Methods for producing polyester films and polyester products, heat-shrinkable polyester films and their products.

Abstract

The invention proposes methods for the fabrication of heat-shrinkable polyester films, wherein the heat-shrinkable polyester film is made from components including recycled material. Such methods include a method for the fabrication of heat-shrinkable polyester films comprising: (a) heating a mixture of terephthalic acid (TPA) or dimethyl terephthalate (DMT), ethylene glycol (EG), the modifying component and the recycled material, to a temperature of approximately 230°C to approximately 280°C to undergo esterification and produce the esterified product; (b) passing the esterified product through a filter with a pore size of approximately 5 μm to approximately 20 μm and at a pressure differential per hour of less than approximately 0.1 bar per hour; (c) heating the esterified product in the presence of a catalyst and a heat stabilizer to undergo polymerization and produce the polyester product; (d) processing polyester products to produce polyester resin; (e) extruding polyester resin to produce sheets; and (f) feeding sheets into a film-forming process to produce heat-shrinkable polyester film.

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