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1.
Three rationally designed polar derivatives of diketopyrrolopyrrole consisting of 1,3‐dimethylimidazolium cationic units and benzene, thiophene, or furan rings as π spacers were synthesized and thoroughly studied. The obtained salts are soluble in polar organic solvents and show satisfactory solubility in water, which makes them suitable for the applications in bioimaging. Photophysical measurements revealed that the obtained derivatives are characterized by strong absorption and good fluorescence quantum yields. The corresponding two‐photon properties were also examined and showed that the synthesized salts exhibit large two‐photon absorption cross‐sections reaching 4000 GM (GM=Goeppert‐Mayer unit, 1 GM=10?50 cm4 s photon?1) and very high two‐photon brightness values exceeding 2000 GM. It was demonstrated that these salts can be safely applied in two‐photon fluorescence microscopy for selective staining of mitochondria in living cells.  相似文献   

2.
Water-soluble PEGylated lignin polymers were efficiently synthesized by macromolecular azo coupling reaction between alkali lignin and PEG based macromolecular diazonium salts in alkaline water.  相似文献   

3.
A new and efficient synthetic route to hydroxymethylated-3,4-ethylenedioxylthiophene(EDOT-MeOH) was developed by a simple four-step sequence,and its global yield was approximately 41.06%.The poly(hydroxymethylated-3, 4-ethylenedioxylthiophene)(PEDOT-MeOH) film was electrosynthesized in aqueous sodium dodecylsulfate micellar solutions and characterized by different methods.The EDOT-MeOH possessed better water solubility,and lower onset oxidation potential than EDOT.The as-obtained PEDOT-MeOH film displayed good reversible redox activity,stability and capacitance properties in a monomer-free electrolyte,especially the good solubility of PEDOT-MeOH film in strong polar organic solvents such as dimethyl sulfoxide and tetrahydrofuran created a potential application in many different fields. Fluorescent spectra indicated that PEDOT-MeOH was a yellow-green-light-emitter with maximum emission at 568 nm.The as-formed PEDOT-MeOH film had good biocompatibility and was used for fabricating the electrochemical vitamin C biosensor.The proposed biosensor showed a linear range of 3×10-6 mol/L to 1.2×10-2 mol/L with the detection limit of 1μmol/L,a sensitivity of 95.6μA(mmol/L)-1 cm-2,and a current response time less than 10 s and a fairly good stability (The relative standard deviation was 0.43%for 20 successive assays,the proposed biosensor still retained 93.5%of bioactivity after 15 days storage.This result indicated that the prepared PEDOT-MeOH film as immobilization matrix of biologically-active species could be a promising candidate for the design and application of biosensor.  相似文献   

4.
李效玉 《高分子科学》2011,29(3):300-307
Epoxy-terminated hyperbranched polymers(EHBPs)were prepared by proton transfer polymerization and characterized by FT-IR,~1H-NMR and GPC.The solution and thermal properties of the uncured samples and mechanical properties of cured samples were examined.The thermo-stable products had good solubility in polar solvents,low solution viscosity and T_gs ranging from 15℃to 33℃depending on their molecular weights.The mechanical properties of cured films were studied and compared with those of a bisphenol-A type epoxy resin.The films of EHBPs had good impact resistance and high gloss values without sacrificing hardness and adhesion.  相似文献   

5.
Silicon-containing polyamides and polyesters of a new type have been synthesized. They contain phenoxasilin rings with double-stranded structure. The polymers were synthesized by the interfacial polycondensation of 2,8-dichloroformyl-10,10-diphenylphenoxasilin with diamines and bisphenols, and were obtained in nearly quantitative yields. Their reduced viscosities were in the range of 0.53–1.47 dl g?1 m dimethylformamide (DMF), m-cresol or chloroform. Some of the polyamides were soluble in polar aprotic solvents such as DMF and N-methyl-2-pyrrolidone (NMP) and the polyesters had good solubility in chloroform, phenol-sym tetrachloroethane (60:40 by wt %) and acidic solvents (m-cresol and nitrobenzene). The polymers hardly dissolved in cone. H2SO4 and some of them coloured in it. Only the polyester having sulphide bonds was soluble in benzene in addition to the above organic solvents. These polymers hardly degraded below 400° except for the polyamides derived from aliphatic diamines. The polymers from aliphatic diamines melted at 290–325°; the other polyamides and the polyesters decomposed without melting.  相似文献   

6.
To prepare novel polyimides with enhanced thermal stability and high solubility in common organic solvents, diamine monomers, 4‐aryl‐2,6 bis‐(4‐amino phenyl)pyridine, were introduced. The diamines were reacted with three different conventional aromatic dianhydrides including pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, and hexafluoroisopropylidene‐2,2‐bis(phthalic‐dianhydride) (6FDA) in dimethylacetamide solvent to obtain the corresponding polyimides via the polyamic acid precursors and chemical imidization. The monomers and polymers were characterized by Fourier transform infrared spectroscopy, 1H NMR, mass spectroscopy, and elemental analysis; and the best condition of polymerization and imidization were obtained via the study of model compound. The polyimides showed little or no weight loss by thermogravimetric analysis up to 500 °C, and those derived from 6FDA exhibited good solubility in various polar solvents. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3826–3831, 2001  相似文献   

7.
The thermodynamic functions free energy, enthalpy, and entropy of solution, were evaluated from solubility data of benzocaine determined at several temperatures in octanol, water, and the mutually saturated solvents, in isopropyl myristate, water, and the mutually saturated solvents, and in cyclohexane. In aqueous media the solubility was determined at pH 7.4 and ionic strength 0.15 mol-L–1. The excess free energy and the activity coefficients of the solutes also were determined. The solubility was higher in organic media, such as octanol and isopropyl myristate, than in aqueous media and cyclohexane.  相似文献   

8.
The thermodynamic functions free energy, enthalpy, and entropy of solution, were evaluated from the solubility data of acetanilide, acetaminophen, and phenacetin, determined at several temperatures in water, octanol, isopropyl myristate, and chloroform. These three organic solvents mutually saturated with water, and finally, in cyclohexane. In the aqueous media, the solubility was determined at pH 7.4 and ionic strength 0.15?mol?L?1. The excess free energy and the activity coefficients of the solutes were also determined. The solubility for acetanilide and phenacetin was higher in organic media such as octanol and chloroform than is those obtained in the aqueous media and cyclohexane, while for acetaminophen the solubility was higher in octanol than those obtained in the other solvents.  相似文献   

9.
Novel dendritic compounds G1.5(OH)4 and G1.5(OH)8 with peripheral hydroxyl were synthesized under mild conditions from cyanuric chloride, ethylene diamine, ethanolamine and diethanolamine. The products could be separated and purified through dispersion and precipitation in organic solvents with good yields (over 93.0%) and high purity (above 98.0%, HPLC). The structures of the products were characterized by IR, MS, 1 H NMR and elementary analysis. G1.5(OH)4 and G1.5(OH)8 could be dissolved in polar solvents such as methanol, water and dimethylsulfoxide. TGA analysis showed that G1.5(OH)4 and G1.5(OH)8 had good thermo stability. The aqueous solutions of G1.5(OH)4 and G1.5(OH)8 exhibited low surface tension.  相似文献   

10.
A solution polyaddition procedure was applied to prepare furanic polyacylsemicarbazides based on 2,2′-isopropylidene-bis(5-(2-furoyl) hydrazide) and aliphatic or aromatic diisocyanates. Model compounds were prepared to facilitate the synthesis and the characterization of the polymers. A systematic study of reaction parameters (the nature of the organic phase, the temperature, the reaction time, and the concentration of monomers) was carried out. High MW polymers were obtained after 12 h reaction at 20°C with 0.2 M monomer solutions in dimethylacetamide. In fact, the polyacylsemicarbazides obtained had inherent viscosities ranging from 0.63 to 0.85 dL/g. There showed good solubility in aprotic polar solvents. The 1H and 13C-NMR spectra were consistent with the expected structures. These furan-based polyacylsemicarbazides are thermally stable up to 290°C, but exhibit a complex thermal behavior. This was explained by the cyclohydration of acylsemicarbazide groups into NH-substituted oxadiazoles, resulting in rigid and high melting polymers, less stable, however, than conventional aromatic polyoxadiazoles.  相似文献   

11.
Solvent extraction of137Cs,86Rb and42K by dipicrylaminate and tetraphenyl borate into nitrobenzene was studied from solutions containing various solvents miscible with water. In all cases the distribution ratios of alkali metals were lower in mixed solutions than in water. In discussing the results, water structure, ion-association, solubility of Cs(I) ionpairs, ionic strength, and organic phase effects were taken into account. Part III in the series Solvent Extraction of Ion-pairs. Part II. Ref.8  相似文献   

12.
Polyformals of fluoro-, nitramine-, and C-nitrodiols show widely differing properties with respect to glass transition temperature, melting transition, and solubility. Polymers with desirable combinations of these properties, e.g., low Tg, high nitro content, and good solubility in polar solvents, were expected to result from acid-promoted copolycondensation of appropriate mixtures of diols with formaldehyde. A series of such condensations were carried out and the polymers obtained from binary mixtures of fluoro- and nitrodiols, different nitrodiols, and fluoro- or nitrodiols and carboranediols, were characterized by GPC, 1H-NMR, and DSC analysis.  相似文献   

13.
Organoiron polynorbornene containing arylazo or hetarylazo dye chromophores has been prepared via ring opening metathesis polymerization using Grubbs' catalyst. The obtained polymers were isolated as brightly colored materials and displayed good solubility in polar organic solvents. The colors of these polymers were affected by the nature of the incorporated azo chromophores. Thermogravimetric analysis of these materials showed that the cleavage of the cyclopentadienyliron (CpFe+) moieties was between 225 and 231 °C, while the degradation of the polymer backbones occurred between 400 and 450 °C. UV-vis studies in DMF showed that the organoiron polymers containing arylazo dyes exhibit wavelength maxima around 425 nm. However, the replacement of these arylazo moieties with hetarylazo dyes displayed substantial bathochromic shifts in the λmax values (≈ 511 nm).  相似文献   

14.
A new series of copolymers was synthesized through the oxidative polymerization of pyrrole (PY) and o‐phenetidine (PHT) with inorganic oxidants in acidic media. The polymerization parameters including the mixing method of the oxidant with the comonomer, the comonomer ratio, the time, the temperature, the oxidant, the organic medium, and the acid were systematically optimized for the synthesis of copolymers with high yields, intrinsic viscosities, and solubility. The resultant copolymers were characterized by elemental analysis, infrared, ultraviolet–visible, solution high‐resolution 1H NMR and solid‐state high‐resolution 13C NMR, circular dichroism spectroscopy, and cyclic voltammetry. The results showed that the PY observed content in the copolymers was much higher than the PY feed content. The regular variation of the polymerization yield, intrinsic viscosity, solubility, macromolecular structure, and electroactivity of the resulting polymers with the comonomer ratio, together with the complete solubility of a PY/PHT (10/90) polymer in highly polar solvents, indicated the formation of real random copolymers containing both PY and PHT units rather than a mixture of two homopolymers. However, the polymers containing more than 59 mol % PY were not homogeneous copolymers consisting of soluble and insoluble parts. A semiquantitative relationship between the polymerization yield or solubility of the copolymers and the polarity index of the organic solvents was examined. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2073–2092, 2004  相似文献   

15.
A series of imidazolium-based symmetrical and asymmetrical dicationic ionic liquids (DcILs) with alkyl spacers of different length and with [FeCl3Br] as counter ion have been synthesized. The synthesized DcILs are characterized by using FTIR and Raman spectroscopy as well as mass spectrometry, along with single-crystal XRD analysis. Physicochemical properties such as solubility, thermal stability and magnetic susceptibility are also measured. These compounds show low melting points, good solubility in water and organic solvents, thermal stability, and paramagnetism. The products of molar susceptibility and temperature (χmol⋅T) for the synthesized DcILs have been found between 4.05 to 4.79 emu mol−1 K Oe−1 and effective magnetic moment values have also been determined to be compared to that expected from the spin-only approximation.  相似文献   

16.
Superacidification of aromatic sulfoxides effects the electrophilic substitution reaction of the resulting hydroxysulfonium ions onto aromatic rings with the elimination of H2O at room temperature. The product, the alkyldiarylsulfonium ion, allows the synthesis of alkylsulfonio-bridged (λ4-alkylsulfanyliumdiyl) aromatic polymers. High molecular-weight poly(alkylsulfonioarylene) salts have been made accessible by the regioselective condensation of aryl sulfoxides. Polymers having a wide variety of structural dimensionalities such as linear, hyper-branched and ladder-type structures can be prepared by this method, which possess interesting properties such as good solubility in polar organic solvents and sometimes even in H2O, susceptibility to nucleophiles to provide thioarylene derivatives, photo-degradability, and electric semiconductivity based on a 3d-2p interaction in aryl sulfonium ion.  相似文献   

17.
18.
A new synthetic route based on the stepwise functionalisation of fullerene cages allows the facile formation of linear, diastereomerically pure triads incorporating two different fullerene cages linked by an organic spacer group. The critical coupling step of two fullerene cages via activation by N,N′-dicyclohexylcarbodiimide was systematically investigated to reveal that the yield of the coupling is maximised in o-dichlorobenzene at high concentrations of the reactant fullerene nucleophile, while in more polar solvents or at lower concentrations of reactants the formation of unwanted side-products (such as guanidine-, N-acylurea- and anhydride-functionalised fullerenes) is favoured. The resultant triads possess an atypically good solubility for this class of compound, which enabled full detailed characterisation by 1H and 13C NMR, IR and UV–vis spectroscopies and by MALDI-TOF mass spectrometry.  相似文献   

19.
A series of poly(pyridinium salt)s-fluorene main-chain ionic polymers with various organic counterions were synthesized by using ring-transmutation polymerization and metathesis reactions. Their chemical structures were characterized by Fourier Transform Infrared (FTIR), proton (1H), and fluorine 19 (19F) nuclear magnetic resonance (NMR) spectrometers. These polymers showed a number-average molecular weight (Mns) between 96.5 and 107.8 kg/mol and polydispersity index (PDI) in the range of 1.12–1.88. They exhibited fully-grown lyotropic phases in polar protic and aprotic solvents at different critical concentrations. Small-angle X-ray scattering for one polymer example indicates lyotropic structure formation for 60–80% solvent fraction. A lyotropic smectic phase contains 10 nm polymer platelets connected by tie molecules. The structure also incorporates a square packing motif within platelets. Thermal properties of polymers were affected by the size of counterions as determined by differential scanning calorimetry and thermogravimetric analysis measurements. Their ultraviolet-visible (UV-Vis) absorption spectra in different organic solvents were essentially identical, indicating that the closely spaced π-π* transitions occurred in their conjugated polymer structures. In contrast, the emission spectra of polymers exhibited a positive solvatochromism on changing the polarity of solvents. They emitted green lights in both polar and nonpolar organic solvents and showed blue light in the film-states, but their λem peaks were dependent on the size of the counterions. They formed aggregates in polar aprotic and protic solvents with the addition of water (v/v, 0–90%), and their λem peaks were blue shifted.  相似文献   

20.
N,N′-bis((2-hydroxyphenyl)(phenyl)methylidene)propane-1,2-diaminato-N,N′,O,O′)-(nitrato-O)-manganese(III) methanol solvate ([Mn(C29H24N2O2)(NO3)CH3OH]) was synthesized and characterized by FTIR, UV–Vis, TG–FTIR, TG/DSC, molar conductivity, magnetic moment measurement and single crystal X-ray analysis. In the structure, the Mn(III) ion adopts a distorted octahedral geometry with two nitrogen and two oxygen atoms from the Schiff base ligand in the equatorial plane, and the nitrate ion and methanol molecule in the axial position. The effects of organic solvents of various polarities on the UV–Vis spectra of the ligand and complex were investigated. The manganese(III) complex is easily dissolved in organic polar aprotic solvents and has moderate solubility in organic polar protic solvents.  相似文献   

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