METHOD FOR PREPARING PEIT COPOLYESTER

• Main Authors: XIE, Xin, TANG, Gen, ZHAO, Yongbin, XU, Hansong, ZHOU, Siwei
• Format: Patent
• Language: Chinese; English; French
• Published: 07.03.2024
• Subjects: CHEMISTRY; COMPOSITIONS BASED THEREON; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP

Disclosed is a method for preparing a polyethylene isosorbide terephthalate (PEIT) copolyester. The method comprises: A) subjecting bis(2-hydroxyethyl) terephthalate (BHET) to a transesterification reaction with isosorbide, to generate ethylene isosorbide terephthalate; B) subjecting excess BHET monomer in the transesterification system to a melt polymerization reaction with the generated ethylene isosorbide terephthalate, to obtain a PEIT copolyester. The present invention not only achieves a high conversion rate and a high-proportion addition of isosorbide, causing the prepared PEIT copolyester to exhibit excellent heat resistance, but also can ensure that the copolyester has a DEG content below 1.2% and a color value (b value) less than 3, fully satisfying the requirements for food packaging applications; in particular, the BHET monomer used may be derived from chemical recycling of waste polyesters, having significant value in achieving resource recovery of waste polyesters. La présente divulgation concer