▎ 摘　　要

NOVELTY - Esterification of purified terephthalic acid (PTA) and 1,4-butanediol (BDO), comprises adding terephthalic acid, 1,4-butanediol and polymerization degree catalyst into a reaction kettle, where the adding amount of the polymerization degree catalyst is 0.5-5 wt.% of the mass of terephthalic acid, introducing nitrogen into the reaction kettle to replace vacuum, repeating process for 1-2 times, and reacting at 120-220degrees Celsius and pressure of less than or equal to 101 kPa for 1.5-3.5 hours. USE - The esterification of PTA and BDO is useful for producing polybutylene adipate terephthalate (PBAT). ADVANTAGE - The method: performs esterification of PTA and BDO by selecting a specific polymerization degree catalyst and divides the process into three stages feeding and reaction under optimized reaction conditions; produces oligomer molecular PBT prepolymer with large polymerization degree and large distribution concentration; requires mild reaction conditions; and is easy to control.