Abstract: 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.

Abstract: 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.

Abstract: A method of making a mould for moulding polymeric composites comprises embedding at least one layer 30 of a fibre reinforced polymer and a plurality of heating elements 24 within a spreadable ceramic material 28. The curing temperature of the ceramic material is less than the melting point of the polymer. The ceramic material is cured at a temperature less than the melting point of the polymer to yield a solid ceramic body, and the ceramic body is then heated at a temperature above the melting point of the polymer so that the latter is fused with the fibres to strengthen the mould. The mould is suitable for use for the manufacture of polymeric composites. A process for moulding polymeric composites using the mould is also described.

Abstract: A process for the manufacture of a composite article is described wherein the process comprises the steps of (i) providing on a tool (22) a fibrous material (14) having associated therewith in at least one region thereof an in-situ polymerisable non-fibrous form of a thermoplastic material; (ii) applying heat and a vacuum to said material; and additionally (iii) drawing into the fibrous material, from a source external to the tool, additional thermoplastic pre-polymer material. The process described is particularly useful for the manufacture of a large composite structure such as thermoplastic composite wind turbine blade, for example.