稀土复合催化剂对聚酯酯交换和缩聚的影响

Effect of Different Rare Earth Compounds on Polyester Transesterification and Polycondensation

以自制稀土化合物作聚酯酯交换和缩聚复合催化剂,对各工艺参数进行分析,并对产品性能进行测试和表征。结果表明,稀土化合物可作为聚酯酯交换的催化剂和缩聚助催化剂,使用稀土/三氧化二锑复合催化剂,能有效提高反应效率,缩短反应时间,降低酯交换开始温度;分子量和分子量分布优于常规聚酯,且产品色相优于普通三氧化二锑催化所得聚酯,等温结晶规律与常规聚酯类似,但结晶能力有所提高,结晶度和晶粒尺寸比普通三氧化二锑催化所得聚酯高,且有机稀土比无机稀土催化效率更高,催化剂中添加17%的稀土化合物就能获得满意的效果。

Rare earth compounds were used as complexes catalysts for polyester transesterification and polycondensation, and process parameters and properties of the polyester were discussed in detail. The results showed that rare earth compounds were used as associate catalysts for polyester transesterification and polyeondensation. Rare earth coordinative Sb2 03 could en- hance the reaction efficiency, reduce the reaction time and lower initial temperature of transesterification. At the same time, molecular weight and molecular weight distribution of the polyesters surpassed conventional polyesters, the hue value and crys- tallization capabilities of polyester by rare earth compounds - Sb2 03 were better than that of those by stibium compound cata- lysts. Efficiency of polyester catalyzed by organic rare earth compound was better than inorganic rare earth compound. It could gain satisfactory achievement by adding less than 17% rare earth compounds as associate catalysts on polyester prepared.