关键词: 两性离子催化剂, 烯烃聚合, 茂金属配合物, 非茂金属配合物

Abstract: By their structural features，zwitterionic catalysts can be divided into metallocene and non-metallocene (early and late transition metal) complexes. According to the location of counterions in the molecule structure，zwitterionic metallocenes can be classified into girdle-，bridge- and ring-type families. Extensive data on the synthesis，structural characteristics and catalytic activity of the zwitterionic systems for olefin polymerization are reviewed. While zwitterionic catalysts exhibit good activity in respect to olefin polymerization，non-metallocene catalysts possess certain activity in reactions of small molecules as well. Research on these potential single-component catalysts for olefin polymerization and other processes (especially in part concerning small molecule activation) is still required.

Key words: zwitterionic catalyst, olefin polymerization, metallocene, non-metallocene