稀土催化体系催化PET固相缩聚的研究

Solid-State Polycondensation of PET Catalyzed by Rare Earth Compound

研究了稀土催化体系对聚对苯二甲酸乙二酯固相缩聚反应的催化效果及对所得高分子量聚酯切片性能的影响。发现稀土催化体系可明显提高聚酯固相缩聚的反应速率。稀土催化体系对聚酯固相缩聚反应的催化活性明显高于传统催化体系 ,其中单一稀土催化体系与混合稀土催化体系在较低温度下具有相近的催化活性 ,而在较高温度下单一稀土催化体系的催化活性较高 ;加入稳定剂 ,不影响稀土催化的固相缩聚反应速率 ;稀土催化固相缩聚得到的PET样品具有较高的结晶度和较大的晶粒尺寸。其中单一稀土催化所得样品的晶粒尺寸最大 ,相应地 ,单一稀土催化的固相缩聚反应活化能也最大 ;稀土催化体系催化聚酯固相缩聚反应时添加适当稳定剂 ,可获得与采用传统催化体系得到的PET切片相近的热稳定性。

The catalytic effects of rare earth on solid state polycondensation (SSP) of polyethylene terephthelate (PET) were studied. The properties of the high molecular weight PET from the reaction were also studied. Some conclusions are as follows: the reaction of SSP is accelerated more remarkably with addition of rare earth catalyst than that of traditional catalyst. The catalytic ability of pure rare earth system is similar to mixed rare earth system at lower temperature, but the catalytic ability of pure rare earth system is higher than mixed rare earth system at higher temperature. The reaction speed of SSP is not effected with addition of stabilizing agent. The PET from SSR with rare earth has higher crystallinity and larger crystal grain dimension, expecialy the crystal grain dimension and the active energy is the largest for SSP with pure rare earth system. The thermal stability of PET from SSR with little stabilizing agent and pure rare earth system is similar to one of PET from SSR with traditional system.