PET的固相聚合

利用固定床反应器研究聚对苯二甲酸乙二酯（ＰＥＴ）预聚体颗粒在Ｎ２流场中的固相聚合，探讨了聚合温度和Ｎ２流速对聚合反应速率的影响，实验中解决了高温聚合时物料的粘结问题；利用ＤＳＣ分析固相聚合过程中聚合物结晶结构的变化；建立了动力学模型描述了小分子不稳定扩散和化学反应速率共同控制下的聚合反应历程；计算结果较好的反映了工艺操作条件对固相聚合反应的影响。

SOLID STATE POLYCONDENSATION OF POLYETHYLENE TEREPHTHALATE

solid state polycondensation of poly(ethylene terephthalate )was carried out on the low molecular weight ptcpolymer in a stream of dry nitrogcn. The effects of reaction temperature and flow rate of gas on SSP were studied.A better technology is set up.The best way to avoid sticking is to polymerize prepolymer at the temperature below the sticking point for a period of time. After this process the reaction is performed at a higher temperature. DSC thermal analysis indicates that the crystals turn to better lattice during the SSP. A new kinetic model is developed for the SSP process which is controlled by a reversible chemical reaction and the physical diffusion of the condensation by-products.The model results explain the influence of inert gas and temperature on the SSP.