负载三乙烯二胺纳米反应器的制备及其催化应用  

Preparation and catalytic application of DABCO-functionalized nanoreactor

作　　者：王程展 蔡芳 董旭丽 张利方 陈涛[1] WANG Chengzhan;CAI Fang;DONG Xuli;ZHANG Lifang;CHEN Tao(Key Laboratory of Advanced Textile Materials and Manufacturing Technology,Ministry of Education,Zhejiang Sci-Tech University Hangzhou 310018,China;Zhejiang Cady Industry Co.,Ltd.,Huzhou 313013,China)

机构地区：[1]浙江理工大学先进纺织材料与制备技术教育部重点实验室,杭州310018 [2]浙江彩蝶实业股份有限公司,浙江湖州313013

出　　处：《浙江理工大学学报（自然科学版）》2021年第4期512-519,共8页Journal of Zhejiang Sci-Tech University(Natural Sciences)

基　　金：浙江省重点研发计划项目(2021C01076)。

摘　　要：为制备在含有活泼亚甲基的化合物与醛或酮的缩合(Knoevenagel缩合)反应中具有高催化效率且可多次利用的催化剂,首先通过可逆加成-断裂链转移(RAFT)聚合合成嵌段聚合物,然后通过烷基溴与胺的亲核取代反应在嵌段共聚物的疏水链段负载三乙烯二胺(DABCO),最后使所得功能性两亲嵌段共聚物在水中自组装形成负载DABCO的催化纳米反应器。采用GPC、1HNMR、TEM、DLS等手段表征聚合物和纳米反应器的结构,采用UV-Vis光谱仪和GC-MS分别研究催化剂的回收和催化性能。结果表明:负载DABCO的两亲嵌段共聚物的低临界溶解温度(LCST)随着OEGMA聚合度的增加而增大;负载DABCO的纳米反应器在LCST下呈球形,粒径100 nm左右,在水中具有良好的分散性。负载DABCO的纳米反应器在用量为0.05 mmol、水相室温条件下催化Knoevenagel缩合反应,产率可达到93%以上,使用之后的纳米反应器可通过加热离心沉淀的方法进行回收。该负载DABCO的纳米反应器有效地结合了均相催化剂和异相催化剂的优点,在Knoevenagel缩合反应中既具有较高的催化效率,也可方便地回收再利用。In this study,to fabricate highly efficient and recyclable catalyst for the condensation reaction between compounds containing active methylene and aldehyde or ketone(Knoevenagel condensation),we first synthesized block copolymer through reversible addition-fragmentation chain transfer(RAFT)and then loaded 1,4-diazabicyclooctane triethylenediamine(DABCO)on the hydrophobic chain of segmented copolymer through the nucleophilic substitution reaction between alkyl bromide and amine,and finally the resulting functional amphiphilic segmented copolymers were self-assembled in water and formed a DABCO-functionalized catalytic nanoreactor.The structures of the polymer and nanoreactor were characterized by means of GPC,1HNMR,TEM and DLS,etc.The recycling and catalytic properties of the catalyst were investigated by UV-Vis spectroscopy and GC-MS respectively.The results indicate that the lower critical solution temperature(LCST)of the DABCO-functionalized amphiphilic segmented copolymer increases with the increase of the polymerization degree of OEGMA.The DABCO-functionalized nanoreactor is spherical under LCST,with a particle size of about 100 nm and good dispersion in water.When the Knoevenagel condensation reaction was catalyzed by the DABCO-loaded nanoreactor with a dosage of 0.05 mmol in the aqueous phase at room temperature,the yield can reach more than 93%.The used nanoreactor can be recycled by a heating/centrifugal precipitation procedure.This DABCO-loaded nanoreactor effectively combines the advantages of homogeneous catalyst and heterogeneous catalyst,showing high catalytic efficiency in Knoevenagel condensation reaction and easy recycling and reuse.

关 键 词：甲基丙烯酸溴代乙酯 温敏性两亲嵌段共聚物 纳米反应器 KNOEVENAGEL缩合反应 

分 类 号：O632.2[理学—高分子化学]