Department of Chemical & Biochemical Engineering, Missouri University of Science and Technology , 1101 North State Street, Rolla, Missouri 65409, United States.
Department of Chemistry, Missouri University of Science and Technology , 400 West 11th Street, Rolla, Missouri 65409, United States.
ACS Appl Mater Interfaces. 2017 May 17;9(19):16288-16295. doi: 10.1021/acsami.7b04092. Epub 2017 May 8.
Highly hydrophilic and solvent-stable porous polyamide-imide (PAI) hollow fibers were created by cross-linking of bare PAI hollow fibers with 3-aminopropyl trimethoxysilane (APS). The APS-grafted PAI hollow fibers were then functionalized with salicylic aldehyde for binding catalytically active Pd(II) ions through a covalent postmodification method. The catalytic activity of the composite hollow fiber microfluidic reactors (Pd(II) immobilized APS-grafted PAI hollow fibers) was tested via heterogeneous Heck coupling reaction of aryl halides under both batch and continuous-flow reactions in polar aprotic solvents at high temperature (120 °C) and low operating pressure. X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma (ICP) analyses of the starting and recycled composite hollow fibers indicated that the fibers contain very similar loadings of Pd(II), implying no degree of catalyst leaching from the hollow fibers during reaction. The composite hollow fiber microfluidic reactors showed long-term stability and strong control over the leaching of Pd species.
通过用 3-氨丙基三甲氧基硅烷（APS）交联裸聚酰胺-酰亚胺（PAI）中空纤维，制备了高亲水性和溶剂稳定的多孔聚酰胺-酰亚胺（PAI）中空纤维。然后，用水杨醛对 APS 接枝的 PAI 中空纤维进行功能化，通过共价后修饰方法将催化活性的 Pd（II）离子结合。通过在高温（120°C）和低工作压力下在非质子极性溶剂中进行芳基卤化物的非均相 Heck 偶联反应，测试了复合中空纤维微流反应器（Pd（II）固定在 APS 接枝的 PAI 中空纤维上）的催化活性。对起始和回收的复合中空纤维进行 X 射线光电子能谱（XPS）和电感耦合等离子体（ICP）分析表明，纤维含有非常相似负载量的 Pd（II），这意味着在反应过程中纤维中没有Pd 物种的浸出程度。复合中空纤维微流反应器表现出长期稳定性和对 Pd 物种浸出的有效控制。
