沉淀聚合法Poly(DVB-co-EGDMA-co-MAA)功能聚合物微球的制备及表征

采用二乙烯基苯-55(DVB-55)和乙二醇二甲基丙烯酸酯(EGDMA)作为混合交联剂,乙腈为溶剂,偶氮二异丁腈(AIBN)为引发剂,以甲基丙烯酸为功能单体采用沉淀聚合法合成了单分散或窄分散的、表面具有羧基的交联聚合物微球,所得微球的粒径变化范围为0.6～3.8μm.通过调节交联剂DVB-55和EGDMA的投料比,可以对微球的粒径、粒径分布、产率、热稳定性以及表面官能团含量进行有效控制.文中对混合交联剂DVB-55与EGDMA比例的改变对微球的粒径、粒径分布以及产率的影响机理给出了理论解释;对DVB和EGDMA的兼容性研究表明,制备的三元聚合物微球的核拥有比投料比稍多的DVB单元,而微球的外层则以在预聚混合物中占更大比例的交联剂为主.     

沉淀聚合法制备窄分散聚(甲基丙烯酸缩水甘油酯-co-乙二醇二甲基丙烯酸酯)功能聚合物微球

以偶氮二异丁腈(AIBN)为引发剂,甲基丙烯酸缩水甘油酯(GMA)和乙二醇二甲基丙烯酸酯(EGDMA)为共聚单体,采用沉淀聚合法制备了不同交联度的窄分散聚合物微球,考察了共聚单体对聚合物微球粒度、分散性以及产率的影响,并用扫描电镜(SEM)和红外光谱对微球进行了表征,SEM结果显示当EGDMA的比例在40mol%～70mol%之间时,可得到单分散的poly-(GMA-co-EGDMA)微球.     

蒸馏沉淀聚合过程中交联度对单分散聚合物微球形成的影响书

以苯乙烯为单体、二乙烯基苯（DVB）为交联剂，过氧化二苯甲酰（BPO）为引发剂研究了蒸馏沉淀聚合法制备聚合物微球过程中交联单体二乙烯苯的用量对单分散聚合物微球成球的影响。结果表明，增加二乙烯基苯的比例，即提高交联度有利于形成单分散的聚合物微球。     

Fe_3O_4／P（St－AA）核－壳复合微球的制备和表征

以磁性氧化铁胶体粒子为种子，运用分散聚合法，制备出具有磁响应性的Ｆｅ_３Ｏ_４／Ｐ（Ｓｔ－ＡＡ）核－壳复合微球。考察了复合微球的形态及结构，测定了复合微球的粒径和磁响应性，研究了分散介质、引发剂、聚合单体和种子粒子等因素对复合微球形成的影响。     

Fe3O4／P（St—AA）核—壳复合微球的制备和表征

以磁性氧化铁胶体粒子为种子，运用分散聚合法，制备出具有磁响应性的Ｆｅ３Ｏ４／Ｐ（Ｓｔ－ＡＡ）核－壳复合微球，考察了复合微球的形态及结构，测定了复合微球的粒径和磁响应性，研究了分散介质，引发剂，聚合单体和种子粒子等因素对复合微球形成的影响。     

单分散双酚A分子印迹微球的制备及其色谱性能

通过改变块状聚合法的合成条件,使用液体石蜡和甲苯的混合溶剂为致孔剂,发展了一种制备双酚A(BPA)分子印迹微球的简单方法。微球的粒径、分散度可通过液体石蜡和甲苯的比例调节。当液体石蜡和甲苯的体积为5mL、体积比为2∶3,EGDMA的量为24mmol时,可得到直径约为3μm、单分散BPA分子印迹微球。液相色谱评价显示,相比于传统的块状聚合方法,本微球具有良好的印迹效应。本法有望成为制备适合于HPLC填充使用单分散分子印迹微球的一种有效方法。     

交联聚膦腈中空微球的可控制备

以分散聚合法制备的聚苯乙烯微球为模板,以六氯环三膦腈、4,4’-二羟基二苯砜为共聚单体,三乙胺为缚酸剂,室温条件下制备出了聚苯乙烯／聚膦腈（核／壳）复合微球,然后用四氢呋喃处理该复合微球,得到聚膦腈中空微球。利用红外光谱、元素分析、扫描电镜及投射电镜对所制备中空微球的结构及形貌进行了表征。结果表明,所制备聚膦腈中空微球...     

聚合物微球调驱剂的制备及其在多孔介质中的微观渗流规律

采用反相微乳液法/乳液法制备了聚合物微球调驱剂，并在微流控芯片中进行了物模实验评价及模拟，分析了聚合物微球调驱剂在岩石孔隙中的输运机理。结果表明：多孔介质的孔隙大于聚合物微球调驱剂直径时，大量微球在微通道中的运移会增加流动阻力及近壁面区域的剪切力；多孔介质的孔隙略大于聚合物微球调驱剂直径时，多个聚合物微球一同进入；在随机生成的多孔介质结构中，微球大颗粒的通过能够导致更大的压力波动，但微球数量越多，滞留情况越严重。     

中空高分子荧光微球的制备及其免疫层析检测应用

以过硫酸钾（KPS）为引发剂,甲基丙烯酸缩水甘油酯（GMA）和苯乙烯（St）为单体,采用无皂乳液聚合法制备了表面官能团化的高分子微球。研究发现添加微量NaCl制备得到的高分子微球,经四氢呋喃（THF）溶胀处理后,能够得到单分散且表面完整的中空P （St-co-GMA）微球。随后使用有机溶胀的方式将Eu(Ⅲ)配合物染料负载于微球壳层中,实现了α1微球蛋白（α1-MG）和β2微球蛋白（β2-MG）的免疫层析检测。     

分散共聚合制备PSt-AA-EGDMA功能性单分散微米级交联微球的研究

以苯乙烯(St)为主单体,丙烯酸(AA)为功能单体,乙二醇二甲基双丙烯酸酯(EGDMA)为交联单体,聚乙烯吡咯烷酮(PVP)为稳定剂,偶氮二异丁腈(AIBN)为引发剂,乙醇/水混合溶剂为分散介质,用分散聚合法一步合成了功能性单分散大粒径(10～20μm)交联聚苯乙烯微球.研究了PSt-AA-EGDMA三元分散共聚合体系的动力学,由转化率-时间关联得到动力学方程;R_p=k[I]^0.13([St]^1.87+[AA]^0.13+[EGDMA]^0.2)·(1+[PVP]^0.2)exp(-E/RT).详细讨论了AA,EGDMA,PVP的浓度和溶剂极性对羧基分布的影响,阐述了AA和EGDMA对粒子形态、粒径及粒径分布的影响.     

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.