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1.
IntroductionSince the firstreport in1 990 of the electro- lu-minescence of the conjugated polymers in the filmof poly(p- phenylenevinylene) sandwiched betweenan anode and a cathode of appropriate work func-tions[1] ,enormous efforts have been devoted to thesynthesis of light emitting polymers[2— 4 ] .Owing toconjugated polymers′ photoluminescence and elec-troluminescence having been found out,their im-portant properties,polymer processability,bandgap tunability and mechanical flexibility mak…  相似文献   

2.
IntroductionSince the first report,in 1 990 ,of the electro-luminescence of the conjugated polymers in the filmof poly(p- phenylenevinylene) (PPV) sandwichedbetween an anode and a cathode of appropriatework functions[1] ,enormous efforts have been de-voted to the synthesis of light emitting poly-mers[2— 4 ] .Having been found potential applicationof conjugated polymers in photoluminescence(PL)and electro- luminescence (EL ) ,their importantproperties,polymer processability,band gap tun-abil…  相似文献   

3.
The effects of replacement on the optical properties of diketopyrrolopyrrole(DPP)-based polymers were discussed through replacing the thieno[3,2-b]thiophene units by thiophene units.It is easy to see that the role of replacement would lead to blue shift of steady-state absorption spectrum when thieno[3,2-b]thiophene units is replaced by thiophene units.Meanwhile,the transient absorption data indicate that the role of replacement would not change the relaxation mechanism of polymer,but is able to adjust the photo-excitation relaxation rate of polymer.Their intensity-dependent dynamic curves show that the exciton-exciton annihilation(EEA)would participate in the relaxation process when the polymer is in the aggregation.Through comparing the EEA data between the polymers,it is found that the role of replacement would change the spatial distribution of exciton.  相似文献   

4.
IntroductionIn recentyears,there has been a general inter-est in the encapsulation of inorganic particles withorganic polymers[1] . This kind of composite parti-cles consists of an inorganic core and a polymershell[2 ] .The aim of the encapsulation is to improvethe physical properties of products,and to meetthe development of new materials having a highfunctionality in the fields such as biology,medicine,pharmacology and electronics etc.[3 ,4 ] .The encapsulation of oxide nanoparticles witha p…  相似文献   

5.
Four new 2D donor–acceptor conjugated polymers were designed and synthesized.These new polymers comprised fluorenealt-triphenylamine or carbazole-alt-triphenylamine as the backbones,and pendants with 2,1,3-benzothiadiazole(BT)or naphtho[1,2-c:5,6-c]bis[1,2,5]thiadiazole(NT)in a triphenylamine unit as the side groups.By changing the acceptor BT for a stronger electron-withdrawing unit of NT moiety in the side chain,the energy levels,absorption spectra,band gaps,and charge-transport abilities of the resultant polymers could be effectively tuned.Bulk heterojunction solar cells with these polymers as the electron donors and(6,6)-phenyl-C71-butyric acid methyl ester as the electron acceptor exhibited high open-circuit voltage(more than 0.8 e V).The power conversion efficiency can be improved from 1.37%to 3.52%by replacing the BT with an NT moiety,which indicates that introducing NT as the side-chain building block can be an effective strategy to construct efficient 2D conjugated polymers for PSCs.  相似文献   

6.
Two molecularly imprinted polymers binding to analgesic acetanilide were prepared using either dual functional monomers of calix[4]arene derivative and acrylamide or single monomer acrylamide, respectively. The polymers were ground, sieved and investigated by equilibrium binding experiment to evaluate their recognition properties for the template and other substrates. Scatchard analysis showed that homogeneous recognition sites were formed in the imprinted polymer matrix. Our results demonstrated that the polymer using two functional monomers exhibited better selectivity for the template. This study may open new frontiers for the development and application of imprinted polymers, such as drug separation and purification.  相似文献   

7.
CHO  Iwhan  PYUN  Kwang-Soo 《应用化学》2001,18(5):296-300
In recent years certain new technologies demand optically transparent high Tgpolymer materials.Some aliphatic polymers containing cyclic structure are in the marketalready and have been applied to manufacture various devices in optics industry.However,these polymers are usually of nonpolar character and their difficulties inadhesion and solubility in solvents limited their applicability in many technologies[1 ,2 ] .The polymerization of polar group-containing internal cyclic olefins by transit…  相似文献   

8.
1 INTRODUCTION Inorganic coordination polymers or solid-state po- lymers have received considerable attention in the past few years due to their possible applications as new materials in catalysis, adsorption, ion exchange, separation, magnetic devices, etc.[1] Metal coordina- tion polymers containing dicarboxylate ions as the organic spacer have been the subject of particular interest due to their fascinating architectures and ad- vantageous properties, such as bulk magnetic beha- vior, h…  相似文献   

9.
1. INTRODUCTION Biodegradable polymers have received considerable attention in the last two decades due to their potential applications in the fields related to human life such as environmental protection and ecology. According to the difference in the preparation methods, biodegradable polymers can be classified into two types. One is the biosynthetic polymers, such as bacterialpolyhydroxyalkanoates (PHAs). Among them, the most extensively studied biodegradable thermoplastic polymers ar…  相似文献   

10.
Electrochrometic measurements were carried on the Z-type Langmuir-Blodgett films oftwo liquid crystalline polymers: mono-{6-[4-(phenylazo) naphthyloxy] hexyl} (1a) andmono-{6-[4-(anthraquinone-1-azo) naphthyloxy] hexyl} (2a) ester of polymaleic acid. Itwas found that for both polymers, poling fields parallel and antiparalle1 to dipole momentsof the polymer side chains induce red and blue shift in absorption bands, respectively. Forpolymer la blue shift is accompanied by absorbance increase, while red shift by absorbancedecrease;but for polymer 2a only decrease in absorbance is observed. A simple model wasproposed to analyze the results.  相似文献   

11.
Zhang  Zichao  Liu  Qingqing  Dong  Huanli  Hu  Wenping 《中国科学:化学(英文版)》2019,62(10):1271-1274
<正>The discovery and development of conductive polymers in the 1970 s by Alan J. Heeger, Alan G. Mac Diarmid and Hideki Shirakawa opens the new research field of organic electronics. Over the past decades, conjugated polymers and their applications in various electronic and optoelectronic devices have received considerable attention and studies due to their unique advantages of low cost fabrication methods and mechanical flexibility [1]. With the development of new conjugated polymer materials(to date, maybe hundreds of semiconducting polymers have been synthesized [2,3]) sig-  相似文献   

12.
Polyamides containing thieno[2,3-b]thiophene moiety were prepared via a simple polycondensation reaction of the diaminothieno[2,3-b]thiophene monomer 1 a with different kinds of diacid chlorides(including oxalyl, adipoyl, sebacoyl, isophthaloyl,terephthaloyl, 4,4′-azodibenzoyl, 3,3′-azodibenzoyl, p-phenylene diacryloyl) in the presence of Li Cl and NMP as a solvent through lowtemperature solution polycondensation. The chemical structures of model compound and synthesized polyamides were confirmed by FTIR, nuclear magnetic resonance spectroscopy(including ~1H-NMR and ~(13)C-NMR) and elemental analysis. In addition, the thermal stability, crystallinity structure and surface morphology of synthesized polyamides were characterized via thermogravametric analysis(TGA), wide-angle X-ray diffraction analysis(WAXD) and scanning electron microscopy(SEM). Also, the corrosion inhibition behavior of selected examples of polyamides was investigated; the inhibitive effect of the investigated polymers for carbon steel in 1.0 mol·L~(-1) HCl was studied using potentiodynamic polarization(PDP) and electrochemical impedance spectroscopy(EIS) methods. PDP results displayed that the polyamides containing thieno[2,3-b]thiophene moiety can be as mixed-type inhibitors. The inhibition efficiency(P, %) was found to be in the range from 67.13% to 96.01%. There is an increase in P by the synthesized polymers in comparison to the starting monomer.The adsorption of these polymers was found to obey Langmuir adsorption isotherm.  相似文献   

13.
Thieno[3,2-b]thiophene(TT)monomers end-capped with 3,4-ethylenedioxythiophene(EDOT)moieties are electropolymerized to formπ-conjugated polymers with distinct electrochromic(EC)properties.Steric and electronic factors(electron donor and acceptor substituents)in the side groups of the TT core,as well as the structure of the polymer backbone strongly affect the electrochemical and optical properties of the polymers and their electrochromic characteristics.The studied polymers show low oxidation potentials,tunable from-0.78 to+0.30 V(vs.Fc/Fc~+)and the band gaps from 1.46 to 1.92 eV and demonstrate wide variety of color palettes in polymer films in different states,finely tunable by structural variations in the polymer backbone and the side chains.EC materials of different colors in their doped/dedoped states have been developed(violet,deep blue,light blue,green,brown,purple-red,pinkish-red,orange-red,light gray,cyan and colorless transparent).High optical contrast(up to 79%),short response time(0.57-0.80 s),good cycling stability(up to 91%at 2000 cycles)and high coloration efficiency(up to 234.6 cm2C~(-1))have been demonstrated and the influence of different factors on the above parameters of EC polymers have been discussed.  相似文献   

14.
Supramolecular polymers constructed by orthogonal self-assembly based on multiple hydrogen bonding and macrocyclic host-guest interactions have received increasing attention due to their elegant structures,outstanding properties,and potential applications.Hydrogen bonding endows these supramolecular polymers with good adaptability and reversibility,while macrocyclic host-guest interactions give them good selectivity and versatile stimuli-responsiveness.Therefore,functional supramolecular polymers fabricated by these two highly specific,noninterfering interactions in an orthogonal way have shown wide applications in the fields of molecular machines,electronics,soft materials,etc.In this review,we discuss the recent advances of functional supramolecular polymers fabricated by orthogonal self-assembly based on multiple hydroge n bonding and host-guest interactions.In particular,we focus on crown ether-and pillar[n]arene-based supramolecular polymers due to their compatibility with multiple hydrogen bonds in organic solution.The fabrication strategies,interesting properties,and potential applications of these advanced supramolecular materials are mainly concerned.  相似文献   

15.
IntroductionLinear bidentate N,N′- donor complexes havebeen extensively used in recent years to obtain thepolymeric frameworks with potential applicationprospects in different areas of material sciences,such as electrical conductivity[1] ,magnetism[2 ] ,photomechanical behaviour[3 ] and catalysis[4~ 6] .Among them,4,4′- bipyridine( bpy) has beenproven to be able to form one- dimensional poly-mers[7] ,two- dimensional layers[4] ,and three- di-mensional frameworks exhibiting the interpene-tra…  相似文献   

16.
1 INTRODUCTION Much attention has been paid to 1D, 2D and 3D coordination polymers because they can meet the need of functional materials with desired structures and properties[1~5]. One strategy in the design and synthesis of coordination architectures is the buil- ding-block approach. Commonly, bi- or multidentate organic ligands containing N[6, 7] or O[8, 9] atoms have ever been used in the construction. In our cur- rent work, we have selected melamine ligand as the main building bl…  相似文献   

17.
Electrochemical polymerization of 3-fluoroalkoxy and 3-fluoroether thiophenes givespolymers with relatively high molecular weights and good processibility. Investigationof these polymers by means of GPC indicates that an increase in the number of fluorineatoms in the fluorinated group results in a decrease in degree of polymerization of thepolymers in the same polythiophene series. As shown by NMR and FTIR, the polyfluo-rinated group substituted polythiophenes have regular 2, 5-coupling in their main chains.The SEM micrographs of the polymer films exhibit that polymer (1)-poly [3-2, 2, 3, 3-tetrafluoro-propoxy) thiophene] possesses more regular structure than the other polymersdo. Substitution of polythiophenes by fluorinated groups leads to the polymers with highelectric, electrochemical and thermal stability.  相似文献   

18.
Conjugated polymers can be the alternatives to metals to manufacture the integrated circuit in nano/micro electromechanical systems (NEMS/ MEMS)[1], while patterning is the basis for such an application. It has been well known that the electro-deposition on a template[2—10] represents the simplest method to construct a patterned conducting polymer structure as compared with the conventional ap-proaches such as photolithography, e-beam writing, screen-printing, and ink-jet printing[11]. For…  相似文献   

19.
Ten α,α,α′-trisubstituted cyclododecanones were synthesized and characterized by elemental analyses, infrared, 1^H NMR and 13^C NMR spectra, and X-ray diffraction. NMR data could not give conformational information clearly, but some of their ring skeleton conformations of cyclododecanone moiety were showed to remain the unchanged [3333]-2-one conformation with little distortion, while the others were changed to the [3324]-2-one conformation in their crystal structures. These are consistent with the results of molecular mechanics calculation with Sybyl 6.9 software and Tripos force field, and semi-empirical quantum calculation with AM 1 method in Gaussian 98 software. Two geminal substituting groups are located at α-corner carbon atom, and the third group is at α-side-exo carbon atom in both conformations. Both [3333]-2-one and [3324]-2-one conformations are present in a dynamic equilibrium in the solution, but only one preferred conformation exists in the crystal solid.  相似文献   

20.
Poly(phenylacetylene)s beating monosaccharide pendant groups are synthesized in high yields by [Rh(nbd)Cl]2 catalyst. The polymers have high molecular weights and give satisfactory spectroscopic data corresponding to their molecular structures. They are thermally quite stable (≥ 300℃) and show strong circular dichroism signals in the visible spectral region owing to the helicity of the polyene backbone. The monosaccharide-containing polyacetylenes are cytophilic and can stimulate the growth of living cells.  相似文献   

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