METHOD FOR THE DIRECT PRODUCTION OF POLYESTER ARTICLES FOR PACKAGING PURPOSES AND ARTICLES OBTAINED THEREFROM

摘要

The present invention is related to a method for the direct production of polyester articles for packaging purposes, in particular for the production of hollow bodies, thermoformed sheets and films, said articles containing an amount of acetaldehyde less than 10 ppm. This method is characterised in tha t it essentially comprises a step in which the initial level SE0 of the sum of end groups in the polymer melt is increased by adding a mixture of at least one inert and at least one reactive substance to said polymer melt to a seco nd level SE1 and a degassing step consisting in essentially applying a vacuum t o the previously obtained polymer melt to cause a removal of low molecular weight substances present and formed, of non reacted reactive substance(s) a nd inert substance(s) added during previous step before the so obtained polymer melt is directly converted into the desired articles.