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将含乙氧基甲基侧链的杯[4]芳烃-1和含硫醚基及正己基侧链的杯[4]芳烃-2作为抗氧剂加入天然橡胶(NR)中,研究其对NR硫化胶物理性能和耐热氧老化性能的影响,并分析其抗氧化机理。结果表明:杯[4]芳烃-1和杯[4]芳烃-2(用量均为1份)对NR硫化胶的物理性能影响均不大,均可有效提高NR硫化胶的耐热氧老化性能;添加杯[4]芳烃-2的NR硫化胶耐热氧老化性能与添加抗氧剂2246S的NR硫化胶相当,优于添加杯[4]芳烃-1的NR硫化胶,这主要归因于杯[4]芳烃-2与NR良好的相容性以及酚羟基与硫醚基的协同抗氧效应。 相似文献
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对叔丁基杯[6]芳烃是杯芳烃的一种基本原料,而杯芳烃由于其环腔大小可调,可进行多种化学修饰等特点,从而有模拟酶催化、传输、分离与富集等方面具有广阔的应用前景,目前大多数杯[6]芳烃的衍生物都是以从对叔丁基杯[6]芳烃出发经适当步骤进行合成的,因而能够以高产率得到对叔丁基杯[6]芳烃具有重要意义。经多年摸索与研究,Gutsche等人将对叔丁基杯芳烃其产率提高到80%以上,但实验方法不易掌握、不易重复,而且和得到的粗产品中往往含有一定量的对叔丁基杯[8]芳烃、对叔丁基杯[4]芳烃等副产品,因而在重结晶纯化以后导致对叔丁基杯[6]芳烃的产… 相似文献
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采用DSC测定氧化诱导期法研究了对叔丁基杯[n]芳烃(n=4、6、8)对聚丙烯(PP)热稳定性的影响,并研究了对叔丁基杯芳烃对聚丙烯(PP)力学性能和结晶性能的影响.结果表明,一定量对叔丁基杯芳烃可以显著提高PP的热氧稳定性,并且还能起到异相成核作用从而增加PP的结晶度和冲击强度. 相似文献
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对叔丁基苯酚和甲醛在KOH催化下制备对叔丁基杯[6]芳烃。用荧光光谱法研究了对叔丁基杯[6]芳烃与黑索金(RDX)在溶液中的相互作用,结果表明对叔丁基杯[6]芳烃与RDX在溶液中存在较强的配合作用,RDX的激发峰发生明显红移,荧光强度增强,主客体间发生了包合作用。通过对叔丁基杯[6]芳烃-RDX配合物的发射光谱与紫外光谱分析,确定了在DMF溶液中对叔丁基杯[6]-RDX配合物的化学计量比为1∶1,稳定常数为325.70。 相似文献
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对叔丁基杯[4]芳烃与对甲苯磺酸酯基乙氧基对苯甲醛反应生成对叔丁基杯[4]芳烃-1,3-二醛基衍生物1,对叔丁基杯[4]芳烃-1,3-二醛基衍生物1与金刚烷胺进行分子间缩合反应得到含金刚烷基的新型杯[4]芳烃衍生物,并利用1H NMR,13C NMR,MS和元素分析对目标化合物的结构进行了表征。初步的抗菌试验表明,该化合物表现出较好的抑菌活性。 相似文献
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Tatsuya Oshima Ryota Saisho Kaoru Ohe Yoshinari Baba Keisuke Ohto 《Reactive and Functional Polymers》2009,69(2):105-110
Macrocyclic host molecules calixarene carboxylic acid derivatives are found to act as powerful extractants for biologically important amino compounds. A series of adsorbents were prepared from a methacrylate-based polymer Amberlite XAD-7 by impregnation with various calixarene derivatives, for adsorptive recovery of amino acid derivatives. The larger macrocycles calix[6]arene and calix[8]arene carboxylic acid derivatives were more effective for adsorption of amino acid derivatives on the impregnated resin than the calix[4]arene derivative. Since adsorption proceeds mainly via electrostatic interaction, the carboxylic acid groups introduced into the calixarene platform were important for adsorption of cationic amino acid derivatives. The adsorption selectivity for amino compounds using adsorbent impregnated with the calix[6]arene carboxylic acid derivative depends simply on the hydrophobicity of the adsorbates. 相似文献
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Bernd Garska Monir Tabatabai Urs Fischer Norbert Moszner Andreas Utterodt Helmut Ritter 《Polymer International》2012,61(7):1061-1066
We describe the synthesis of 5,11,17,23‐tetra‐tert‐butyl‐25,27‐dioxypropylphosphonic acid‐26,28‐dimethacryloyloxy‐calix [4]arene and 5,11,17,23‐tetra‐tert‐butyl‐25‐oxypropylphosphonic acid‐27‐hydroxy‐26,28‐dimethacryloyloxy‐calix[4]arene starting from para‐tert‐butyl‐calix[4]arene. The complete reaction was proved by matrix‐assisted laser desorption ionization time of flight mass spectrometry and nuclear magnetic resonance spectroscopy. The influence of these compounds on the kinetics of the radical polymerization of methyl methacrylate was shown by dilatometry. Furthermore, the adhesive properties of dental adhesives containing these calix[4]arene derivatives were investigated. Copyright © 2012 Society of Chemical Industry 相似文献
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杯芳烃作为超分子化学的重要组成部分,近年来得到了快速发展并成为化学家的研究热点。以脱叔丁基-杯[4]芳烃为原料合成了杯[4]芳烃偶氮衍生物,其结构经IR和1H NMR所表征。研究了该主体分子对金属离子的萃取性能,实验结果表明,该主体分子对Mg2+具有较高的萃取作用。讨论了主客体间配位作用的机制。 相似文献
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P. Amruta Reddy Ram P. Kashyap William H. Watson C. David Gutsche 《Israel journal of chemistry》1992,32(1):89-96
Chlorine dioxide and thallium trifluoroacetate are shown to be useful reagents for the preparation of calixquinones. p-H-Calix[4]arene( 1a ),p-H-calix[5]arene ( 1b ), and p-H-calix[6]arene ( 1c ) are oxidized in modest yields by ClO2 to the fully quinonoid compounds calix[4]tetraquinone ( 2a ), calix[5]pentaquinone ( 2b ), and calix[6]hexaquinone ( 2c ), respectively. Although Tl(OCOF3)3 is less effective for the oxidation of 1a-c , it proves to be the reagent of choice for converting partially etherified or esterified calixarenes carrying p-tert-butyl groups directly to partially quinonoid calixarenes. Thus, monosubstituted calix[4]arenes yield triquinones; disubstituted calix[4]arenes yield diquinones; trisubstituted calix[4]arenes yield monquinones; and tetrasubstituted calix[6]arenes yield diquinones. The structures of the calixquinones have been established by elemental analysis, 1H NMR spectroscopy, mass spectroscopy, and in the case of 2c by X-ray crystallography. Since the starting materials are readily accessible, the calixquinones become easily available compounds for further study. 相似文献
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Polyaniline (PANI) molecular composites were synthesized by chemical oxidative polymerization of the aniline and aniline dimer, N‐phenyl‐1,4‐phenylendiamine, in the presence of a macrocycle, calix[8]arene p‐octasulfonic acid (C8S), using ammonium peroxidisulfate as oxidant. The macrocycle has acted both as acid dopant and surfactant to obtain processable PANI‐ES. The PANI/calix[8]arene p‐octasulfonic acid composite was also obtained by a simple doping of PANI emeraldine base form with calix[8]arene sulfonic acid. The structure of materials was confirmed by Fourier transform infrared, UV–vis and nuclear magnetic resonance spectroscopy. All synthesized composite materials are amorphous and soluble in chloroform, dimethylsulfoxide, NMP, showing excellent solution‐processing properties combined with electrical conductivity. Cyclic voltammetry evidenced a good electroactivity for the composite films. Dielectric properties (dielectric constant and dielectric losses) were determined and are comparable with those of other PANI/ionic acid polymer composites. Preliminary studies have evidenced a high dielectric constant (104 at 100 Hz) and electrical conductivity of 6 × 10?3 S/cm for PANI composites. From sulfur elemental analysis of the PANI/calixarene, it results that the content in macrocycle is ~30% (weight). © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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以对叔丁基苯酚、甲醛为主要原料合成杯芳烃母体对叔丁基杯[n]芳烃(n=4,6,8);以1,3-丙烷磺内酯、1,4-丁烷磺内酯为醚化试剂,经Williamson醚化反应,合成出6种杯芳烃基低聚表面活性剂。利用IR表征了中间体和最终产物的结构,确定了化合物的结构与所设计的分子结构相同。用染料法对所合成产物进行了定性鉴定,并用滴体积法测定了表面活性剂水溶液25℃时的表面张力。结果表明,随着杯芳烃空腔的逐渐增大,cmc值降低,γcmc值升高,Γcmc值下降,Am值升高。 相似文献
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Copolyethers and polyurethanes containing lower and upper rim calix[4]arene units in the fixed cone conformation were prepared in good yield by polycondensation reactions of distal calix[4]arene diols with bisphenol-A/dibromomethane and 2,4-tolylendiisocyanate (TDI), respectively. In a similar way were prepared calix[4]arene-crown-5 and -crown-6 polyurethanes in the fixed 1,3-alternate conformation by condensation of TDI with lower rim calixcrown-5 and calixcrown-6 diols. However, the poor solubility in common organic solvents of the copolyether derivatives (Mw=11,100-11,600 g/mol) hampered further studies on their ionophoric properties. Aiming to obtain model compounds for the investigation of both extraction abilities and ionophoric properties of the polyurethane materials, several bis-urethanes were also synthesized by reaction of the calix[4]arene diols with p-tolylisocyanate (TI). The extraction ability measurements of monomeric and polymeric calix[4]arene urethanes (Mw=12,300-83,500 g/mol) towards alkali metal cations (Li+, Na+, K+, Rb+, Cs+) and Ag+showed a remarkable efficiency and selectivity of calixcrown-6 polyurethane toward Rb+, Cs+and Ag+. 相似文献
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N. M'hanni T. Anik R. Touir M. Galai M. Ebn Touhami E.H. Rifi Z. Asfari S. Bakkali 《中国化学工程学报》2022,44(4):341-350
Nichel-phosphorus (Ni-P) coatings are deposited on mild steel by using an electroless plating process. The effect of three calix[4]arene derivatives, namely tetra methyl ester-P-tertbutyl calix[4]arene (Calix1), tetra acid-P-tert-butyl calix[4]arene (Calix2) and tetra methyl P-tert-butyl-thicalix[4]arene ester (Calix3) on the deposition rate, the deposit composition, and the morphological surface was investigated and the study of growth mechanisms has delivered useful information about the surface properties of deposit. It is found that these additives modify the deposition rate and the nickel crystallization process. In fact, the Calix1 and Calix3 act as an accelerator, while Calix2 acts as an inhibitor for the nickel electroless. Furthermore, it is shown that the chemical bath is more stable with calix[4]arene derivatives addition and the obtained deposits are compact and adherent. It is observed also that the nickel content increases with additives. On the other hand, the X-ray diffraction showed that the orientation peaks are intensified at {1 1 1} in the presence of Calix2, confirming obtained results of EDAX spectrum. The cyclic voltammetry revealed that the tested additives strongly influence the cathodic process and slightly affect the hypophosphite oxidation. Finally, it is found that these compounds improve the anticorrosion efficiency of Ni-P coating on the mild steel substrate in 3% (mass) NaCl, where its polarization resistance increases with Calix2 and Calix3 addition. 相似文献
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A styrene based water soluble polymer containing pendant sulfonated calix[4]arene groups has been synthesized by using free radical polymerization combined with post-polymerization sulfonation chemistry. The monomer 25-(4-vinylbenzyl)-26, 27, 28-hydroxy-calix[4]arene (VBC4A) was prepared in 3 steps: (1) reduction of 4-vinyl benzoic acid to the respective alcohol (2) formation of the bromide by the Appel reaction and (3) synthesis of the respective ether by Williamson O-alkylation reaction with calix[4]arene. Polymerization was accomplished by azobisisobutyronitrile (AIBN) initiated free radical polymerization technique to afford P(VBC4A) with Mn value of 7090 g/mol and moderate polydispersity. The resulting P(VBC4A) was subsequently reacted with acetyl sulfate to afforded the sulfonated polymer. The reaction was followed by nuclear magnetic resonance and infrared spectroscopy, and the results suggest that the sulfonation reaction lead to nearly quantitative functionalization of the calixarene functional polymer. Elemental analysis by X-ray photoelectron spectroscopy confirmed these findings on the degree of sulfonated functionalization. Electro-responsive properties of the sulfonated polymer were studied by cyclic voltammetry and isothermal titration calorimetry in phosphate buffer saline solution. A response to electrochemical stimulus is observed where guest molecules of methyl viologen incorporate and dissociate with P(VBSC4A). 相似文献