The present disclosure provides improved polypropylene-based compositions (formulations). The present disclosure further provides improved micro-pellets (non-foamed), which comprise the improved polypropylene-based composition. The improved polypropylene-based compositions have a reduced melting point (Tm) for the polypropylene resin while maintaining the stiffness of the micro-pellets for use in foaming procedures. Also, the disclosure further provides a new, dry method of preparing expanded polypropylene beads from micro-pellets without a liquid medium or steam, which thereby simplifies the production process and saves both energy and production costs.

A material that can be formed into a porous prosthetic sleeve liner that provides particularly useful benefits for prosthetics. The material is breathable and sweat-absorbing, thus minimizing skin morbidity when used as a prosthetic liner. The material can include hydrophilic-lined continuous pores within a hydrophobic polymer, wherein the hydrophilic lining is crosslinked together with the hydrophobic polymer via non-degradable covalent interactions using chain crosslinkers.

Methods of manufacturing wall structures having high racking strength are described in this specification. The methods include spray applying a foam-forming composition into a cavity of a wall structure, wherein the wall structure is disposed in a climate-controlled spray application station and allowing the foam-forming material to expand within at least a portion of the cavity to form a foam layer deposited in the cavity. In the methods, the foam layer is formed in-situ during the manufacturing method, and the density of the foam layer is selected and the relative humidity and dew point of the air in the climate-controlled spray application station throughout the spray applying is selected so that the wall structure has a racking strength of at least 500 pounds per linear foot.

The invention relates to a chamber for steam moulding expanded or cellular materials or foams comprising an enclosure comprising at least two parts (3a, 3b), at least one part being movable to allow it to be opened and closed, and the surfaces of which are partially covered with an insulating coating, in particular the inner surface of the enclosure or the outer surface of the steam inlets.

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.

An armrest for a captain's chair of a vehicle includes an outer layer and an inner layer including a foaming agent and defining a hollow core. At least one of the inner layer and the outer layer may include a reinforcing material and/or may be varied in thickness along its length. The armrest may include a third layer defining the hollow core. A related method includes heating a parison having a first and second layers, mixing a foaming agent into the second layer prior to heating, feeding the heated parison between mold halves, clamping the heated parison by moving the mold halves together, and pushing the layers of the heated parison outward, using blown air, such that the first layer is adjacent the mold and the second layer forms a hollow core of the armrest, the hollow core being partially filled by expansion of the second layer during cooling.

A method for manufacturing sustainable products with a blown, foam structure, wherein a mass comprising at least natural polymers such as starch is passed under pressure into a mold cavity (4) or through a mold die, and the mass is heated in the mold in a manner such as to stabilize the foamed structure to form the product, wherein the method comprises prefoaming of the mass prior to injection in the mold. Preferably, the prefoamed mass is kept under pressure until insertion in the mold. The invention further relates to an apparatus to be used in said method.

A 2-step processing method to form a partly cross-linked polyurethane (PU) comprising foam having densities below 600 kg/m.sup.3, preferably in the range 20-300 kg/m.sup.3, said method comprising: A first processing which comprises at least following steps: a) providing a reactive mixture comprising an isocyanate composition comprising at least one isocyanate compound, an isocyanate-reactive composition comprising at least one isocyanate reactive compound, a crosslinking agent and a blowing agent composition comprising at least a heat activatable blowing agent which is heat activatable to achieve blowing at an activation temperature T.sub.activate, and b) allowing the reactive mixture to polymerize, optionally using a shape or mold, at a process temperature T.sub.process wherein T.sub.process<T.sub.activate and T.sub.process<T.sub.melt to form a polyurethane comprising material having a melting temperature T.sub.melt and which is solid at room temperature, and then A second processing which comprises at least following steps: c) placing the polyurethane comprising material in an autoclave, pressure vessel or pressurizable mold, d) subjecting the polyurethane comprising material to a temperature sufficient to soften the polymer material (T.sub.softening) wherein T.sub.softening?T.sub.activate in combination with an elevated pressure P.sub.1 wherein P.sub.1 is higher than atmospheric pressure (P.sub.atm), and then subsequently e) subjecting the polyurethane comprising material to a pressure reduction which is sufficient to achieve expansion (foaming) and to obtain the partly cross-linked polyurethane comprising foam

An improved process for fabricating expanded thermoplastic polymers (eTP) starting from non-expanded TP is disclosed whereby said process has improved thermal control, uses preferably environmentally friendly foaming gasses, avoids anisotropy and sticking of the eTP during the processing and minimises the duration of the charging step.

The invention relates to PUR rigid foams which can be obtained by reacting an organic polyisocyanate component B) in a specified viscosity range with a hydrogen-containing component A) which is reactive to isocyanate groups, at least containing a polyol component, water, and optionally stabilizers, catalysts, and other auxiliary agents and additives, in the presence of suitable propellants and to a method for producing same, having the steps of a) providing a mold, b) introducing the foam-forming reaction mixture of component A), the polyisocyanate component B), and propellants T) into the mold, and c) foaming the reaction mixture.