Research of synthsis of polytrimethylene terephthalate

In the study, Polytirmehtylene Terephthalate(PTT) is synthesized by means of the transesterification and polycondensation using dimethyl terephthalate(DMT) and 1,3-propanedio(PDO)as material. The analysis of transesterification kinetics shows that the transesterification obeys a second-order reaction kinetics model when the transform ratio is under 95%. Using traditional catalyst system, the experiment results show that when the proportion of n(PDO)/n(DMT) is 2.2/1, the dosage of (AcO)_2Zn between 400～600 μg, reaction temperature at 220 ℃,the transesterification is faster while when the dosage of Sb_2O_3 about 500 μg, reaction temperature at 265 ℃, under high vacuum, the molecular mass of PTT is much better.