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1.
Multifunctional superhydrophobic polymethylsilsesquioxane (PMSQ) surfaces with excellent solvent resistance, thermal stability and enhanced sound absorption property were manufactured by electrospinning. The surfaces with various hierarchical morphologies and hydrophobicity were obtained by electrospinning at the different stages of sol-gel transition of PMSQ prepolymer solution. At the stage with a proper viscosity the superhydrophobic PMSQ surface with a contact angle as high as 151° and a sliding angle as low as 8° was prepared. Due to the excellent thermal stability and solvent resistance properties of the cured PMSQ, the resultant surfaces remain superhydrophobicity after thermal treatment at 300 °C and immersion into many solvents. Additionally, an enhanced acoustical performance and ultra water repellency were obtained simultaneously when the traditional acoustical sponge was decorated with the electrospun PMSQ superhydrophobic surface. The robust superhydrophobic PMSQ surfaces may promise practical applications in many fields.  相似文献   

2.
武德珍 《高分子科学》2013,31(3):427-433
Ladder-like polysilsesquioxanes (LPSQs) with different amino contents have been synthesized by controlling of the dosage of Pd/C catalyst. The concentration and activity of amino groups were investigated by Fourier transform infrared spectroscopy. Polyimide (PI)/LPSQ hybrid films have been prepared by incorporating of the obtained LPSQs with different amino contents into PI matrix, respectively. The interfacial interactions between PI matrix and LPSQ were studied with scanning electron microscopy and X-ray photoelectron spectroscopy, meanwhile the thermal and mechanical properties of the hybrid films were studied using dynamic mechanical analysis and tensile tests. The results indicate that the functionality of LPSQ has great effects on the interfacial interactions and the properties of hybrid films. With the increase of amino content, both the interfacial interactions and the cross-linking density of hybrids enhanced, which results in the decline of surface silicon concentration, increase of Young’s modulus and drop of elongation at break. Excessive amino content makes the hybrid films brittle and leads to incomplete imidization.  相似文献   

3.
A number of cationic gold(I) complexes have been synthesized and found to be stabilized by the use of N-heterocyclic carbene ligands. These species are often employed as in situ-generated reactive intermediates in gold catalyzed organic transformations. An isolated, well-defined species was tested in gold-mediated carbene transfer reactions from ethyl diazoacetate.  相似文献   

4.
The compound bis(acetylacetonato)dichlorotin(IV) [Sn(acac)2Cl2] forms a distorted octahedral structure involving both oxygen atoms of the acetylacetone group. The two chlorides occupy the cis position, with Sn-Cl distances of Sn1-Cl1 = 2.380(2) Å, Sn1-O1 = 2.043(2) Å and Sn1-O2 = 2.093(2) Å. We report here a new and simple method for the synthesis of Sn(acac)2Cl2, its spectroscopic characterization and, for the first time, we report its crystal structure.  相似文献   

5.
Summary Two binuclear AgI complexes, [{Ag(dppp)}2](NO3)2 (1) and [{Ag(dppb)}2(NO3)]2 (2) (dppp = Ph2P(CH2)3PPh2, dppb = Ph2P(CH2)4PPh2], were synthesized and characterized by elemental analysis, t.g., i.r. and 31P-n.m.r. spectra. Single crystals of complex (2) were obtained from MeOH-CHCl3. The X-ray crystal structure shows that the dppb ligand is bidentate, with two ligands bridging two metal ions to form a centrosymmetric dimer.  相似文献   

6.
Yang  Ruina  Lin  Kunhua  Hou  Yimin  Wang  Dongmei  Jin  Douman  Luo  Baosheng  Chen  Liaorong 《Transition Metal Chemistry》1997,22(3):254-258
Binuclear copper(I) complexes [Cu(dppm)(NO3)]2 (1), dppm=Ph2PCH2PPh2, [Cu(dppm)(2,9-Me2Phen)]2(NO3)2 (2), [Cu(dppm)(I)]2 (3) and [Cu(dppm)(py)]2(NO3)2 (4), (py=pyridine) have been synthesized by ligand reduction of cupric nitrate with dppm in EtOH and characterized by elemental analyses, molecular weight determination, t.g.a., 31P-n.m.r spectra; their electronic conductivities and c.v. waves have also been measured. The results show that dppm coordinates as a bridging bidentate ligand to the CuI atoms, and that NO3 behaves as a monodentate ligand or free ion in the newly prepared complexes.  相似文献   

7.
At room temperature, dibenzoyl peroxide undergoes oxidative addition reaction with metallic copper powder and pyridine N-oxide (triphenylphosphine oxide or 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolin) which affords the last products as binuclear copper(II) complexes, [Cu(C5H5NO)-(C6H5COO)2]2(1), [Cu(OPPh3)(C6H5COO)2]2(2) and [Cu(C6H5COO)(C26H2oN2)](3, C26H2oN2 is 2,9-dimethyl-4,7-diphenyl-1,10-phenanthrolin). The structure of the complexes were characterized by elemental analyses, IR spectra, TG-DTA and magnetic property. Crystals(1) are triclinic, space group P1,a=0.92617(36),b=1.06973(17), c=1.08813(29) nm, a=59.60(2)°, β=74.83(3)°,γ=72.80(2)°, V=0.880 nm3, Dc=1.520 g/cm3, Z=1, R=0.044, Rw=0.048, Mr=805.78, 3477 reflections with I > 3σ(I). Each copper(Ⅱ) ion is coordinated by two bridging bidentate benzoate ligands and one pyridine N-oxide or triphenylphosphine oxide to form dimeric binuclear molecules. The structure of the compound(1) shows a clear centre of symmetry.  相似文献   

8.
The 1,1’-dimethylvanadocene dichloride ((C5H4CH3)2VCl2) reacts in aqueous solution with various carboxylic acids giving two different types of complexes. The 1,1’-dimethylvanadocene complexes of monocarboxylic acids (C5H4CH3)2V(OOCR)2 (R=H,CCl3, CF3, C6H5) contain two monodentate carboxylic ligands, whereas oxalic and malonic acids act as chelate compounds of the formula (C5H4CH3)2V(OOC-A-COO) (A=−, CH2). The structure of the (C5H4CH3)2 V(OOCCF3)2 complex was determined by single crystal X-ray diffraction analysis. The isotropic and anisotropic EPR spectra of all the complexes prepared were recorded. The obtained EPR parameter values were found to be in agreement with proposed structures.  相似文献   

9.
[Ru(bipy)2(5-R-phen)](ClO4)2 complexes have been prepared, where bipy=2,2- bipyridine, phen=1,10-phenanthroline, and R=H, Me, NO2 or NH2. The influence of the different 5- substituted phen on the electron delocalization and ligand-ligand interactions have been investigated by solution n.m.r.. The ligand- ligand interaction has also been observed in the solid state by determining the single crystal structure of [Ru(bipy)2(5- NO2-phen)](ClO4)2. The strong steric interaction between the polypyridyl ligands was relieved neither by the elongation of Ru–N bonds (2.055–2.086Å) nor by increase of N–Ru–N bite angles (77.8–79.4°), but rather by distortion of the coordination sphere by forming specific angles (=2.0, 3.2 and 4.2°) between the polypyridyl ligand planes and coordination planes (N–Ru–N), and larger torsion angles (5.8 and 8.2°) between the two pyridine rings for each bipy.  相似文献   

10.
The structure of 1,2-bis(2,4,6-trimethylbenzylideneamino)ethanedichloropalladium(II) was determined by X-ray diffraction methods. The structure derived from NMR and IR spectra and elemental analysis is consistent with it. The complex is orthorhombic, space group Pcab, with a?=?14.8662(12), b?=?15.0861(13), c?=?20.6255(14)?Å, V?=?4625.7(6)?Å3 and Z?=?8. In the lattice, there exists a weak C–H?···?Cl hydrogen bond.  相似文献   

11.
Summary: A simple method for the fabrication of a chemical composition gradient from organic to inorganic by the pyrolysis of a polymethylsilsesquioxane (PMSQ) thin film in a gradient temperature field is reported. The resultant chemical gradient surface demonstrates gradual changes in wettability, and slight microstructural changes are observed along the substrate.

FT‐IR spectra of gradient PMSQ surface along the length from the unheated side to the heated side.  相似文献   


12.
This paper reports the synthesis of a series of methylpyruvate thiosemicarbazone derivatives containing, on the terminal nitrogen, substituents of different nature and size and namely, ethyl, phenyl and methylphenyl. These ligands were reacted with bis(triphenylphosphine)copper(I) nitrate and acetate to produce the respective complexes: [Cu(PPh3)2(Et-Hmpt)]2(NO3)2 (1), [Cu(PPh3)2(Ph-Hmpt)]NO3 (2), [Cu(PPh3)2(MePh-Hmpt)]NO3 (3), [Cu2(O2CCH3)(Et-pt)(PPh3)2] · H2O (4), [Cu(Ph-mpt)(PPh3)] (5) and [Cu2(MePh-mpt)2(PPh3)2] (6). All of them were characterized by elemental analysis, IR, 1H NMR, EPR spectroscopy and, for compounds 1, 2, 4, and 6, by X-ray crystallography. The characterization revealed that the coordinating behaviour of the ligands is influenced by a series of factors, predominant among which is the hard soft nature of the atoms involved in the interactions with the metal centre. The complexes obtained from the nitrate copper(I) salt are formed by cationic molecules with a nitrate as a counterion, while those derived from the acetate salt present deprotonated ligands and a few unexpected features. In particular, one of the compounds (4) is a mixed valence dinuclear complex with an acetate oxygen and the thiosemicarbazone sulfur acting as bridging between the two Cu(I) and Cu(II) ions. Another one (6) presents instead a Cu(I)–Cu(I) sulfur bridged binuclear cluster.  相似文献   

13.
The neutral, mononuclear complex [ReO(mta)2Cl] (1) [Hmta?=?2-(methylmercapto)aniline] was prepared by reaction of trans-[ReOCl3(PPh3)2] with a twofold molar excess of Hmta in methanol. The oxo-bridged dimer (μ-O)[ReO(mta)2]2 (2) was synthesized by reacting [ReOCl3(PPh3)2] with a twofold excess of Hmta in a 9?:?1 acetone/water mixture. The compounds were characterized by spectroscopy and complex 1 also by X-ray crystallography. Complex 1 has a distorted octahedral geometry with the chloride coordinated trans to the oxo group, and with the chelating ligands in the equatorial plane in a cis-N cis-S configuration.  相似文献   

14.
A chiral metal-organic coordination polymer, [Cu(Tar)(2,2′-bipy) · 5H2O] (1) (Tar = L-tartrate dianion, 2,2′-bipy = 2,2′-bipyridine), has been synthesized by hydrothermal reaction of Cu(OAc)2, Na2T (H2T = 2,3-O-isopropylidene-L-tartaric acid) and 2,2′-bipyridine, and characterized by IR, UV–vis spectra, elemental analyses, TG-DTA, and single crystal X-ray diffraction. In the hydrothermal reaction, the protection group isopropylidene for tartaric acid was hydrolyzed. The crystal structure of the coordination polymer 1 shows that each tartrate chelates two Cu(II) ions at opposite ends using one carboxylate oxygen and one hydroxyl oxygen and each Cu(II) ion is chelated by two halves of tartrate dianions, forming coordination polymer chains. Distorted octahedral geometry around copper is completed by a chelating 2,2′-bipyridine molecule. The 2,2′-bipyridine groups in two of parallel 1-D chains are interwoven, constituting ladder-shaped double chains. Strong offset π–π stacking interactions with a face-to-face distance of 3.33 Å for pyridine rings are observed. All the lattice water molecules hydrogen-bond to each other or to the carbonyl oxygen of tartrate, forming a 3-D supramolecular structure.  相似文献   

15.
16.
17.
用三苯基氯化锡与1,5-戊二酸二钠以2:1摩尔比反应,合成了1,5-戊二酸 双(三苯基锡)酯,并进行了红外光谱、核磁共振氢谱及质谱表征。X射线单晶衍 射表明,该化合物属正交晶系,空间群C222(1),晶胞参数:a=1.5075(5)nm, b=4.8021(17)nm,c=2.8944(9)nm,α=90°,β=90°,γ=90°,V=20.953(12) nm^3,Z=8,Dc=1.316g/cm^3,μ=1.226mm^-1,F(000)=8280,R1=0.0546,wR2=0. 1182。晶体结构中存在5种化学环境不同的三角双锥构型的锡原子,由于配体中两 个羧基在不同方向的交联作用,使化合物呈现三维骨架结构,并且在骨架结构中存 在沿a轴和c轴方向伸展的规则的大环直孔道。  相似文献   

18.
在水热条件下合成了一种具有Keggin结构的有机-无机复合的单铈取代夹心型磷钨酸盐[H2dap]2.5H5-[Ce(α-PW11O39)2].11.5H2O(1);利用元素分析、红外光谱和单晶X射线衍射表征了其结构.结果表明,化合物1属于三斜晶系,P-1空间群,晶胞参数为:a=1.254 9(7)nm,b=1.915 9(11)nm,c=2.129 0(12)nm,α=68.426(10)°,β=88.320(10)°,γ=89.853(10)°,V=4.758(5)nm3,Z=2,Dc=4.116g/cm3,GOOF=1.022,R1=0.111 2,wR2=0.218 9.化合物1分子由1个晶体学独立单铈取代夹心型[Ce(α-PW11-O39)2]10-磷钨酸多阴离子,2.5个双质子化的[H2dap]2+阳离子,5个质子及11.5个结晶水分子组成.  相似文献   

19.
以N-甲基苯胺和苯丙炔酸为原料,经过缩合、亲电环化、偶联反应合成了1-甲基-3,4-二苯基喹啉-2(1H)-酮;利用核磁共振谱和气相色谱-质谱表征了产物的结构.结果表明,所用合成方法具有产率高、反应条件温和、操作简单等优点,目标产物的总产率达62.7%.  相似文献   

20.
The novel disulfamethoxazole diaquo Ni(II) monohydrate, [Ni(sulfamethoxazole)2(H2O)2]· H2O, was synthesized, characterized by infrared and electronic spectroscopies and the crystal structure determined. The compound crystallized in the monoclinic centrosymmetric space group P21/c, with four asymmetric units per unit cell. The nickel atoms are in slightly distorted regular octahedra, coordinated by four nitrogen atoms, two from N-arylamine and two from N-sulfonamide with the apical positions occupied by two oxygen atoms from the water molecules.  相似文献   

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