| 摘要 |
PURPOSE: Provided is a preparation of polybutylene terephthalate(hereinafter, called PBT) resin in which inhibits generation of byproducts by optimizing reaction conditions on injection of 1,4-butanediol and esterification. CONSTITUTION: The esterification in the preparation of PBT is carried out at a temperature of 200- to 250 deg.C and under decompressed pressure from 100mmHg to 700mmHg to decrease a reaction mole ratio of terephthalic acid and 1,4-butanediol to below 1.3. Acid ingredients to be used in the preparation of PBT are 85 to 100 mol% of terephthalic acid or the ester-forming derivatives thereof and 0 to 15mol% of naphthalene dicarbonic acid, isophthalic acid or the esterifiable derivatives thereof. Diol ingredients are mainly 1,4-butanediol (1,4-BD) and 0 to 20mol% of ethylene glycol, propylene glycol, trimethylene glycol, or 1,4-dimethylcyclohexane. |
