张兴宏副教授在Macromolecules发表论文

题目：Highly Regioselective and Alternating Copolymerization of Racemic Styrene Oxide and Carbon Dioxide via Heterogeneous Double Metal Cyanide Complex Catalyst

作者：Ren-Jian Wei, Xing-Hong Zhang*, Bin-Yang Du, Xue-Ke Sun, Zhi-Qiang Fan, Guo-Rong Qi

Macromolecules 2013, 46, 3693−3697

dx.doi.org/10.1021/ma4004709

“极性”环氧单体与CO₂共聚较为困难，迄今仅有数遍文章报道极性环氧单体与CO₂的全交替共聚。报道的均相催化体系当活性种进攻环氧的次甲基时，易发生偶合反应，而非聚合反应；因此研究者通过精妙的催化剂设计，通过精确调节催化剂骨架的位阻效应和助催化剂结构等，使增长链活性种只进攻亚甲基，从而获得全交替结构，但实际上并未实现区域选择性，说明在“极性”环氧单体与CO₂共聚体系中，增长链活性种依然等概率地进攻了亚甲基和次甲基。我们认为如果不采用助催化剂，体系中只存在增长链活性种，同时其只进攻次甲基的话，那么得到的共聚物应该是高度区域规整性的。实验结果证实了我们的假设。我们采用单组份纳米片状双金属氰化络合物催化剂，实现“极性”环氧单体氧化苯乙烯和CO₂全交替和区域选择性共聚，是对本领域研究的一个好的贡献。

     Supposed that CO₂-SO copolymerization were full alternating, the attack of -COO^- to CH or CH₂ of SO(step (1) or (2)) will determine the regio-selectivity (M is metal ion; :uN is organic base); inserted chart: Typical SEM image of heterogeneous Zn-Co (III) DMCC catalyst, the tetrahedral (CN)₂Zn-OH structure is proposed as the initiating group of this catalyst (CA represents the complexing agent used during the preparation of the catalyst).