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《高分子化学》课程是五大化学基础课程(无机化学、有机化学、分析化学、物理化学、高分子化学)之一,是化学类、高分子材料与工程、材料化学专业的必修课程。"活性"/可控自由基聚合是一种相对较新且重要的聚合物合成技术和方法,针对目前《高分子化学》课程中活性自由基聚合的教学比较薄弱的现状,从教学的角度探讨了活性聚合和可控/"活性"自由基聚合的本质和特点,介绍了本人在这方面的教学实践活动,遵循成果导向教育理念,通过以学为中心的教学方式,打造金课,提高教学质量。 相似文献
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为提高本科学生的创新创业能力,通过高分子化学实验教学使学生深入了解仿生共聚物的制备及性能的相关知识,设计了综合探究性实验。通过原子转移自由基聚合法制备仿生共聚物,并将其修饰在多种材料表面。采用X射线光电子能谱、扫描电子显微镜、生物显微镜分别对修饰材料进行表征。该实验通过共聚物的制备使学生掌握高分子化学中活性可控自由基聚合制备共聚物的方法;掌握仿生共聚物设计及构筑方法;使学生学习科研仪器的操作方法,切实提高学生的实践能力。该实验重复性好、创新性及拓展性强,将共聚物设计制备及应用有机结合,适用于高分子专业本科生综合探究性实验。 相似文献
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《高分子化学》课程是大部分材料类专业的必修课程,学生的学习兴趣和对课程内容的掌握程度,对后续的专业课学习影响很大。针对材料类专业《高分子化学》课程教学过程中的一些共性问题,如课程的重点与教学安排、课程主线及其所解决的问题、可控/"活性"自由基聚合的本质和对高分子学科发展的意义、配位聚合的内涵和教学重点以及经典高分子化学与高分子化学新发展之间的关系等,提出了了本人的见解,并就如何调动学生的学习积极性和提高教学质量介绍了本人的教学经验和进行了讨论。 相似文献
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对《高分子化学》课程中若干难点的教学体会 总被引:1,自引:0,他引:1
针对《高分子化学》课程教学中的一些疑难问题,如丙烯的聚合能力、自由基聚合终止反应动力学方程中的系数、从聚合度分布函数推导平均聚合度、缩聚反应中“摩尔系数”的定义和可控活性聚合等,介绍了本人的理解和教学经验。 相似文献
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针对目前<高分子化学>课程中对活性聚合和可控/"活性"聚合的教学比较薄弱的现状,从教学的角度探讨了活性聚合和可控/"活性"聚合的本质和特点,介绍了本人的理解和教学经验. 相似文献
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甲基丙烯酸丁酯的反向ATRP“活性”/可控自由基聚合研究 总被引:2,自引:0,他引:2
自由基聚合以其可聚合的单体种类多、反应条件温和易控制、实现工业化生产容易等优点一直在高分子合成领域占有重要地位,而实现自由基“活性”/可控聚合更是高分子化学工作者孜孜以求的目标之一.然而由于自由基非常活泼,在反应过程中极易发生偶和、歧化终止和链转移等副反应,使自由基活性聚合的实现变得非常困难.1995年Matyjaszewski等[1]提出的原子转移自由基聚合(Atom transfer radical polymerization,ATRP)的概念为自由基活性聚合研究开辟了一条崭新的途径.ATRP反应过程如反应式1所示 相似文献
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用溶胶-凝胶法以磷钼酸(MPA)的镍盐溶液水解钛酸四丁酯制备了NiPMo/TiO2催化剂.使用ICP、 XRD、 TG-DTA、 IR、 TPD-MS和微反应技术研究了催化剂的化学组成、热稳定性、化学吸附性质和催化反应性能.杂多钼酸盐与TiO2通过O2-在TiO2表面发生了键合.在623 K下,杂多阴离子仍保持原有的Keggin结构.CO2在Lewis酸位Ni(Ⅱ)和Lewis碱位Ni-O-Mo的桥氧协同作用下生成CO2卧式吸附态Ni(Ⅱ)←O-(CO)←(O--Ni).丙烯有多种吸附态在催化剂上吸附.在563 K、 1 MPa和空速1500 h-1的反应条件下,丙烯的摩尔转化率为3.2%,产物MAA选择性为95%. 相似文献
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Different approaches for the synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives from simple amino acids have been investigated. A library of 33 precursors for the preparation of N-hydroxy pyrazinones was obtained in moderate to good yields. 相似文献
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Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction
Laurent Gavara Thomas Boisse Jean-Pierre Hénichart Adam Daïch Philippe Gautret 《Tetrahedron》2010,66(38):7544-5571
In the context of the preparation of camptothecin and luotonin A analogs, the synthesis of some key keto-precursors and their use in Friedländer condensation are described. This paper also focuses on the stability of these keto intermediates and emphasizes the major differences between indolizinones and pyrroloquinazolinones series. Noteworthy is also the report of some original structures isolated as by-products of some experiments. 相似文献
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The Langevin paramagnetic theory can’t describe the relation between magnetization of ferrofluids and applied magnetic field. The structuralization of ferrofluids, which is considered the main influence factor of the magnetization, is regarded. The part of magnetization works is deposited when the structure is forming. This action influences the magnetization of ferrofluids directly or indirectly. On the base of the “compressing” model, the Langevin function that usually describes the magnetization of ferrofluid is modified, and a well-fitted curve is obtained. An equation of the relation between the equivalent volume fraction after being “compressed” and the intensity of magnetic field is discovered, which approximately describes the process of magnetization. The relation between the approximate initial susceptibility and the volume fraction can be obtained from modified formula. 相似文献
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Rebecca J. Burton Mandy L. CrowtherNeal J. Fazakerley Shaun M. FilleryBarry M. Hayter Jason G. KettleCaroline A. McMillan Paula PerkinsPeter Robins Peter M. SmithEmma J. Williams Gail L. Wrigley 《Tetrahedron letters》2013
The highly regioselective Buchwald–Hartwig amination at C-2 of the cheap and readily accessible reagent, 2,4-dichloropyridine with a range of anilines and heterocyclic amines is described. This new methodology is robust and provides a facile access to 4-chloro-N-phenylpyridin-2-amines on 0.25 mol scale. These intermediates undergo a further Buchwald–Hartwig amination at higher temperature to enable rapid exploration of the chemical space at C-4 and to provide a library of 2,4-bisaminopyridines. 相似文献
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KMnO4-mediated oxidative CN bond cleavage of tertiary amines producing secondary amine was introduced, which was trapped by electrophiles (acyl chloride and sulfonyl chloride) to form amides and sulfonamides. The reaction could take place at mild condition, tolerating a wide range of function groups and affording products in moderate to excellent yields. 相似文献
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N. A. Nedolya 《Chemistry of Heterocyclic Compounds》2008,44(10):1165-1219
The review contains a concise historical account and information on the most significant researches undertaken by the staff
at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences on the Chemistry
of Heterocyclic Compounds.
Dedicated to Academician of the Russian Academy of Sciences B. A. Trofimov on his 70th jubilee.
Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 10, pp. 1443–1502, October, 2008. 相似文献
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A general synthesis of previously unknown semicarbazone-based α-amidoalkylating reagents, 4-(tosylmethyl)semicarbazones, has been developed. The synthesis involved three-component condensation of semicarbazones of aliphatic or aromatic aldehydes with the same or other aldehydes and p-toluenesulfinic acid. The scope and limitations of this reaction were investigated. The compounds obtained were demonstrated to be an efficient α-(4-semicarbazono)alkylating agents. They were reacted with H- (sodium borohydride), O- (sodium methylate), S- (sodium phenylthiolate), N- (pyrrolidine, sodium succinimide), P- (trialkyl phosphites), and C-nucleophiles (sodium diethyl malonate) to give the corresponding products of the tosyl group substitution, 4-substituted semicarbazones, including analogues of nitrofurazone. Among the prepared compounds tested in vitro for antibacterial and antifungal activity, three nitrofuryl-containing semicarbazones exhibited high biological activities with minimum inhibitory concentration (MIC) values of 8–32 μg/mL. 相似文献
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Regiospecific and direct imidation of the methyl C(sp3)–H bond of thioanisoles is realized under mild and metal-free conditions with N-fluorobis(benzenesulfonyl)imide as an oxidant and nitrogen source. Proposed mechanism suggests that thionium ion intermediates and a Pummerer-type reaction are involved. The imidation has advantages such as high step-economy, excellent functionality tolerance, and regiospecificity, giving structurally diverse imidation products. 相似文献
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A small library of new chiral bidentate hydroxyalkyl-imidazolium salts 1 is conveniently synthesized on multi-gram scale from inexpensive and commercially available chiral pool amino acids. The corresponding carbenes, generated by deprotonation of imidazolium salts 1, in combination with palladium(II) chloride were tested in the Mizoroki–Heck coupling reaction. The most significant results in terms of yields and reactivities were achieved with low catalyst loading. The catalytic activities of these imidazolium salts were also investigated in the asymmetric addition of diethylzinc to benzaldehyde. The use of MgO nanoparticles as an additive in conjunction with these ligands played a crucial role in increasing the efficiency of these reactions. 相似文献