接枝共聚物聚苯乙烯－g－聚氧乙烯的微相分离形态研究

本文利用透射电子显微镜技术，以两性接校共聚物聚苯乙烯－ｇ－聚氧乙烯为研究对象，研究了接枝共聚物的微相分离形态结构，发现聚苯乙烯－ｇ－聚氧乙烯能形成微相分离结构，微区的形状和尺寸与共聚物的组成和侧链长度有关．文中还讨论了嵌段共聚物和接枝共聚物在形成微相分离结构时的共性和个性．     

接枝共聚物聚苯乙烯－g－聚氧乙烯的微相分离形态研究

 本文利用透射电子显微镜技术，以两性接校共聚物聚苯乙烯－ｇ－聚氧乙烯为研究对象，研究了接枝共聚物的微相分离形态结构，发现聚苯乙烯－ｇ－聚氧乙烯能形成微相分离结构，微区的形状和尺寸与共聚物的组成和侧链长度有关．文中还讨论了嵌段共聚物和接枝共聚物在形成微相分离结构时的共性和个性．     

聚烯烃／极性聚合物界面的分子状态

为了克服高分子共混物界面不易表征的缺点，提出用溶剂选择性溶解方法使界面暴露．结合Ｘ－射线光电子能谱（ＸＰＳ）表征手段，研究了官能化聚合物，接枝型共聚物及带有反应性基团的聚合物作为共混物增容剂时在界面区域的分子状态．实验结果表明，作增容剂时，官能化聚合物在界面区内采取最有利的分子构象，充分发挥增容作用；接枝型共聚物主链、侧链向相应本体聚合物内扩散；而带有反应性基团的聚合物与某个本体聚合物发生反应之前存在反应基团在界面富集的过程     

PP－g－PMMA在PP／PVDF共混体系中的应用

利用聚丙烯等离子体接枝甲基丙烯酸甲酯共聚物（ＰＰ－ｇ－ＰＭＭＡ）作增容剂，研究了其在聚丙烯／聚偏氟乙烯（ＰＶＤＦ）共混体系中的作用。增容是通过ＰＭＭＡ与ＰＶＤＦ的偶极－偶极相互作用实现的。接枝共聚物使共混体系的抗张强度和模量均有提高，由不同等离子体处理时间所得的ＰＰ－ｇ－ＰＭＭＡ，接枝率在７．７％～３００％具有最好的增容效果；而由不同后聚合时间所得的共聚物，接枝率在３０％～８０％具有最好的增容效果。     

水溶性聚合物和两亲聚合物：聚（丙烯酰胺－co－丙烯酸钠）－g－聚（β－胺基丙酸）接枝共聚物

合成了端丙烯酰胺基聚（β－胺基两酸）大分子单体，用端基滴定法和１Ｈ—ＮＭＲ法测定了大分子单体的分子量，用１３Ｃ—ＮＭＲ和氢氧化钠水解法测定了支化度．在水溶液中用硫酸亚铁／异丙苯过氧化氢氧化还原引发体系引发丙烯酸胺、丙烯酸钠与聚（β－胺基丙酸）大分子单体的共聚反应，合成了聚（丙烯酰胺－ｃｏ－丙烯酸钠）－ｇ－聚（β－胺基丙酸）接枝共聚物．用１Ｈ—ＮＭＲ和滴定法测定了接枝共聚物的组成．溶液性质的数据表明，与部分水解聚丙烯酰胶相比，聚（β－胺基丙酸）含量较高的接枝共聚物具有较好的耐盐性和优异的贮存稳定性．     

甲壳素和壳聚糖的接枝共聚改性

天然高分子甲壳素、壳聚糖由于分子链上大量存在的反应性官能团 ,易于通过自由基引发与乙烯基单体接枝共聚 ,也可与其它高分子链偶合制得接枝共聚物。通过接枝共聚改性 ,可以赋予甲壳素和壳聚糖以某些新的性能 ,扩大了其应用范围。本文对甲壳素、壳聚糖的接枝共聚改性反应进展、机理以及产物的性能等进行了介绍     

x－甲基丙烯酸2，3－环氧丙基酯与α－甲基丙烯酸甲酯嵌段共聚物的合成与鉴定

α－甲基丙烯酸２，３－环氧丙基酯与■－甲基丙烯酸甲酯嵌段共聚物的合成与鉴定张洪敏侯元雪程■（北京化工大学高分子系北京１０００２９）关键词■－甲基丙烯酸２，３－环氧丙基酯，甲基丙烯酸甲酯，嵌段共聚物■－甲基丙烯酸２，３－环氧丙基酯（ＥＰＭＡ）含有两个可...     

聚酰胺1010／聚乙烯－马来酸酐接枝共聚物共混物力学和热学性能研究

为了表明马来酸酐接枝聚烯烃后对聚酰胺的相容作用，本文研究了聚酰胺１０１０（ＰＡ１０１０）／聚乙烯－马来酸酐接枝共聚物（ＰＥ－ｇ－ＭＡＨ）共混物在不同ＭＡＨ接枝量下的结晶性与力学性能。研究表明，ＭＡＨ的存在导致ＰＥ－ｇ－ＭＡＨ－ｃｏ－ＰＡ１０１０共聚物的形成，而该共聚物在标题共混物中起着相容剂的作用。共混物的结晶性能变化显示了共混组分间存在一定程度的混溶性。在一定的ＭＡＨ含量内，标题共混物具有协同效应。     

乙丙共聚物熔融接枝甲基丙烯酸环氧丙酯

乙丙共聚物熔融接枝甲基丙烯酸环氧丙酯张晓民，尹志辉，殷敬华（中国科学院长春应用化学研究所高分子物理开放实验室长春１３００２２）关键词乙丙共聚物，甲基丙烯酸环氧丙酯，接枝共聚接枝共聚物可作为不相容共混体系的增容剂［１，２］，反应加工法制备乙丙共聚物（Ｅ...     

吸水性淀粉－丙烯腈接枝共聚物的一步合成

以硝酸铈铵为引发剂，在几种水－有机溶剂体系中一步合成了吸水性淀粉－丙烯腈接枝共聚物。其中所含的ＰＡＮ均聚物比水作溶剂时的多。在水－正丁醇溶液（Ｖ／Ｖ＝１∶３）中，ＰＡＮ的接枝效率为８３％，淀粉的接枝效率为７２％，产品的吸水倍数为８２０ｇ／ｇ。     

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.