The present disclosure relates to a silicone rubber foam layer obtainable by a process that includes providing a substrate; providing a first solid film and applying it onto the substrate; providing a coating tool provided with an upstream side and a downstream side, wherein the coating tool is offset from the substrate to form a gap normal to the surface of the substrate; moving the first solid film relative to the coating tool in a downstream direction; providing a curable and foamable precursor of the silicone rubber foam to the upstream side of the coating tool thereby coating the precursor of the silicone rubber foam through the gap as a layer onto the substrate provided with the first solid film; providing a second solid film and applying it along the upstream side of the coating tool, such that the first solid film and the second solid film are applied simultaneously with the formation of the adjacent layer of the precursor of the silicone rubber foam; foaming or allowing the precursor of the silicone rubber foam to foam; curing or allowing the layer of the precursor of the silicone rubber foam to cure thereby forming the silicone rubber foam layer; optionally, exposing the layer of the precursor of the silicone rubber foam to a thermal treatment; and optionally, removing the first solid film and/or the second solid film from the silicone rubber foam layer.

The invention relates to low density fluoropolymer foam, and preferably polyvinylidene fluoride (PVDF) foam, such as that made with KYNAR PVDF resins, and articles made of the foam. The foam is produced by adding microspheres containing blowing agents to the polymer and processing it through an extruder. The microspheres consist of a hard shell containing a physical blowing agent. The shell softens at elevated temperatures and allows the expansion of the blowing agent, and microsphere to create larger voids within the polymer matrix. By proper control of the polymer composition, viscosity, processing temperature, blowing agent selection, loading ratio, and finishing conditions, useful articles such as foamed PVDF pipe, tube, profiles, film, wire jacketing and other articles can be produced. The microspheres may be added to the fluoropolymer matrix by several means, including as part of a masterbatch with a compatible polymer carrier.

A foam molding composition containing a fluororesin (A) and a compound (B) having a pyrolysis temperature of 300° C. or higher and a solubility parameter (SP value) of 8 to 15. Also disclosed is a foamed electric wire including a core wire, and a fluororesin layer or a fluororesin composition layer covering the core wire, a foam molded body, a method for producing a foam molded body, and a method for producing an electric wire.

The process of foaming a polyolefin, e.g., polyethylene, composition using as a nucleator a combination an azodicarbonamide (ADCA) and a fluororesin at a ADCA: fluororesin weight ratio of 60:40 to 20:80. The synergic effect between these two nucleating agents results in a higher nuclei density and a foamed product with a smaller cell size as compared to processes using and products produced by the use of neat PTFE or neat ADCA alone as the nucleating agent.

The invention relates to a foamable ethylene polymer composition comprising at least one antioxidant, at least one process aid and at least 80 wt % of a peroxide-treated ethylene polymer composition. The foamable ethylene polymer composition has melt strength of at least 2 cN, a density of 940 to 970 kg/m3, and dissipation factor measured at 1.9 GHz of 50-80−10.sup.−6. The invention further relates to a process for making such a foamable ethylene polymer composition, and use of the foamable ethylene polymer composition in a foamed cable insulation.

An insulated wire, having at least one foamed insulating layer composed of a thermosetting resin having bubbles, directly or indirectly on an outer periphery of a conductor, wherein the foamed insulating layer has a different bubble density in a thickness direction thereof; and a rotating electrical machine.

This invention relates to a thermoplastic elastomer composition having a type A hardness (i.e., the momentary value) of 55 or less in accordance with JIS K6253, which comprises 35 to 65 parts by weight of an olefin-based thermoplastic elastomer (A) having a type A hardness (i.e., the momentary value) of 75 or less in accordance with JIS K6253 and 65 to 35 parts by weight of a styrene-based thermoplastic elastomer (B) having a type A hardness (i.e., the momentary value) of 60 or less in accordance with JIS K6253 (with the total amount of components (A) and (B) being 100 parts by weight) and a molded thermoplastic elastomer product obtained via molding of such composition.

A polymer matrix composite comprising a porous polymeric network; and a plurality of dielectric particles distributed within the polymeric network structure; wherein the dielectric particles are present in a range from 5 to 98 weight percent, based on the total weight of the dielectric particles and the polymer (excluding the solvent); and wherein the polymer matrix composite has a dielectric constant in a range from 1.05 to 80; and methods for making the same. Polymer matrix composites comprising dielectric particles are useful, for example, as electric field insulators.

The invention relates to a foamable polymer composition comprising a polyolefin polymer which polyolefin polymer does not bear silane moieties and comprises 20 to 99.99 wt. % linear low density polyethylene, and a blowing agent in an amount of 0.01 to 3 wt. % based on the total foamable polymer composition, wherein the blowing agent consists of citric acid and/or derivatives of citric acid or mixtures thereof. Further the invention relates to a foamable polymer composition comprising a polyolefin polymer, and a blowing agent in an amount of 0.01 to 3 wt. % based on the total foamable polymer composition, wherein the blowing agent consists of expandable polymeric microspheres, and the composition does not comprise fluororesin. Further the invention relates to a foamed polymer composition obtained by foaming this foamable polymer composition. Further the invention relates to the use of the foamable composition or the foamed polymer composition for a layer of a cable and a cable comprising at least one layer which comprises the

The present disclosure discloses a foamed dielectric material, which is used to solve the problems of low production efficiency and high production cost of foamed dielectric materials at present. The foamed dielectric material is a cylinder structure or a tube structure formed by a foamed material after foaming; a plurality of gaps are cut on the surface of the cylinder structure or the tube structure, and the gap has a metal wire segment inside; and the metal wire segment in different gaps is not in contact with each other. The foamed dielectric material with such structure has the advantages such as a simple structure, an accurately controllable dielectric constant, light weight per unit volume, easy to efficiently product and stable technical index. The present disclosure further discloses a production method which may be used for producing the foamed dielectric material. In the production method, firstly a foamed rod-shaped part or a tubular part is passed through a slitting device, and passed through a buried wire device, and then truncated into a required length. The production method has the advantages such as high production efficiency, low cost, light weight and easy to control the dielectric characteristic.