The invention relates to a process for production of expanded thermoplastic elastomer, said process comprising the steps of: (e) adding monomers and/or oligomers used for producing the thermoplastic elastomer with or without further starting materials into a first stage of a polymer-processing machine, (f) mixing the monomers and/or oligomers and also the optionally added further starting materials and reacting the monomers and/or oligomers to give a polymer melt in the first stage of the polymer-processing machine, (g) passing the polymer melt into a second stage of a polymer-processing machine and adding a physical blowing agent with or without further starting materials to obtain a polymer melt comprising a blowing agent, (h) molding the polymer melt comprising a blowing agent into an expanded thermoplastic elastomer.

Physical foaming a footwear component with a single-phase solution of a polymeric composition and a supercritical fluid is provided. The method include temperature conditioning a mold and then engaging the mold with a robot that conveys the mold to a press. At the press a gas counter pressure is applied to a cavity of the mold before injecting a single-phase solution of a polymeric composition and a supercritical fluid into the cavity of the mold. The process continues with releasing the gas counter pressure from the cavity of the mold and then removing the footwear component from the cavity of the mold. The parameters of the method are configured for the formation of the footwear component in an automated manner.

The crosslinked polyolefin resin foam of the present invention is a crosslinked polyolefin resin foam obtained by crosslinking and foaming a polyolefin resin composition comprising a polypropylene resin and an olefin rubber; the olefin rubber having a Mooney viscosity (ML.sub.1+4, 100° C.) of 15 to 85; the olefin rubber being contained in an amount of 10 to 150 parts by mass relative to 100 parts by mass of the polypropylene resin; the foam having a 25% compressive hardness of 30 to 70 kPa and a compressive strength ratio, 25% compressive strength/5% compressive strength, of 2.0 to 4.5. According to the present invention, a crosslinked polyolefin resin foam from which a molded product excellent in appearance can be obtained even in a secondary processing to a complicated shape without impairment of flexibility, and a molded product made from the same are provided.

The crosslinked polyolefin resin foam of the present invention is a crosslinked polyolefin resin foam obtained by crosslinking and foaming a polyolefin resin composition comprising a polypropylene resin and an olefin rubber; the olefin rubber having a Mooney viscosity (ML.sub.1+4, 100° C.) of 15 to 85; the olefin rubber being contained in an amount of 10 to 150 parts by mass relative to 100 parts by mass of the polypropylene resin; the foam having a 25% compressive hardness of 30 to 70 kPa and a compressive strength ratio, 25% compressive strength/5% compressive strength, of 2.0 to 4.5. According to the present invention, a crosslinked polyolefin resin foam from which a molded product excellent in appearance can be obtained even in a secondary processing to a complicated shape without impairment of flexibility, and a molded product made from the same are provided.

A process for producing foamed thermoplastic polyurethane particles comprises the steps of a) melting a thermoplastic polyurethane in a first extruder (E1), b) injecting a gaseous blowing agent in a second extruder (E2), c) impregnating the gaseous blowing agent homogeneously into the thermoplastic polyurethane melt in a third extruder (E3), d) extruding the impregnated thermoplastic polyurethane melt through a die plate and granulating the melt in an underwater granulation device under temperature and pressure conditions to form foamed thermoplastic polyurethane particles.

A process for producing foamed thermoplastic polyurethane particles comprises the steps of a) melting a thermoplastic polyurethane in a first extruder (E1), b) injecting a gaseous blowing agent in a second extruder (E2), c) impregnating the gaseous blowing agent homogeneously into the thermoplastic polyurethane melt in a third extruder (E3), d) extruding the impregnated thermoplastic polyurethane melt through a die plate and granulating the melt in an underwater granulation device under temperature and pressure conditions to form foamed thermoplastic polyurethane particles.

A method for producing a foam component includes providing a particulate starting material in a mold, softening the starting material, inducing a pressure change within the mold to cause foaming in at least a portion of the softened starting material without the use of a blowing agent, and solidifying the foamed starting material.

A method for producing a foam component includes providing a particulate starting material in a mold, softening the starting material, inducing a pressure change within the mold to cause foaming in at least a portion of the softened starting material without the use of a blowing agent, and solidifying the foamed starting material.

Disclosed, among other things, are ways to manufacture reduced density thermoplastics using rapid solid-state foaming and machines useful for the saturation of plastic. In one embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity. In another embodiment, a foaming process may produce layered structures in reduced density plastics with or without integral skins. In another embodiment, a foaming process may produce deep draw structures in reduced density plastics with or without integral skins. In yet another embodiment, a foaming process may utilize additives, blends, or fillers, for example. In yet another embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity.

Disclosed, among other things, are ways to manufacture reduced density thermoplastics using rapid solid-state foaming and machines useful for the saturation of plastic. In one embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity. In another embodiment, a foaming process may produce layered structures in reduced density plastics with or without integral skins. In another embodiment, a foaming process may produce deep draw structures in reduced density plastics with or without integral skins. In yet another embodiment, a foaming process may utilize additives, blends, or fillers, for example. In yet another embodiment, a foaming process may involve saturating a semi-crystalline polymer such as Polylactic Acid (PLA) with high levels of gas, and then heating, which may produce a reduced density plastic having high levels of crystallinity.