The present invention relates to a polyester resin and a preparation method therefor, the polyester resin comprising: a diol repeating unit derived from a diol component; and a dicarboxylic acid repeating unit derived from a dicarboxylic acid component, wherein the content ratio between germanium (Ge), zinc (Zn), and phosphorus (P) is controlled within a specific range. The polyester resin according to the present invention can have excellent basic physical properties and color characteristics.

The present disclosure relates to a high-viscosity PETG or PCTG polymerization reactor and a method for polymerizing PETG or PCTG. The polymerization reactor is provided with two shafts in front and rear, the two shafts are respectively provided with a plurality of disc reactors, and the polymerization reactor is divided into a low viscosity zone, a med-high viscosity zone, and a high viscosity zone; the disc reactors in the high viscosity zone are single discs that can be quickly disassembled; a plurality of scrapers is further arranged on a wall of the polymerization reactor between each two adjacent single discs in the high viscosity zone, the distance between each scraper and the adjacent single disc is different, which can gradually reduce the thickness of the high-viscosity melt on the discs, improve the devolatilization efficiency. The polymerization reactor can prepare PETG or PCTG with high viscosity and excellent hue performance.

The present invention relates to: a polyester resin mixture comprising a polyester copolymer prepared using a recycled monomer; a method for preparing same; and a polyester film prepared thereby, wherein the polyester resin mixture has excellent extrusion properties (processability), and thus can provide a polyester film having excellent physical properties and/or quality.

The present invention relates to a polyester resin and a molded article manufactured therefrom. The polyester resin has a specific viscosity controlled within a specific range, and thus can have excellent processability in an extrusion blow molding process. In particular, even though the polyester resin according to the present invention contains repeat units derived from recycled raw materials, it can have crystallinity and the optimal level of viscosity required for each of the barrel and die of an extrusion blow molding process.