三氟甲磺酸稀土催化ε-己内酯开环聚合

Ring-opening Polymerization of ε-Caprolactone Catalyzed by Rare Earth Trifluoromethanesulfonate [Ln(OTf)_3] Catalysts

采用三氟甲磺酸稀土(镧、钕、铒)作为单组分催化剂催化了ε-己内酯的本体开环聚合反应.考察了稀土元素种类、催化剂浓度、聚合时间及温度对单体转化率和聚合产物分子量的影响.该类催化剂在催化聚合过程中具有单一活性中心,且催化活性较高.此聚合反应可能是通过阳离子活性末端链聚合机理进行的.

The ring-opening polymerization of ε-caprolactone （CL） catalyzed by rare earth trifluoromethane- sulfonate [ Ln（ OTf）3 ] （Ln = Nd, Er, La） catalysts was reported. The influences of rare earth element, cata-lyst concentration, polymerization time and temperature on the monomer conversion and polymer molecule weight were investigated. These catalysts exhibit a high catalytic activity with single active center. The polymerization may proceed via active chain end cationic machanism.