锌-钴双金属氰化络合物催化二硫化碳与氧化环己烯共聚研究

COPOLYMERIZATION OF CARBON DISULFIDE AND CYCLOHEXENE OXIDE WITH A DOUBLE-METAL CYANIDE COMPLEX CATALYST

报道了锌-钴双金属氰化络合物(double metal cyanide complex,DMCC)催化CS2与氧化环己烯(CHO)直接共聚生成脂环族聚硫代碳酸酯的反应.傅立叶红外光谱(FTIR)及拉曼(Raman)光谱结果表明该共聚物端基为-OH和-SH结构;核磁共振(1H和13C-NMR)结果表明共聚物主链含碳酸酯-O(CO)O-链节和4种硫代碳酸酯-O(CO)S-、-S(CO)S-、-O(CS)S-和-S(CS)S-链节结构;气相色谱-质谱(GC-MS)联用结果表明产物中含有环硫环己烷及3种环状硫代碳酸酯.聚合物链结构和产物种类表明CS2/CHO共聚反应存在氧-硫原子交换反应过程.

A novel alicyclic polythiocarbonate with a complex structure sequence has been synthesized by a convenient one-pot polymerization of carbon disulfide （CS2） and cyclohexene oxide （CHO） with Zn-Co^Ⅲ doublemetal cyanide complex （DMCC） as the catalyst. The catalytic activity of the Zn-Co^Ⅲ DMCC could reach to 445 g polymer/g catalyst when the reaction temperature was 100℃ and molar ratio of CHO/CS2 was 2. Further increasing or decreasing the temperature resulted in a decrease in the catalytic activity. The weight-average molecular weight （Mw ） of the obtained eopolymer was in the range of 1.1 × 10^3 -1.3× 10^3 with a molecular weight distribution （MWD） of 1.57 - 1.71 .The copolymer has terminated --OH and-SH groups from the results of FTIR spectrum and Raman spectrum. Furthermore, one carbonate unit -O （O）CO-, and four thiocarbonate units -S（O）-CO-,- S（O） CS-,-S（S） CO-, and -S（S） CS- in the copolymer were found from l H and 13 C-NMR spectra, and the monothiocarbonate unit （-S（O）CO-） was the main unit in the eopolymer,whieh was consistent with the results from FFIR spectrum. Cyclohexene sulfide, which was a direct evidence for O-S atom-exchange reaction, was detected by GC-MS technique from the products. Only hexahydro-benzo[ 1,3] oxathiol-2-one, hexahydro-benzo [ 1,3 ] dithiol-2-one, and hexahydro-benzo [ 1,3 ] dithiole-2-thione （ theoretically six five-membered cyclic products） were detected due to the monomer structural factors and tbermodynamical factors. The eopolymer chain structure and variety of cyclic products indicates that an O-S atom-exchange reaction existed in the copolymerization. Further efforts and experiments are on going in order to further explore the mechanism of the atom-exchange copolymerization and with a view to synthesizing a sulfur-containing polymer with high molecular weights, controllable stereochemical structures, as well as high catalytic activity.