| abstract |
The method comprises the steps of: (a) conditioning a solid preform (1) made from PET (polyethyleneterephthalate), previously obtained by extrusion, moulding or heat‑forming, adjusting the moisture concentration thereof to the concentration value thereof at equilibrium; (b) dissolving, in said solid preform (1), an inert gas, at pressure and temperature, for a sufficient period to achieve saturation, and decompression at ambient temperature, thereby resulting in the gas‑saturated solid preform (1); and (c) placing the gas‑saturated solid preform (1) in a non‑metallic forming mould and applying microwave radiation to the whole in order to produce softening, expansion and simultaneous forming of the solid preform (1), until a cellular product (6) is obtained. |