磷配体结构对铁系催化剂原子转移自由基聚合的影响

Effect of Phosphorus Ligand Structure on Iron Catalyst-based Atom Transfer Radical Polymerization

以三价铁卤化物为催化剂进行原子转移自由基聚合(ATRP),通过过量单体的还原作用促进高价态的铁卤化物还原为可进行ATRP的低价态铁卤化物和含卤素的引发剂,在含磷配体的存在下,催化甲基丙烯酸甲酯和苯乙烯单体的可控聚合,考察磷配体结构对甲基丙烯酸甲酯和苯乙烯聚合的影响。结果表明:得到的聚甲基丙烯酸甲酯和聚苯乙烯凝胶色谱曲线为单峰,分子量分布在1.5以下;可通过对甲基丙烯酸甲酯与苯乙烯进行分段聚合制备聚甲基丙烯酸甲酯与聚苯乙烯的嵌段共聚物。

Atom transfer radical polymerization(ATRP)was carried out by using trivalent iron halide as catalyst.The trivalent iron halide was reduced by monomer to form a low-valent state iron halides and halogen-containing monomer(initiator).In the presence of a phosphorus-containing ligand,the methyl methacrylate and styrene polymerization was carried out.The effect of phosphorus ligands structure on the polymerization of methyl methacrylate(MMA)and styrene(St)was investigated.The results show that the obtained poly(methyl methacrylate)(PMMA)and polystyrene(PS)show a single gel chromatograms peak,and the molecular weight distribution is less than 1.5.The PMMA-block-PS can be prepared through sequence polymerization of methyl methacrylate and styrene.