| 摘要 |
The invention relates to a method for producing a polyester hollow body or its preform with a reduced acetaldehyde content from a drop-shaped, globular or spherical polyester granulate with a granulate diameter of less than 2 mm. Said method is characterised in that the molecular weight of the polyester in the production step of melt-phase polymerisation is set to an intrinsic viscosity (IV) value of 0.15 to 0.4 dl/g, the melt is transferred to a drop-shaped, globular or spherical mould by drop-processing and subsequently solidifies, the molecular weight of the polyester in the production step of solid-phase polycondensation is increased to an IV value of greater than 0.65 dl/g and the polyester material that has been treated in this manner is shaped by being introduced into shaping means, to form the hollow body or its preform. The shaping process can be carried out by injection moulding, sintering or extrusion blow moulding. The invention also relates to a polyester material for the production of a polyester hollow body or its preform with a reduced acetaldehyde content, in addition to a polyester hollow body or its preform with a reduced acetaldehyde content. |
