氮修饰的介孔高分子材料的合成及其应用

发布时间：2018-04-04 02:23

本文选题：氮修饰高分子材料　切入点：有序介孔结构　出处：《上海师范大学》2017年硕士论文

【摘要】：随着科学的发展和科技的进步,人们对环境问题日益关注,目前人类正在面临非常严重的资源和环境危机,日益恶化的环境使化学家们不得不考虑减少化学对环境造成的危害。绿色化学的概念应运而生,要考虑如何处理化工行业产生的各种有毒废物,更主要的是,在源头加以解决,即选择可再生无污染的底物,设计合理的反应条件和催化剂,减少不必要副产品的出现,同时,也可以将均相催化剂固载化,可以通过简单方式将催化剂回收循环利用。人们在生产和生活方面对具有新型功能的聚合材料的需求,以及科技水平的进步,近年来人们开发了众多的有着特殊物理化学性质和功能的高分子材料,其性能和特征大大超出了传统高分子材料的范畴。尤其是功能化介孔高分子材料受到了广大科学界学者的极大关注,其物理、化学、生物、医药、环境、材料等领域正发生在巨大变革。如何实现高分子材料功能化,实现工业化生产又是科学家面临的巨大挑战。一方面,介孔高分子材料所具有的大比表面积、有序孔结构使得催化活性组分能够均匀分散在载体表面;另一方面,采用化学稳定性好的介孔聚合物材料将不会破坏活性组分的化学微环境,相反,载体提供的相对惰性的化学微环境将对催化活性组分起到一定保护作用。而酚醛树脂有大量的酚羟基,有利于吸附金属离子,短孔道的纳米小球具有快速吸附平衡的能力,丰富的苯环结构使电子分布不均匀,从而增大材料的吸附量。在制备固载型催化剂时,采用后嫁接法常常会由于有机基团堵塞孔道而导致催化活性的降低;而采用原位共聚法制备非均相催化剂时,由于有机基团共聚到载体骨架中,可使得活性位高度分散,不易造成孔道的堵塞。同时由于高分子本身具有很强的韧性,通过简单的浸渍法可以将金属离子给负载到酚醛树脂上去。基于这一思路,本论文主要通过水热方法制备了不同功能化的介孔高分子材料,并考察了他们在水相或无溶剂的有机反应如Knoevenagel反应和Henry反应中的催化活性,以及负载金属后的催化剂在Suzuki偶联反应和Barbier反应的催化活性,主要分为以下三部分:第一部分,采用3-羟基吡啶和苯酚、甲醛作为原料,以非离子型表面活性剂EO-PO聚醚型F127作为结构导向剂,通过水热合成的方法得到氮修饰的功能化的纳米小球(3HP-MPNs)。该材料具有较短的有序直孔道和规整的形貌,有助于分子和产物分子的传质和扩散,并通过骨架上的碱性活性位点和苯酚的特殊空间取向进行协同催化,进行水介质的Knoevenagel反应。第二部分,采用2-羟基-5-硝基吡啶和苯酚、甲醛作为原料,以F127作为结构导向剂,通过水热合成的方法得到氮修饰的功能化的有序直孔道和规整的形貌的纳米小球(2HP-5NG-MPNs),该材料有助于分子和产物分子的传质和扩散的特点。并利用其高温煅烧后形成的氨基催化无溶剂的Henry反应。第三部分,利用水热法合成了高度有序的氮修饰的功能化的介孔酚醛树脂,然后通过浸渍法合成负载型金属(主要是Pd)纳米催化剂,基于该催化剂高分子载体的抗碱性及纳米粒子的高度均一分散,应用于Suzuki偶联反应和Barbier反应,尝试将第二部分制得材料与其他金属进行结合,并测其反应活性。总之,论文的主要目标围绕发展氮功能化介孔酚醛树脂合成技术,优化制备工艺和条件(反应温度、浓度、原料组成和时间),并通过应用揭示材料的孔道形态,立体形貌,以及活性位分布对性能的影响。通过观察材料学发展史,发现酚醛树脂是在催化领域中被广泛使用的材料之一。因此,结构和组分可控的功能化介孔酚醛树脂有着广泛的应用前景。
[Abstract]:With the development of science and technology, people are increasingly concerned about environmental issues, the mankind is facing very serious resource and environmental crisis, the deteriorating environment enables chemists to consider reducing the harm to the environment caused by chemical. The concept of green chemistry should be born, to consider how to deal with all kinds of toxic waste chemical industry the more important is to solve the problems in the source, choose renewable substrate, reaction conditions and catalyst design, reduce unnecessary by-products, at the same time, can also be immobilization of homogeneous catalyst by simple way catalyst recycling. Demand for polymers the new function in the aspects of production and life, and the progress of science and technology level in recent years, people developed many have special physical and chemical properties and function of high Molecular materials, its performance and features greatly beyond the traditional polymer category. Especially functionalized mesoporous polymer materials have attracted great attention, the majority of the scientific community of scholars in the physical, chemical, biological, pharmaceutical, environmental, materials and other fields are in great changes. How to achieve functional polymer materials, industrialized production it is a huge challenge for scientists. On the one hand, the mesoporous polymer material with high specific surface area, pore structure of the catalysts can be uniformly dispersed on the surface of the carrier; on the other hand, using mesoporous polymer material with good chemical stability will not destroy the chemical active components of the micro environment, on the contrary, the relative chemical inert carrier provides the microenvironment of the catalytic active components play a protective role. And phenolic resin phenolic hydroxyl number, is conducive to the adsorption of metal ions, short channel The nano ball has ability of fast adsorption, benzene ring structure rich electronic distribution is not uniform, so as to increase the adsorption capacity of materials. In the preparation of supported catalysts, often lower catalytic activity due to the blockage of the mesopore by grafting method; and by in situ copolymerization prepared by heterogeneous catalyst when the organic group copolymerized with vector backbone, the activity of a highly dispersed, not easy to cause pore blockage. At the same time as the polymer itself has a strong toughness, by the impregnation method can be simple to load metal ions into the phenolic resin. Based on this idea, this paper mainly by hydrothermal method the preparation of mesoporous materials with different functional polymer, and studied them in aqueous or organic solvent free reactions such as catalytic activity of Knoevenagel reaction and Henry reaction, and the load of gold The catalytic activity of the catalyst is in Suzuki coupling reaction and Barbier reaction, mainly divided into the following three parts: the first part, using 3- hydroxy pyridine and phenol and formaldehyde as raw materials, using nonionic surfactant EO-PO polyether type F127 as structure directing agent, nitrogen modified functionalized nanoparticles by the method of water thermal synthesis (3HP-MPNs). The morphology of the material has short straight channel orderly and regular, contribute to the molecular and molecular mass transfer and diffusion, and through the special space framework on the alkaline active site and phenol in orientation of synergistic catalysis, Knoevenagel reaction in aqueous medium. In the second part, using 2- -5- hydroxy nitro pyridine and phenol and formaldehyde as raw material, using F127 as the structure directing agent, nano ball nitrogen modified functional morphology of ordered straight channels and regular by hydrothermal method (2 HP-5NG-MPNs), the characteristics of the materials contribute to the molecular and molecular mass transfer and diffusion. The Henry reaction and the catalytic amino formed after high-temperature calcination without solvent. In the third part, nitrogen modified highly ordered hydrothermally synthesized functionalized mesoporous phenolic resin prepared by impregnation method, and then load type of metal (Pd) catalysts, the catalyst dispersed polymer carrier anti alkaline and highly homogeneous nanoparticles based on Application in Suzuki coupling reaction and Barbier reaction, try to second parts of prepared materials and other metal binding, and test its reactivity. In short, the main goal of the paper around the development of synthetic technology of nitrogen functionalized mesoporous phenolic resin, process optimization and preparation conditions (reaction temperature, concentration, composition of raw materials and time), and through the application of revealing the material pore morphology, vertical shape, and activity The influence of bit distribution on properties is studied. By observing the development history of materials, it is found that phenolic resin is one of the materials widely used in catalysis field. Therefore, functionalized mesoporous phenolic resin with controllable structure and composition has wide application prospects.

【学位授予单位】：上海师范大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TB383.4;O643.36

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