Disclosed herein are physically crosslinked, closed cell continuous multilayer foam structures that include a coextruded foam layer containing at least one of polypropylene and polyethylene and a crosslinked, coextruded cap layer containing at least one of polypropylene and polyethylene. The multilayer foam structure can be obtained by coextruding a multilayer structure comprising at least one foam composition layer and at least one cap composition layer, irradiating the coextruded structure with ionizing radiation, and continuously foaming the irradiated structure.

A foamed resin molded article (1) including: a foamed resin layer (30) comprising a first resin which is a copolymer including a rubber component, a vinyl cyanide monomer unit and an aromatic vinyl monomer unit, and a blowing agent; and a non-foamed resin layer (50) covering the foamed resin layer (30), wherein: the non-foamed resin layer (50) comprises a second resin which is a copolymer including a rubber component, a vinyl cyanide monomer unit, and an aromatic vinyl monomer unit; and the amount of the rubber component in the non-foamed resin layer (50), determined by pyrolysis-gas chromatography/mass spectrometry (PGC/MS), is 1% by mass or more and 30% by mass or less, based on the total mass of the second resin.

Tooling and components of an injection-molding system may be used to mold a foam article. The tooling and components may include features that control parameters of the injection-molding and foaming process, such as temperature, pressure, shot size, shot placement, and the like.

Tooling and components of an injection-molding system may be used to mold a foam article. The tooling and components may include features that control parameters of the injection-molding and foaming process, such as temperature, pressure, shot size, shot placement, and the like.

A foam article, such as a cushioning element for an article of footwear, apparel or sporting equipment is provided that comprises a foam component, such as a midsole, having a number of beneficial physical characteristics. The cushioning element is a low-density foamed component with a surface skin that encases the remaining foam volume. The cushioning element has a number of foam volumes, arranged to achieve a more consistent foam component. Additionally, the cushioning element includes a series of concentric ridges extending radially outwardly from injection gate vestige locations, and a number of striation bands near the perimeter of the cushioning element. The location of the gate vestiges can be beneficially arranged to produce intersecting flow boundaries that are located away from key strain areas of the cushioning element. The cushioning element is more environmentally-friendly, requiring less energy to produce while still providing acceptable energy return and low density.

The invention is directed to a foamed injection moulded article comprising a foam composition obtained by foaming high density polyethylene having a quotient of melt strength and apparent viscosity >2 cN/K.Math.Pa.Math.s wherein the melt strength is determined as described in ISO 16790:2005 and the apparent viscosity is determined as described in ISO 11443:2014.

The invention is directed to a foamed injection moulded article comprising a foam composition obtained by foaming high density polyethylene having a quotient of melt strength and apparent viscosity >2 cN/K.Math.Pa.Math.s wherein the melt strength is determined as described in ISO 16790:2005 and the apparent viscosity is determined as described in ISO 11443:2014.

A process for producing split crosslinked polyolefin sheets comprises producing a crosslinked polyolefin foam sheet having an opposing first surface region and second surface region, and an intermediate region disposed therebetween, wherein the intermediate region is configured to have a gel content lower than an average gel content of the first surface region and the second surface region, and an average cell size larger than an average cell size of the first surface region and the second surface region; and applying a splitting force to the crosslinked foam sheet such that a controlled tear propagation travels through the intermediate region until a first side of the crosslinked polyolefin foam sheet and a second side of the crosslinked polyolefin foam sheet are separated to produce two split polyolefin foam sheets. The split crosslinked polyolefin foam sheets may comprise a skin side comprising a closed cell surface, and a split side comprising an open cell surface having peak heights of about 150 μm to about 550 μm.

A closed cell crosslinked polyolefin foam sheet comprises an opposing first surface region and second surface region, and an intermediate region disposed therebetween, wherein the intermediate region is configured to have a gel content lower than an average gel content of the first surface region and the second surface region to enable a controlled tear propagation within the intermediate region when a splitting force is applied to the closed cell crosslinked polyolefin foam sheet. For example, a ratio of a gel content of the intermediate region versus an average gel content of the first surface region and the second surface region may be about 75% or less, and a ratio of the average cell size of the intermediate region versus an average cell size of the first surface region and the second surface region may be about 125% or higher.

The present invention concerns layered foamed polymeric materials lacking discontinuities at the interface between the layers and a preparation process thereof comprising the following steps: —providing a foamable polymeric material; —solubilising said one or more foaming agents in the foamable polymeric material under pressure and at a temperature greater than 20° C.; and —releasing the pressure instantaneously; where the solubilisation step is carried out with a pressure profile of said one or more foaming agents that is variable over time.