Reversible addition-fragmentation transfer （RAPT） miniemulsion polymerizations for PMMA with cumyl dithiobenzoate （CDB） as a chain transfer agent （CTA） has been carried out. Higher temperature made the polymeriz...Reversible addition-fragmentation transfer （RAPT） miniemulsion polymerizations for PMMA with cumyl dithiobenzoate （CDB） as a chain transfer agent （CTA） has been carried out. Higher temperature made the polymerization much faster and the PDI remained below 1.20, when the temperature was upon 70 ℃.展开更多
The crystal structure of tris-dithiobenzoato-cobalt (Ⅲ) complex Co (S_2CPh)_3 is reported. The Co(Ⅲ) atom is coordinated by six sulfur atoms belonging to three bidentate dithiobenzoato ligands in pseudo-octahedral g...The crystal structure of tris-dithiobenzoato-cobalt (Ⅲ) complex Co (S_2CPh)_3 is reported. The Co(Ⅲ) atom is coordinated by six sulfur atoms belonging to three bidentate dithiobenzoato ligands in pseudo-octahedral geometry. The structure of the molecule possesses approximate C_3v symmetry. Crystal data: Co(S_2CC_6H_5)_3, M_r=518. 64, monoclinic, space group C2/c, a= 13. 233(7), b= 18. 878(8), c= 18. 069(7) A, β=102. 90(3)°, V=4400(3) A￣3, Z=8, D_x=1. 57gcm￣-3, F(000) =2112,μ(MoKα) = 13. 31 cm￣-1 , final R= 0. 037 , R_w= 0. 048 for 2998 reflections.展开更多
Bulk polymerization of styrene was carried out in the presence of a reversible addition fragmentation chain transfer (RAFT) of benzyl dithiobenzoate (BDB). The comparison between reaction systems with and without BDB ...Bulk polymerization of styrene was carried out in the presence of a reversible addition fragmentation chain transfer (RAFT) of benzyl dithiobenzoate (BDB). The comparison between reaction systems with and without BDB indicates that there is significant retardation in the reaction rate when BDB is used. The molecular weight of styrene polymer prepared with BDB shows linear relationship with the conversion of monomer, polydispersity is as narrow as 1.2, and no gel effects are observed during the polymerization with BDB, which are characteristics of a living radical polymerization. It has been found that the concentrations of BDB and azobis (isobutyronitrile) (AIBN) have opposite effects on the polymerization kinetics, and the AIBN dominates.展开更多
文摘Reversible addition-fragmentation transfer （RAPT） miniemulsion polymerizations for PMMA with cumyl dithiobenzoate （CDB） as a chain transfer agent （CTA） has been carried out. Higher temperature made the polymerization much faster and the PDI remained below 1.20, when the temperature was upon 70 ℃.
文摘The crystal structure of tris-dithiobenzoato-cobalt (Ⅲ) complex Co (S_2CPh)_3 is reported. The Co(Ⅲ) atom is coordinated by six sulfur atoms belonging to three bidentate dithiobenzoato ligands in pseudo-octahedral geometry. The structure of the molecule possesses approximate C_3v symmetry. Crystal data: Co(S_2CC_6H_5)_3, M_r=518. 64, monoclinic, space group C2/c, a= 13. 233(7), b= 18. 878(8), c= 18. 069(7) A, β=102. 90(3)°, V=4400(3) A￣3, Z=8, D_x=1. 57gcm￣-3, F(000) =2112,μ(MoKα) = 13. 31 cm￣-1 , final R= 0. 037 , R_w= 0. 048 for 2998 reflections.
文摘Bulk polymerization of styrene was carried out in the presence of a reversible addition fragmentation chain transfer (RAFT) of benzyl dithiobenzoate (BDB). The comparison between reaction systems with and without BDB indicates that there is significant retardation in the reaction rate when BDB is used. The molecular weight of styrene polymer prepared with BDB shows linear relationship with the conversion of monomer, polydispersity is as narrow as 1.2, and no gel effects are observed during the polymerization with BDB, which are characteristics of a living radical polymerization. It has been found that the concentrations of BDB and azobis (isobutyronitrile) (AIBN) have opposite effects on the polymerization kinetics, and the AIBN dominates.
