Various novel double metal cyanide （DMC） catalysts were successfully prepared by modifying the central metal （M） and one of cyanide ion （CN-） in Zna[M（CN）b]c complex. Such modifications have significant impact...Various novel double metal cyanide （DMC） catalysts were successfully prepared by modifying the central metal （M） and one of cyanide ion （CN-） in Zna[M（CN）b]c complex. Such modifications have significant impact on the catalytic efficiency as well as the polymer selectivity for the reaction of PO/CO2. Zn-Ni（Ⅱ） DMC is a potential catalyst for alternating copolymerization of PO/CO2,and DMC catalysts based on Zn3[Co（CN）5X]2 （X = Br^- and N3^-） exhibit moderate efficiency for the production of polycarbonates.This research presents the preliminary exploration of novel DMC complex via chemical modification of its central metal and ligand.展开更多
Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H...Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H-1-NMR analysis shows that the EO content in the copolymer is the same as that in the initial monomer feed. Moderate molecular weight copolymers with various EO content were obtained and their values of molecular weight distribution (MWD) fell in the range of 1.21-1.55. It was found that the molecular weight of copolymers is controlled by the mass ratio of EO+PO to initiator moles used, The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition.展开更多
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)...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.展开更多
基金the National Natural Science Foundation of China(No.50273031)China Postdoctoral Science Foundation(No.20060400339).
文摘Various novel double metal cyanide （DMC） catalysts were successfully prepared by modifying the central metal （M） and one of cyanide ion （CN-） in Zna[M（CN）b]c complex. Such modifications have significant impact on the catalytic efficiency as well as the polymer selectivity for the reaction of PO/CO2. Zn-Ni（Ⅱ） DMC is a potential catalyst for alternating copolymerization of PO/CO2,and DMC catalysts based on Zn3[Co（CN）5X]2 （X = Br^- and N3^-） exhibit moderate efficiency for the production of polycarbonates.This research presents the preliminary exploration of novel DMC complex via chemical modification of its central metal and ligand.
文摘Copolymerization of propylene oxide (PO) and ethylene oxide (EO) using double metal cyanide (DMC) complex as the catalyst was carried out. The structure of random copolymers was confirmed by C-13-NMR and IR spectra. H-1-NMR analysis shows that the EO content in the copolymer is the same as that in the initial monomer feed. Moderate molecular weight copolymers with various EO content were obtained and their values of molecular weight distribution (MWD) fell in the range of 1.21-1.55. It was found that the molecular weight of copolymers is controlled by the mass ratio of EO+PO to initiator moles used, The reaction rate as well as polymer yield decrease with increasing EO content in the feed composition.
文摘报道了锌-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.
基金supported by the National Natural Science Foundation of China(20274053)the Natural Science Foundation of Guangdong Province(9151065004000005)the Scientific and Technical Foundation of Foshan(2014GA000425,2014AG10007)~~
