposition temperature of the chemical blowing agent and then allowing the primary foam to cool to a temperature below a softening temperature of the crosslinkable thermoplastic polymer to form the open cell polymer foam. The produced open cell polymer foam has an open cell content of at least 80% immediately following the step of allowing the primary foam to cool.

A method of manufacturing a polyolefin foam sheet composition includes extruding a polyolefin sheet, irradiating the extruded sheet to obtain a physically crosslinked sheet, foaming the physically crosslinked sheet with heat to obtain a foamed layer, and skiving the foamed layer to obtain a foam sheet with at least one skived surface. The surface roughness of the skived surface of the foam sheet is different from the surface roughness of an unskived surface.

Present invention is related to a microwave and electromagnetic heated foaming method, mold and foaming material thereof. The microwave and electromagnetic heated foaming method comprises steps of adding a foam material into a mold, simultaneously applying a microwave and electromagnetic energy toward the mold under a normal or low pressure, and the microwave and electromagnetic energy made the foam material into molded foam body. The mold of the present invention has a microwave penetrating part and an electromagnetic heating part. The microwave penetrating part has an extruded bottom that is corresponded to a dented top of the electromagnetic heat penetrating part. By utilizing the microwave and electromagnetic energy, the present invention is about to provide an efficient way for processing the foaming material compared to the conventional infrared or electrical heated tube heating and achieve the foam method that can be executed under normal or low pressure.

A polyolefin-based resin foamed sheet includes a polyolefin-based resin, wherein a thickness of the foamed sheet is 0.05-0.5 mm, an apparent density is 200-500 kg/m.sup.3, a tensile strength at 100% elongation in at least one direction of a longitudinal direction (MD direction) and a width direction (TD direction) of the sheet is 3.5-12 MPa, and a ratio of a tensile breakage strength and the tensile strength at 100% elongation in at least one direction of the MD direction and the TD direction of the sheet is 1.0-1.8.

This disclosure relates to a foamable resin composition containing a nitrogen gas-generating compound and methods of using the composition for loss circulation control.

A process for producing a polymeric article is provided that includes: sequentially filling a female mould (11) with a first, second, and third batches, wherein the first and third batches include first and third polymeric materials (1p, 3p), and the second batch includes a second polymeric material (2p) and a blowing agent (2b), closing the thus filled cavity with a lid (12) to form a mould defining a closed cavity (10c) of constant volume in time, heating the mould (10) to a processing temperature, to melt the first, second, and third polymeric materials (1p-3p) and to expand the second polymer agent by activation of the blowing agent, cooling and removing the lid (12) to open the cavity and extracting the polymeric article. At least the second polymeric material (2p) includes at least 50 wt. % of recycled polymer in the form of shredded flakes.