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1.
A novel POSS-containing organic-inorganic hybrid crosslinked polymer was prepared by hydrosilylation reaction of octahydridosilsesquioxane (T8H8) with 4,4'-bis(4-allyloxybenzoyloxy)phenyl (diene A). Its structure and property was character-ized by FTIR, 29Si NMR, TGA and ellipsometer, respectively. The results show that the hybrid polymer possesses high thermal stability and low dielectric constant of 1.97 at optical frequencies.  相似文献   

2.
<正>A novel polyhedral oligomeric silsesquioxane(POSS)-based organic-inorganic hybrid nanocomposite(EF-POSS) was prepared by Pt-catalyzed hydrosilylation reaction of octahydridosilsesquioxane(T_8H_8,POSS) with a luminescent substituted acetylene(2- ethynyl-7-(4-(4-methylstyryl)styryl)-9,9-dioctyl-9H-fluorene(EF)) in high yield.The hybrid nanocomposite was soluble in common solvents such as CH_2Cl_2,CHCl_3,THF and 1,4-dioxane.Its structure and property were characterized by FTIR, NMR,TGA,UV and PL,respectively.The results show that the hybrid nanocomposite with high thermal stability emits stable blue light as a result of photo excitation and possesses high photoluminescence quantum efficiency(φ_(FL)).  相似文献   

3.
Cross-linked polyethylene (XLPE) films have been coated with nanostructured hybrid organic-inorganic coatings in order to improve their durability. For this purpose, bi- and mono-layer coatings containing different amount of silica and different organic polymers have been prepared through sol-gel reactions and applied to XLPE commercial films. The thermo-oxidative stability, electrical strength and conductivity of XLPE coated films have been investigated after ageing in air at temperatures above the on-service conditions, i.e. at 105 and 120 °C for 1900 and 600 h, respectively. The performed investigations (FT-IR, DSC, TGA and electrical properties) showed that all the coatings tested were able to strongly protect XLPE against oxidation, and that the coating with a PVOH/SiO2 layer gave the best protection. The increase of thermal resistance induced by the coatings reflects on the electrical strength after ageing, which is higher for coated samples than for uncoated ones. Moreover, while ageing has only a slight effect on electrical conductivity in different coated samples, a strong increase of conductivity was observed after ageing for highly oxidated uncoated samples.  相似文献   

4.
Organic-inorganic hybrid coatings containing quaternary ammonium salts (QAS) bonded to the organic-inorganic network were prepared from tetraethoxysilane and triethoxysilane terminated poly(ethylene glycol)-block-poly(ethylene) using a sol-gel process. They were applied as a thin layer (0.6-1 μm) to PE films and the antibacterial activity of the coated films was tested against both Gram-negative (Escherichia coli ATCC 25922) and Gram-positive (Staphylococcus aureus ATCC 6538) bacteria. Measurements at different contact times showed a rapid decrease of the viable count for both the tested strains. In particular, after 48 h of contact, a decrease of 96.4% and 99.1% of E. coli and S. aureus, respectively, was observed. The permanence of the antibacterial activity of the coated films was demonstrated through repeated washings and prolonged immersion in physiological saline solutions at 37 °C. Indeed, due to the removal of QAS moieties by the nucleophilic attack of water, the antibacterial activity after 24 h was strongly reduced when measured on samples submitted to several washings. However, a quite good antibacterial activity was observed even on the same samples after 96 h, probably due to a spontaneous partial restoring of the QAS on the surface. Very good transparency, quite good adhesion and high wettability are further features of these hybrid coatings.  相似文献   

5.
The reactivity of the [Mo7O24]6− anion towards the structure directing-reagent piperazine (pipz) has been investigated and new synthetic routes to achieve the known (H2pipz)3[Mo8O27] 1, (H2pipz)[Mo3O10]·H2O 2, and (H2pipz)[Mo5O16] 3 molybdenum(VI) containing compounds are proposed. The role of the pH on the stabilization of the different compounds and their interconversion pathways is discussed. Compounds 1 and 2 show photochromic behavior under UV excitation, related to the particular organization of the organic component around the mineral framework. Their optical properties are reported and commented.  相似文献   

6.
The immobilization of copper in organic-inorganic hybrid materials catalyzing the Ullmann reaction has been described. Phenols reacted with aryl iodides, aryl bromides and aryl chlorides smoothly in the presence of a 3-(2-aminoethylamino)propyl functionalized silica gel immobilized copper catalyst. The protocol involved the use of DMSO as the solvent, and potassium fluoride as the base. The reactions generated the corresponding cross-coupling products in good to excellent yields. Furthermore, the silica-supported copper could be recovered and recycled by a simple filtration of the reaction solution and used for 10 consecutive trials without loss of its reactivity.  相似文献   

7.
Organic-inorganic hybrid coatings, obtained through the sol-gel chemistry from tetraethoxysilane and polyethylene-poly(ethylene glycol) block copolymer, have been prepared in different compositions and applied to untreated and plasma treated LDPE films by spin coating. The mechanical properties of the coatings and the adhesion between coating and substrate have been characterized by fragmentation test. An increase in coating strength, elongation at break and adhesion has been observed with increasing the organic fraction in the hybrid coating. A plasma treatment of the LDPE surface, just before the application of the coating, lead to an increase of the adhesion between coating and substrate (interfacial shear strength), leaving almost unaffected coating strength and strain at fragmentation onset.  相似文献   

8.
The oxygen barrier properties of composite materials, consisting of a 45 μm thick LDPE substrate coated by a thin layer (0.7-1 μm) of new hybrid organic-inorganic materials based on SiO2 and PE-PEG block copolymers, have been characterized at 35 and 50 °C. A significant decrease (25-40%) of the oxygen transfer rate has been observed for coated samples with respect to bare substrate both at 35 and 50 °C. The effects on the coating permeability of organic-inorganic ratio, molecular weight of the PE-PEG block copolymers and temperature are discussed.  相似文献   

9.
In this work, a new orthorhombic organic-inorganic hybrid single crystal (C2H10N2)2MnBr4.2Br with-Zero-dimensional structure was synthesized by slow evaporation method at 75 °C. The crystal structure and intermolecular interactions were performed by single crystal X-ray diffraction and Hirshfeld surface. Optical properties of (C2H10N2)2MnBr4.2Br were systematically studied by Raman, infrared spectrum, UV–vis, photoexcitation spectra, and photoluminescence spectra. The optical band gap (Eg = 2.61 eV) were calculated from the absorption spectra of (C2H10N2)2MnBr4.2Br. This hybrid materials also had shown good thermal stability (decomposition temperature: 288–660 °C). Finally, photoluminescence measurements showed a strong excitation line at 362 nm and a strong fluorescence at 537 nm which makes it a promising material in luminescence field.  相似文献   

10.
The solid hybrid material (H3/4pbpy)4[PMo12O40]·1.25H2O (1) (pbpy=5-phenyl-2-(4-pyridinyl)pyridine) has been prepared and characterized. A structural feature of compound 1 is that the polyoxometalate anions exhibit a one-dimensional inorganic double chain-like structure via weak interactions of O…O. The organic moiety exhibits regular packing with offset aromatic-aromatic interactions between the pbpys, leading to a compact supramolecular framework structure to accommodate the inorganic chains. Compound 1 was employed to fabricate the three-dimensional bulk-modified carbon paste electrode (1-CPE) to research on its electrochemistry properties. The results indicate that 1 retained Keggin molybdate anion electrocatalytic activities toward the reduction of chlorate, hydrogen peroxide and nitrite.  相似文献   

11.
UV‐curable fluorinated organic–inorganic hybrid coatings were prepared by the sol–gel technique. Perfluorinated urethane modified alkoxysilane was synthesized by the reaction between perfluoro alcohol and 3‐isocyanatopropyltrimethoxysilane. The prepared formulations were applied onto poly(methyl methacrylate) (PMMA) and acrylonitrile butadiene styrene (ABS) panels and polymerized by UV‐curing. The properties of the hybrid coatings such as hardness, chemical resistance, thermal stability, surface morphology, double bond conversion, and also contact angle measurements were investigated. Contact angle measurements have shown that the addition of fluorinated silane precursor to the hybrid system improved the water repellency and increased the contact angle from 65° to 106°. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

12.
We designed and synthesized an organic-inorganic hybrid compound (TPE8-OV), which is comprised of an octavinylsilsesquioxane-core and TPE-peripheries. This compound exhibits good thermal stability and typical Aggregation-Induced Emission (AIE) characteristics. Interestingly, it shows good sensitivity to picric acid (PA), and the largest quenching constants of TPE8-OV is up to 174,140 M?1. Furthermore, efficient non-doped OLEDs based on it afford remarkable performance.  相似文献   

13.
A novel one-dimensional (1D) coordination polymer [{Cu(2,2′-bpy)}6(Mo6O22)][GeMo12O40]·H2O (2,2′-bpy=2,2′-bipyridine), which represents the first example of 1D organic-inorganic hybrid based on a Keggin-type heteropolyanion [GeMo12O40]4− and an unprecedented isopolyanion [Mo6O22]8−, has been hydrothermally synthesized and characterized by single crystal X-ray diffraction. Crystal data: C60H50Cu6GeMo18N12O63, monoclinic, P21/c, a=13.9344(3), b=20.0329(3), c=17.2151(3) Å; β=94.0220(10)°, V=4793.70(15) Å3, T=293(2) K; Z=2.  相似文献   

14.
The photooxidative behaviour of a new kind of hybrid system based on silanised poly(ether-urethane)s (SPURs) has been analyzed by Fourier transform infrared spectroscopy (FTIR) and atomic force microscopy (AFM). The influence of polyether molecular weight and SPUR chemical nature as well as the addition of HALS and UVA stabilizers on the system photodegradation has been studied.FTIR results and AFM images have shown that the light stabilizers considerably enhance the photodegradation resistance, specially the HALS type stabilizer.  相似文献   

15.
近十年来,随着纳米科技的发展,有机.无机杂化一维纳米材料的设计合成与应用成为了自然科学领域的研究热点.本文综述了由有机小分子与无机组分杂化而成的一维纳米材料的合成方法,包括水热/溶剂热法、共沉淀法、非水相溶胶凝胶法、模板法、后嵌入法等.并对有机一无机杂化一维纳米材料的二次转化,如通过二次转化获得功能性一维氧化物、碳氮化物、硫属化合物及高分子杂化纳米材料,进行了讨论与展望.  相似文献   

16.
陈玉洁  谢明雪  冯卓  邓启良 《色谱》2017,35(12):1240-1244
以烯丙基三乙氧基硅烷与1-乙烯基-3-辛基咪唑溴盐离子液体为单体通过自由基聚合及溶胶-凝胶制备了有机-无机杂化聚离子液体材料。通过红外光谱和扫描电镜对所制备的杂化聚离子液体材料进行了表征,并考察了其对柠檬黄、日落黄、苋菜红以及诱惑红等常见染料的吸附性能。研究结果表明:所制备的聚离子液体材料对日落黄和诱惑红具有优异的吸附性能,其吸附容量分别为29.20和86.17 mg/g;当吸附时间为5 min时,该材料对诱惑红和日落黄的吸附分别达到平衡时吸附量的87.5%和72.8%,显示了较快的吸附速率。  相似文献   

17.
Different types of silanized polyurethanes (SPUR) were prepared in two ways: the first type (a), by reacting a polyether diol with an isocyanatesilane and the second type (b) by reacting it with diisocyanate (IPDI) and afterwards with aminosilane. These systems are able to cure with atmospheric moisture and, as a consequence, a tridimensional hybrid structure is formed where the inorganic and organic phases are bonded with covalent bonds. The evolution of the curing process in both systems has been monitored by means of Fourier transform infrared spectroscopy, through the changes observed in the carbonyl stretching vibration region. The results obtained show that the SPURs of kind (b) present stronger hydrogen bonding interactions as a consequence of urea groups present in the final structure. Moreover, given the proximity of both urethane and urea groups to alkoxysilane end groups, during the alkoxysilane curing process these groups are forced to approximate themselves even further and therefore the reticulation process leads to an increase of the self association of urethane and urea groups.Finally, DSC has been used to measure Tg values of the systems studied before and after the curing process. The obtained results have confirmed the main conclusions obtained in FTIR analysis.  相似文献   

18.
杨帆  毛劼  何锡文  陈朗星  张玉奎 《色谱》2013,31(6):531-536
发展了以巯基-烯点击反应制备有机-无机杂化硼酸亲和整体柱的新方法。首先以四甲氧基硅烷(TMOS)和巯丙基三甲氧基硅烷(MPTMS)作为反应单体,采用溶胶-凝胶反应制备表面含巯基的硅胶整体柱。然后利用巯基-烯(thiol-ene)的点击反应在整体柱上修饰硼酸配基3-丙烯酰胺基苯硼酸(AAPBA),制成AAPBA-硅胶杂化亲和整体柱。对影响硼酸亲和整体柱性能的条件如TMOS与MPTMS的比例、聚乙二醇和甲醇的用量等进行了优化。并采用扫描电镜、红外光谱等分析仪器对整体柱形貌和机械稳定性能进行了表征。研究了AAPBA-硅胶杂化亲和整体柱的分离性能,结果表明,其在中性条件下对含有顺式二醇的生物小分子核苷具有良好的特异亲和能力,并已成功地应用于卵清蛋白、辣根过氧化物酶等糖蛋白的分离。基于巯基-烯反应的制备方法新颖、可靠,可用于制备多种不同类型的硼酸亲和整体柱,具有较大的应用前景。  相似文献   

19.
An organic-inorganic hybrid poly-o-toluidine Th(IV) phosphate was chemically synthesized by mixing ortho-tolidine into the gel of Th(IV) phosphate in different mixing volume ratios, concentration of inorganic reactant with a fixed mixing volume ratios of organic polymer. The physico-chemical characterization was carried out by elemental analysis, TEM, SEM, XRD, FTIR and simultaneous TGA-DTA studies. The ion-exchange capacity, chemical stability, effect of eluant concentration, elution behavior and pH titration studies were also carried out to understand the ion-exchange capabilities. The distribution studies revealed that the cation-exchange material is highly selective for Hg2+, which is an important environmental pollutant. Due to selective nature of the cation-exchanger ion-selective membrane electrode was fabricated for the determination of Hg(II) ions in solutions. The analytical utility of this electrode was established by employing it as an indicator electrode in electrometric titrations.  相似文献   

20.
Pinhua Li 《Tetrahedron》2007,63(25):5455-5459
Recycling copper(I) immobilized on organic-inorganic hybrid material behaves as a very efficient heterogeneous catalyst in the three-component Mannich coupling reaction of aldehydes, terminal alkynes, and amines via C-H activation to afford the corresponding products in good to excellent yields under solvent-free reaction conditions.  相似文献   

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