茂金属催化剂分子“剪裁”新型异氰酸酯类聚合物

Molecular-Tailored New Type Polyisocyanates Via Molecular Design of Metallocene Complex

报导了用茂金属催化剂Ｃｐ’ＭＣｌ２Ｌ或Ｃｐ’２ＭＣｌＬ（其中Ｃｐ’＝环戊二烯基或取代环戊二烯基，Ｍ为Ｔｉ、Ｚｒ、Ｈｆ或稀土金属（Ｓｍ）等，Ｌ为Ｈ、ＣＨ３、ＯＲ或Ｎ（ＣＨ３）２、ＣＨ２ＣＦ３等）引发异氰酸酯活性聚合的研究及发展。讨论了催化剂的分子设计，可“剪裁”具有星型、梳型、间断蠕虫链（Ｏｎｃｅ－Ｂｒｏｋｅｎｗｏｒｍｓ）、刚－柔－刚多嵌段及具有光学活性和液晶特性的新型异氰酸酯聚合物。同时还讨论了聚合反应和催化的动力学与链增长机理。

In this review, using metallocene catalysts (e.g. Cp'MCl 2L or Cp' 2MClL (Cp'=cyclopendiene or substituted cyclopendiene; M=Zr、Ti、Hf or rare earth metal; L=H、CH 3、OR or N(CH 3) 2 and CH 2CF 3) , the living polymerization of isocyanates monomers were reported. Many new type structural (e.g. star type、comb type、once broken worms link) and functional polyisocyanates, and random or block isocyanate copolymers with special properties of optical activity and liquid crystal behavior were tailored by molecular design of metallocene catalysts. The polymerization mechanics and reaction kinetics of isocyanates have also been discussed.