Living" radical polymerization of methyl methacrylate was investigated using a new initiating system, i.e. DCDPS/FeCl 3/PPh 3, in which diethyl 2,3 dicyano 2,3 diphenyl succinate(DCDPS) is a hexa substituted etha...Living" radical polymerization of methyl methacrylate was investigated using a new initiating system, i.e. DCDPS/FeCl 3/PPh 3, in which diethyl 2,3 dicyano 2,3 diphenyl succinate(DCDPS) is a hexa substituted ethane thermal iniferter. The polymerization mechanism belongs to a reverse ATRP process. The polymerization was closely controlled in bulk at 75 ℃, polymethyl methacrylate(PMMA) with a high molecular weight and quite narrow polydispersity ( M w/ M n=1 20—1 29) was obtained. End group analysis by 1H NMR spectroscopy shows that the resulting PMMA is ω functionalized by a chlorine atom, which is also confirmed by the chain extension reaction in the presence of CuCl/bipy catalyst via a conventional ATRP process. [WT5HZ]展开更多
文章通过两步反应简单高效地制备出目标多孔有机笼RCC3,将其作为配体和CuBr_(2)配位构建多孔有机笼配合物RCC3@Cu。采用X-射线衍射(X-ray diffraction,XRD)和电喷雾电离质谱(electrospray ionization mass spectrometry,ESI-MS)表征RCC3...文章通过两步反应简单高效地制备出目标多孔有机笼RCC3,将其作为配体和CuBr_(2)配位构建多孔有机笼配合物RCC3@Cu。采用X-射线衍射(X-ray diffraction,XRD)和电喷雾电离质谱(electrospray ionization mass spectrometry,ESI-MS)表征RCC3@Cu的结构与组成,结果表明,RCC3@Cu配位稳定,有望用于介导原子转移自由基聚合(atom transfer radical polymerization,ATRP)。采用RCC3配体介导甲基丙烯酸甲酯(MMA)的ATRP,2 h其转化率达到80%,聚合物分散性指数(polymer dispersity index,PDI)为1.15;最终转化率为98.5%,PDI为1.16。聚合动力学显示RCC3介导的ATRP为近似一级反应动力学,符合活性聚合特征。该文研究RCC3配体介导不同类型单体的聚合,验证了RCC3配体具有单体泛用性。研究结果表明,RCC3体可有效应用于ATRP催化,有进一步研究价值。展开更多
Atom transfer radical copolymerization(ATRP) of styrene(St) and N cyclohexylmaleimide(NCMI) with the CuBr/bpy catalyst in anisole, initiated by 1 phenylethyl bromide(1 PEBr) or tetra (bromomethyl)benzene(TBMB), afford...Atom transfer radical copolymerization(ATRP) of styrene(St) and N cyclohexylmaleimide(NCMI) with the CuBr/bpy catalyst in anisole, initiated by 1 phenylethyl bromide(1 PEBr) or tetra (bromomethyl)benzene(TBMB), afforded well defined copolymer with predetermined molecular weights and low polydispersities, M w/ M n<1.5. Other monomer pairs such as methyl methacrylate(MMA)/NCMI, St/ N phenylmaleimide, MMA/ N phenylmaleimide were studied, too. The influences of several factors, such as temperature, solvent and monomer’s ratio on the copolymerization with the CuBr/bpy catalyst system were subsequently investigated. The apparent activation energy of St(MMA)and NCMI was deduced from the kinetics figure of different temperatures. Using TBMB as the initiator produced four armed star copolymer. The heat resistance of the resultant copolymer has been improved by increasing the NCMI. [WT5HZ]展开更多
文摘Living" radical polymerization of methyl methacrylate was investigated using a new initiating system, i.e. DCDPS/FeCl 3/PPh 3, in which diethyl 2,3 dicyano 2,3 diphenyl succinate(DCDPS) is a hexa substituted ethane thermal iniferter. The polymerization mechanism belongs to a reverse ATRP process. The polymerization was closely controlled in bulk at 75 ℃, polymethyl methacrylate(PMMA) with a high molecular weight and quite narrow polydispersity ( M w/ M n=1 20—1 29) was obtained. End group analysis by 1H NMR spectroscopy shows that the resulting PMMA is ω functionalized by a chlorine atom, which is also confirmed by the chain extension reaction in the presence of CuCl/bipy catalyst via a conventional ATRP process. [WT5HZ]
文摘Atom transfer radical copolymerization(ATRP) of styrene(St) and N cyclohexylmaleimide(NCMI) with the CuBr/bpy catalyst in anisole, initiated by 1 phenylethyl bromide(1 PEBr) or tetra (bromomethyl)benzene(TBMB), afforded well defined copolymer with predetermined molecular weights and low polydispersities, M w/ M n<1.5. Other monomer pairs such as methyl methacrylate(MMA)/NCMI, St/ N phenylmaleimide, MMA/ N phenylmaleimide were studied, too. The influences of several factors, such as temperature, solvent and monomer’s ratio on the copolymerization with the CuBr/bpy catalyst system were subsequently investigated. The apparent activation energy of St(MMA)and NCMI was deduced from the kinetics figure of different temperatures. Using TBMB as the initiator produced four armed star copolymer. The heat resistance of the resultant copolymer has been improved by increasing the NCMI. [WT5HZ]
