锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究Ⅰ丙烯酸酯三元共聚物合成条件对无皂水溶胶性能的影响

三乙醇胺螯合锆烷氧化物;交联反应;锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究 Ⅱ锆螯合物与丙烯酸酯三元共聚物无皂水溶胶的交联反应     

锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究Ⅰ丙烯酸酯三元共聚物合成条件对无皂水溶胶性能的影响

三乙醇胺螯合锆烷氧化物;交联反应;锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究 Ⅱ锆螯合物与丙烯酸酯三元共聚物无皂水溶胶的交联反应     

锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究Ⅱ锆螯合物与丙烯酸酯三元共聚物无皂水溶胶的交联反应

研究了三元丙炮酸酯共聚物（MMA／BA／AA）无皂水溶液中加入三乙醇胺锆螯合物对水溶胶及涂膜性能的影响，在水溶胶中，螯合物增加了共聚物的亲水性，改变了水溶胶的流变性、稳定性、表面张力、螯合物也提高了共聚物涂膜的耐水性，X光电子能谱（XPS）研究表明，在固化成膜过程中螯合物与共聚物发生交联反应，用IR、^1HNMR、DSC、TGA和UV等方法对其交联机理作了初步探讨。     

锆螯合物交联丙烯酸酯共聚物无皂水溶胶的研究Ⅱ锆螯合物与丙烯酸酯三元共聚物无皂水溶胶的交联反应

研究了三元丙烯酸酯共聚物(MMA/BA/AA)无皂水溶胶中加入三乙醇胺锆螯合物对水溶胶及涂膜性能的影响. 在水溶胶中,螯合物增加了共聚物的亲水性,改变了水溶胶的流变性、稳定性、表面张力. 螯合物也提高了共聚物涂膜的耐水性. X光电子能谱(XPS)研究表明,在固化成膜过程中螯合物与共聚物发生交联反应,用IR、1H NMR、DSC、TGA和UV等分析方法对其交联机理作了初步探讨.     

金属离子络合交联丙烯酸酯共聚物无皂水溶胶涂料 Ⅱ.Zn(NH_3)_4~(2 )交联无皂水性涂料的性能

金属离子络合交联丙烯酸酯共聚物无皂水溶胶涂料Ⅱ．Ｚｎ（ＮＨ３）２＋４交联无皂水性涂料的性能杨立群谢志明李卓美＊（中山大学高分子研究所广州５１０２７５）关键词交联丙烯酸酯共聚物，无皂水性涂料，流变性，耐热性，硬度１９９７－０６－１６收稿，１９９７－１２...     

金属离子络合交联丙烯酸酯共聚物无皂水溶胶涂料 Ⅰ.丙烯酸酯共聚物的合成和表征

金属离子络合交联丙烯酸酯共聚物无皂水溶胶涂料Ⅰ．丙烯酸酯共聚物的合成和表征杨立群谢志明李卓美＊（中山大学高分子研究所广州５１０２７５）关键词交联丙烯酸酯共聚物，无皂水溶胶，水性涂料，合成１９９７－０６－１６收稿，１９９８－０１－０８修回广州市科委科技...     

环氧硅烷室温交联丙烯酸酯共聚无皂水溶胶的研究 Ⅰ.环氧硅氧烷微乳液的制备

介绍了丙烯酸酯共聚无皂水溶胶的室温交联剂——环氧硅氧烷(KH-560)的乳化方法。研究了乳化剂类型、用量以及KH-560含量对微乳液性能的影响。结果表明，OP-10具有较好的乳化效果；当ω(OP-10)＝5％、ω(KH-560)＝40％时，微乳液稳定性最佳。微乳液加人无皂水溶胶中制得的交联乳液(用量为5％)室温放置6个月后性能无明显变化，干燥涂膜的交联度达到93％，而且具有较好的耐水、耐溶剂性能(水中溶胀度降低了83％，在甲苯中由原来的溶解变为溶胀115％)。     

丙烯酸酯共聚物无皂水溶胶与金属离子的络合交联

用交联剂M（NH3）42＋（M2＋为Zn2＋、Cu2＋、Ni2＋和Co2＋）络合交联丙烯酸酯无皂水溶胶形成涂膜,用差示量热法和重量分析法考察了涂膜的交联程度,得出一致的结论,均表明交联剂Zn（NH3）42＋的交联效果最佳,适宜的交联固化条件是80℃加热30min;用透射电镜观察到Zn（NH3）42＋与丙烯酸酯水溶胶形成交联网状结构的过程;还用差示扫描量热法初步分析了交联反应的动力学,求出反应级数为3．3,活化能为34．0kJ·mol-1。     

环氧硅烷室温交联丙烯酸酯共聚无皂水溶胶的研究 Ⅰ.环氧硅氧烷微乳液的制备

环氧硅烷室温交联丙烯酸酯共聚无皂水溶胶的研究 Ⅰ.环氧硅氧烷微乳液的制备     

丙烯酸酯共聚物无皂水溶胶流变性能的研究

合成了不含均聚物的丙烯酸酯四元共聚物(MMA/BA/AA/HEMA)。用GPC测定了共聚物的分子量及分子量分布。将共聚物中的羧基中和后制成无皂水溶胶。研究了水溶胶的流变性、表观粘度与剪切速率关系、表观粘度与固含量关系。所得无皂水溶胶涂料具有较优异的性能。     

二氧化碳和丙烯直接合成甲基丙烯酸的NiPMo/TiO2催化剂的研究

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%.     

Toward new camptothecins. Part 6: Synthesis of crucial ketones and their use in Friedländer reaction

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.     

CoFe2O4自形成磁性液体场致结构化对磁化的影响

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.     

Highly regioselective Buchwald–Hartwig amination at C-2 of 2,4-dichloropyridine enabling a novel approach to 2,4-bisanilinopyridine (BAPyd) libraries

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.     

KMnO4-mediated oxidative CN bond cleavage of tertiary amines: Synthesis of amides and sulfonamides

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.     

Chemistry of heterocyclic compounds at the A. E. Favorsky Irkutsk Institute of Chemistry, Siberian Branch of the Russian Academy of Sciences, over 50 years (Review)

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.     

Sulfur-directed metal-free and regiospecific methyl C(sp3)–H imidation of thioanisoles

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.     

Selective syntheses of 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones via temperature-dependent Rh(II)-carbenoid-mediated 2H-azirine-ring expansion

The Rh(II)-catalyzed reaction of 2-carbonyl-substituted 2H-azirines with ethyl 2-cyano-2-diazoacetate or 2-diazo-3,3,3-trifluoropropionate provides an easy access to 2H-1,3-oxazines and 1H-pyrrol-3(2H)-ones. These compounds can be selectively prepared from the same starting material using temperature as the only varied parameter. The 2-azabuta-1,3-diene intermediate, a common precursor for both heterocyclic products, isomerizes into 2H-1,3-oxazine under kinetic control, while 1H-pyrrol-3(2H)-one is the sole product of the reaction at elevated temperatures. According to DFT-calculations a one-atom oxazine ring contraction involving ring-opening to a 2-azabuta-1,3-diene intermediate, followed by a 1,5- and 1,2-prototropic shift leads to the consecutive formation of imidoylketene and azomethine ylide, which then further undergo cyclization to the pyrrole derivative.     

Synthesis of 1-benzyloxypyrazin-2(1H)-one derivatives

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.