功能化嵌段共聚物负载铜配合物的制备及其催化氧化性能

利用可逆-加成-断裂链转移自由基聚合的方法合成3种不同嵌段比的双亲水性嵌段共聚物聚甲基丙烯酸二甲氨乙酯-b-聚甲基丙烯酸酯聚乙二醇单甲醚-b-聚甲基丙烯酸二甲氨乙酯(PDMAEMA-b-POEOMA-b-PDMAEMA),将该共聚物与CuSO4或CuCl2配合,采用FTIR,1H NMR,TG,XRD方法对所得配合物的结构和组成进行表征。表征结果显示,阴离子种类(SO24-或Cl-)对配合物的结构及配位都有一定影响,而共聚物的嵌段比影响配合物的铜含量。采用Cu(Ⅱ)/Polymer-3/SO4配合物(Polymer-3:PDMAEMA39-b-POEOMA11-b-PDMAEMA39)催化苯乙烯氧化反应,在80℃、H2O2为氧化剂、m(苯乙烯)∶m(配合物)=200∶1、6 h的条件下,苯乙烯转化率87.8%,苯甲醛选择性82.1%。该催化剂循环使用3次,催化性能几乎不变。

Synthesis of Functional Block Copolymer Supported Copper Complexes and Their Catalytic Oxidation Behavior

Double hydrophilic block copolymers poly[2-(dimethylamino) ethyl methacrylate]b-poly(oligo(ethylene oxide) monomethyl ether methacrylate)-b-poly[2-(dimethylamino) ethyl methacrylate](PDMAEMA-b-POEOMA-b-PDMAEMA) were synthesized by reversible addition-fragmentation chain-transfer radical polymerization.The copolymer-supported Cu(Ⅱ) complexes were prepared by dropping copper sulfate solution or copper chloride solution into the water solutions of the copolymers.The structure and composition of the Cu(Ⅱ) complexes were characterized by FTIR,1H NMR,TG and XRD.The anions(SO42-and Cl-) had a certain influence on the structure of the complexes,and the block ratio of the copolymers affected copper content in the complexes.Under the reaction conditions for the oxidation of styrene:Cu(Ⅱ)/Polymer-3/ SO4(Polymer-3:PDMAEMA39-b-POEOMA11-b-PDMAEMA39) as the catalyst,H2O2as the oxidant,m(styrene)∶m(complex)=200∶1,80 ℃ and 6 h,the conversion of styrene and the selectivity to benzaldehyde reached 87.8% and 82.1%,respectively.After the catalyst was recycled for three times,its catalytic performance was almost unchanged.