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1.
A series of room-temperature ternary deep eutectic solvents(TDESs) were prepared from imidazolium halides, zinc halides and amides. The [BMIM]Cl–ZnCl2 –acetamide(1:1:1) system shows the lowest freezing point( 60 8C) and lowest density in the series. The viscosity and conductivity of TDESs have an exponential relationship with temperature and can be fitted by Arrhenius equation.  相似文献   

2.
Pyriminostrobin, a new acaricide, was discovered in our previous studies. Because introducing fluorine into organic compounds can increase bioactivity, pyriminostrobin was modified as a series of strobilurin-pyrimidine derivatives for biological screening. The compounds were characterized by 1H NMR, MS and elemental analysis. Preliminary bioassays demonstrated that compounds 7e and 7i exhibited significant control against Tetranychus cinnabarinus (Boisd.) at 0.625 mg L^-1, and their acaricidal potencies were higher than pyriminostrobin in a greenhouse. The relationship between structure and acaricidal activity was also studied.  相似文献   

3.
Novel functional hyperbranched poly(aryl ether ketone)s(HPAEKs) bonded with nonlinear optical chromophores(meso-tetrakis(4-hydroxyphenyl) porphyrin, THPP and its metal derivatives) were synthesized and characterized by 1H-NMR and UV-Vis absorption spectra. The incorporation of chromophores into HPAEKs endowed HPAEKs novel NLO and OL properties. Indeed, dendritic architecture allowed for maximum dispersion of the chromophores, avoided aggregation, more optical limiting property was obtained. Simultaneously, they retained the excellent properties of the materials, particularly in thermal stability. Their optical properties were evaluated by nonlinear optical analyses and optical limiting. The results showed that these polymers possessed good optical limiting(OL) property and large nonlinear optical(NLO) susceptibilities(ca. 10 12esu). All polymers containing chromophores presented excellent thermal stability(DT5 524.17 °C).  相似文献   

4.
(E)-Methyl-2-(2-(bromomethyl)phenyl)-3-methoxyacrylate was reacted with substituted 1-acetylpyr-rolidine-2,4-diones and 3-(1-(hydroxylamino)ethylidene)pyrrolidine-2,4-diones respectively to synthesize two series of/%methoxyacrylate derivatives containing the pyrrolidine-2,4-dione moiety. The structures of the targeted compounds were confirmed by IR, 1H NMR, 13C NMR, MS and elemental analysis. The fungicidal activity against Rhizoctonia solani, Botrytis cinerea and Fusarium graminearum was evaluated. The bioassay results demonstrated that these compounds showed visible fungicidal activity.  相似文献   

5.
唐涛 《高分子科学》2014,32(1):51-63
A variety of linear and 3-arm star polyethylene (PE) model polymers covering a wide range of molecular weight are synthesized by the living polymerization of butadiene and the subsequent hydrogenation. Several rheological parameters of these model linear and 3-arm star PE samples are analyzed for detecting the long chain branching (LCB) structure. It is found that the analyses based on zero shear viscosity, vGP plot and flow activation energy are very sensitive to the 3-arm star PEs. The information on the presence of LCB can be obtained with these methods even for low molecular weight samples, which can not be determined by GPC-MALLS. However the information about the LCB structure can not be obtained by the rheological methods alone.  相似文献   

6.
赵京波 《高分子科学》2014,32(2):187-196
Two polyborosiloxanes(PBSis) with char yield up to 74.13% at 800 °C were synthesized by the direct polycondensation of boric acid with phenyltrimethoxysilane in diglyme. The PBSis were characterized by gel permeation chromatography, IR spectroscopy as well as1H-,29Si- and11B-NMR. PBSi modified phenol-formaldehyde resins(PBSi/PFs) were prepared at different PBSi/PF mass ratios and were cured at 150 °C. The PBSi/PFs were characterized by IR spectroscopy, scanning electron microscopy, thermogravimetric analysis and tensile test. The results revealed that the cured PBSi/PFs had sea-island morphology and higher char yield than the common PF. PBSi/PF blend with PBSi/PF mass ratio of 0.4:1 had char yield up to 70.83% at 800 °C. The PBSi/PFs had tensile strength similar to PF. The ceramization of PBSi/PFs was also studied. The silicon boron oxycarbide(SiBOC) ceramics formed were characterized by IR spectroscopy and elemental analysis. This method provided a valuable way to prepare easily shapeable polymer blends as ceramic precursors.  相似文献   

7.
朱长进 《高分子科学》2014,32(2):151-162
A novel series of polyphosphazene-grafl-polystyrene (PP-g-PS) copolymers were successfully prepared by atom transfer radical polymerization (ATRP) of styrene monomers and brominated poly(bis(4-methylphenoxy)phosphazene) macroinitiator. The graft density and the graft length could be regulated by changing the bromination degree of the macroinitiator and the ATRP reaction time, respectively. The PP-g-PS copolymers readily underwent a regioselective sulfonation reaction, which occurred preferentially at the polystyrene sites, producing the sulfonated PP-g-PS copolymers with a range of ion exchange capacities. The resulting sulfonated PP-g-PS membranes prepared by solution casting showed high water uptake, low water swelling and considerable proton conductivity. They also exhibited good oxidative stability and high resistance to methanol crossover. Morphological studies of the membranes by transmission electron microscopy showed clear nanophase-separated structures resulted from hydrophobic polyphosphazene backbone and hydrophilic polystyrene sulfonic acid segments, indicating the formation of proton transferring tunnels. Therefore, these sulfonated copolymers may be candidate materials for proton exchange membranes in direct methanol fuel cell (DMFC) applications.  相似文献   

8.
Nanocomposites of polyaniline(PANI) and the macrocycle thiacalix[4]arene tetra sulfonate(TCAS) were successfully synthesized in feed ratios of 1:0.25, 1:0.50 and 1:0.75 by three prevail synthetic methods, i.e. in situ polymerization, emulsion polymerization and solution casting technique. The structures of the nanocomposites were confirmed by FTIR, UV-Vis, XRD, SEM, and TEM techniques. The conductivity was measured by a four probe method. The conductivity was recorded to be as high as 105 × 10 2S cm 1for the nanocomposite with a nanometer size structure and homogeneously distributed morphology. The electroactivity of the nanocomposites was approved by cyclic voltammetry(CV) and impedance spectroscopy technique(EIS). The antioxidant ability and thermal property of the composites were further studied. Preliminary studies have evidenced the production of conductive nanocomposites with good thermal property and relatively good solubility in N-methyl 2-pyrrolidone(NMP), with the antioxidant activity reaching up to 80%.  相似文献   

9.
An efficient and facile synthesis of a library of hitherto novel 1,2,3-triazolyl-N-acetyl/N-propionylpyrazoline hybrids(16 examples) in excellent yields(90%–96%) has been accomplished from easily accessible 1,2,3-triazolyl chalcone precursors.  相似文献   

10.
余龙 《高分子科学》2014,32(1):108-114
Morphology and phase compositions of different starch-gelatin blends were investigated by various microscopes: optical, SEM and synchrotron FTIR microscopy. A high amylose(80%) corn starch, grafted with hydroxypropyl to enhance flexibilty and hydrophilicity, and plasticized by poly(ethylene glycol)(PEG), was used in this work. SEM revealed that the surface became smoother after adding PEG. Optical microscopy observation revealed that compatibility between gelatin and starch was improved by adding PEG. An FTIR beam focused on a 5 μm× 5 μm detection area by the micro-spectroscope was used to map chemical composition. The ratio of areas of the saccharide bands(1180–953 cm 1) and the amide I and II bands(1750–1483 cm 1) was used to monitor the relative distributions of the two components in the blends. The FTIR maps indicated that gelatin constituted the continuous phase up to 80% of starch content. All of the FTIR spectra showed contributions from both starch and gelatin absorptions, therefore indicating that complete demixing with pure starch and gelatin domains did not occur. The PEG improved the compatibility of the gelatin-starch blends.  相似文献   

11.
The beta-cyclodextrin (beta-CD) inclusion complex containing di(8-hydroxyquinoline)magnesium was prepared. The product was characterized by NMR, IR, differential thermal thermogravimetric analysis (DT-TGA), spectrofluorimetry, and elemental analysis, indicating the formation of inclusion complex in which the quinoline rings of the guest were encapsulated within the beta-CD cavities. The Job's method provided 2:1 stoichiometry for the inclusion complex between beta-CD and di(8-hydroxyquinoline)magnesium. The association constant calculated with the modified Benesi-Hildebrand equation at 25 degrees C was determined. And the mean association constant was 3577 (L/mol)2, R.S.D. was 2.58%. The thermal stability and solubility of di(8-hydroxyquinoline)magnesium were improved when forming inclusion complex.  相似文献   

12.
含磷、硫、氮配原子的钴羰基簇合衍生物的合成和表征   总被引:1,自引:0,他引:1  
过渡金属原子簇化学是当今化学学科中非常活跃的研究领域之一 ,这类簇合物大多有着新颖的几何构型和多样化的成键方式 ,并且具有独特的催化性能[1 ] 。迄今为止 ,人们合成了多种含磷、硫、氮等原子的铁、钴、钌等羰基簇合衍生物 ,但其中三种以上原子同时配位的情况并不多见 ,有金振兴等的含C、S、N配原子的三核钴簇[2 ] ;Luga和Cabeza的三钌簇[3 ,4] 以及Chihara等合成的五核钌簇[5] ,其分子中都有P、N、O三原子配位。我们利用复杂的含P、S、N等可配原子的有机配前体与二元钴羰合物反应 ,合成了一系列三核、四核…  相似文献   

13.
Two series of novel push–pull 1-(4-(thiophen-2-yl)phenyl)-1H-pyrroles 35 were designed to explore the consequence of using different electron accepting moieties linked to the thiophene at the arylthiophene bridge or to the pyrrole heterocycle, which plays the role of donor group. Compound 2 showed a different reactivity behavior in the presence of the Vilsmeier reagent or with tetracyanoethylene (TCNE) giving compounds 4a and 4b functionalized, respectively, at the 2 or on the 3-position of the pyrrole heterocycle. Their optical (linear and first hyperpolarizability), electrochemical, and thermal properties have been examined. Hyper-Rayleigh scattering (HRS) in dioxane solutions using a fundamental wavelength of 1064 nm was employed to evaluate their second-order nonlinear optical properties. Of these systems, thiobarbituric acid derivative 5b functionalized in the thiophene ring exhibits the largest first hyperpolarizability (β=2480×10?30 esu, T convention) compared to the corresponding compound 4c substituted on the pyrrole heterocycle (β=290×10?30 esu, T convention). Good to excellent thermal stabilities were also obtained for push–pull compounds 4 and 5 (270–288 °C). This multidisciplinary study shows that modulation of the optical and electronic properties can be achieved by introduction of the acceptor groups in the thiophene of the arylthiophene bridge. The measured molecular first hyperpolarizabilities and the observed electrochemical behavior are quite sensitive to the position of acceptor group on the heterocyclic system (on the thiophene or on the pyrrole ring) as well as the strength of the acceptor moieties. Moreover, the combination of their good nonlinearity and high thermal stability make them good candidates for second-order nonlinear optical applications.  相似文献   

14.
The preparation of a series of complexes of the types [RhCl(CO)2(L)], [RhCl(cod)(L)] and [Rh(cod)(L)2]ClO4, where L is a ligand incorporating a ferrocenyl group and a pyridine ring is described. Complexes were characterized using NMR, IR and electronic spectroscopy. The electrochemical behaviour of the complexes was examined using cyclic voltammetry. The X-ray structures of three of the complexes, [RhCl(CO)2{NC5H4CNC6H45-C5H4)Fe(η5-C5H5)}], [RhCl(cod)(3-Fcpy)] and [RhCl(cod){3-Fc(C6H4)py}], were determined.  相似文献   

15.
The efficient procedure to prepare novel water-soluble O-succinyl-chitosan was established by using one three-step reaction. Phthaloyl group was firstly chosen as the protection group for the amino group of chitosan, and O-succinylation was then completed. Protection group was removed finally by using hydrazine hydrate. The chemical structure of the modified chitosan was characterized by FTIR, 1H-NMR, 13C-NMR and elemental analysis. Some physical properties were analyzed by X-ray diffraction, differential scanning calorimetry (DSC), thermogravimetry (TG) and solubility test. It indicates that after O-succinylation, the modified chitosan shows much better solubility in water. The study of enzymatic degradation showed that the O-succinyl-chitosan was of low susceptibility to lysozyme. O-succinylation-chitosan is a useful intermediate, which permits further chemical modification for amino group and may be have potential applications in biomedical system.  相似文献   

16.
A new IL-supported diol,1-(2,3-dihydroxypropyl)-3-methylimidazolium hexafluorophosphate has been synthesized and char- acterized by FT-IR,~1H NMR,~(13)C NMR and MS (ESI).Its physical properties such as freezing point,solubility and specific gravity and thermal stability were determined.Synthetic utilities of the resultant diol as a protecting group for aldehydes were also investigated.  相似文献   

17.
施文芳 《高分子科学》2011,29(6):670-683
A series of hyperbranched polyurethane-benzyltetrazoles(H-PBTZs) with different linkage structures were synthesized via the polycondensation of hexamethylenediisocyanate as an A2 type monomer with(4-(1H-tetrazol-5- yl)benzyl)-diethanolamine(TBDEA) as a BB’2 type monomer in the absence of catalyst at different temperatures.The FTIR, and 13C and 1H-NMR spectroscopy were used to characterize the molecular structures of TBDEA and H-PBTZs as well as the counterpart linear polyurethane-benzyltetrazole(L-PBTZ).The molecular composition was determined by the reaction selectivity that the isocyanate group reacted with the hydroxyl group in diethanolamine segment or the active hydrogen atom on tetrazole ring.Raising reaction temperature was propitious to the reaction of isocyanate group with the active hydrogen atom on tetrazole ring.The degrees of branching(DB) for H-PBTZs obtained from the 1H-NMR spectra increased with raising reaction temperature.The wider molecular weight distribution of 1.7-2.9 for H-PBTZs was obtained via GPC analysis.TGA results showed that H-PBTZs had high thermal stability compared with L-PBTZ.  相似文献   

18.
合成了一种新型的β-环糊精联吡啶钌衍生物[β-CD-Ru(bpy)3],采用分子荧光光谱法研究了该衍生物对一系列维生素的包络作用.β-CD-Ru(bpy)3的结构中含有发光活性基团联吡啶钌中心,因此具有良好的荧光特性.当加入与β-环糊精有主客体识别作用的维生素时,β-CD-Ru(bpy)3与维生素之间发生能量转移从而导致主体分子发生荧光猝灭.采用Benesi-Hildebrand方程,根据其猝灭值计算了该衍生物与各种维生素的包络常数.实验结果表明,维生素与β-CD-Ru(bpy)3包络作用大小顺序为维生素B12>维生素K3>维生素C>维生素A.  相似文献   

19.
A new synthetic strategy for the preparation of persistent paramagnetic cyclodextrin-based rotaxanes is described. The method consists in the formation of inclusion complexes between α-cyclodextrin (α-CD) and α,ω-dithiols containing an octamethylene chain covalently trapped by bulky stoppers composed of 2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO) radical fragments. Interaction of α-CD (the bead) and 1,8-octanedithiol (the thread) occurs in aqueous alkaline media and encapsulation is obtained by nucleophilic substitution at both termini of the linear component with a bulky paramagnetic iodide [2,2,6,6-tetramethyl-4-(2-iodoacetamide)piperidine-N-oxyl]. Structure determination of the new [2]rotaxane by 1H NMR is reported and the spectroscopic data are discussed.  相似文献   

20.
A series of β-cyclodextrin (CDs) functionalized graphene nanohybrids have been successfully fabricated utilizing the classical covalent modification methods at different reaction temperatures. It is very interesting that although both CDs and graphene oxide (GO) could he easily decomposed, the effective combination of GO with CDs leads to significantly enhanced thermal stability of graphene derivatives (GO-CDs). Moreover, the introduction of CDs could dramatically improve the dispersibility promotion of our products in both polar/protic and nonpolar/aprotic solvents, which will contribute to the preparation of polymer nanocomposites and increase of their thermal stability. The improved thermal degradation temperatures can be obtained for polyvinyl alcohol after filling with as little as 1 wt.% of the hybrid. The obtained products could be potentially used in heat-retardant or thermal-control materials.  相似文献   

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