Two novel organic small molecule donor materials(FLU),TDPP and(DFLU)_(2)TDPP based on diketopyrrolopyrrole-fluorene were designed and synthesized successfully.The D-D-π-A-π-D-D type molecule(DFLU)_(2)TDPP was constr...Two novel organic small molecule donor materials(FLU),TDPP and(DFLU)_(2)TDPP based on diketopyrrolopyrrole-fluorene were designed and synthesized successfully.The D-D-π-A-π-D-D type molecule(DFLU)_(2)TDPP was constructed based on the D-π-A-π-D type molecule(FLU)_(2)TDPP by a backbone extension strategy.The optical absorption,electrochemistry and photovoltaic properties of the two novel materials were investigated in detail.Both(FLU)_(2)TDPP and(DFLU)_(2)TDPP show narrow energy gaps of1.71 and 1.64 eV,respectively.Compared to(FLU)_(2)TDPP,the photovoltaic device based on(DFLU)_(2)TDPP/PC_(71)BM exhibited a higher power conversion efficiency of 2.27%due to its excellent optical absorption,narrow band gap and balanced carrier mobility.This study indicates that skeleton extension strategy is an effective strategy to broaden the molecular absorption range and improve device performance.展开更多
This paper describes the procedures for the facile synthesis of 9,9′-bis(methoxymethyl)fluorene using fluorene as starting material. By hydroxymethylation and etherification reaction, the fluorene can be converted to...This paper describes the procedures for the facile synthesis of 9,9′-bis(methoxymethyl)fluorene using fluorene as starting material. By hydroxymethylation and etherification reaction, the fluorene can be converted to desired products with high yield and purity. The optimum conditions of the synthetic procedures were determined. For hydroxymethylation, the reaction temperature was 13 ℃and the mole ratio of sodium methoxide to paraformaldehyde was 0.26; and for etherification, the reaction temperature was 40 ℃and the reaction time was 15 h. Under the optimum conditions, an overall yield of 580 0 and purity of 99.20 0 were obtained.展开更多
Several series of fluorene-based light-emitting polymers with the emphasis on achieving efficient and stable bluelight emission are reported. Spiro-functionalization may narrow the emission spectra (with smaller tail ...Several series of fluorene-based light-emitting polymers with the emphasis on achieving efficient and stable bluelight emission are reported. Spiro-functionalization may narrow the emission spectra (with smaller tail at Ionger wavelengths)of fluorene homopolymers to provide purer blue emission. The thermal spectral stability of the polymers could also beimproved because of the elevation of the glass transition temperature caused by the spiro-functionalization. However, theexcimer emission in fluorene homopolymers is not suppressed by the spiro-functionalization. Alternate copolymers of 9,9-dihexylfluorene and substituted phenylenes may emit efficient blue ligh both in solution and in film. The optical propertiesare dependent on the substituion on the phenylene ring. The alkoxy-substituted polymers displayed efficient PL and EL andgood thermal spectral stability. The HOMO and LUMO energy levels of the polymers based on the backbone structure couldbe tuned in a wide range by attaching different functional groups on the phenylene ring. By attaching europium(III) complexat the ends of the side chains in the alternate copolymers, we have demonstrated a new approach to achieving red emissionwith a very narrow spectrum. The copolymers of 9,9-dihexylfluorene and thiophene and bithiophene with differentsubstitutions were also synthesized to study the effect of substitution and regioregularity on the optical and other physicalproperties of the polymers.展开更多
Synthesis of 9,9-bis（buthoxyearbonylethyl） fluorine（C27 H34 04, Mr= 422.54） with butyl acrylate as alkylation reagent and fluorene as starting material has been performed. The crystal structure was measured by usi...Synthesis of 9,9-bis（buthoxyearbonylethyl） fluorine（C27 H34 04, Mr= 422.54） with butyl acrylate as alkylation reagent and fluorene as starting material has been performed. The crystal structure was measured by using the X-ray diffraction method. The crystal belongs to monoclinic, space group P2 （1）/c with parameters as： a=l. 2912（1）nm, b=l. 0974（1）nm, c=1. 7468（1）nm, β=90. 252（2）, V=2. 4752（4）nm^3 , Z=4, Dcacl= 1. 134 g · cm^-3 ,λ=0. 071 073 nm, μ（MoKα） =0. 075mm^-1 , F（000） =912, R=0. 0651 and wR=0. 1475. X-ray analysis reveals that the three fused rings of the fluorene system are almost coplanar and the two ester groups are nearly perpendicular to the fused-ring system, weak CH O hydrogen-bonding connects the molecule into centrosymmetric dimmers展开更多
A diamine(WuFDA) containing vertical rigid non-planar conjugated fluorene moiety and low polarizability group(C―F)was designed and synthesized through three steps of reactions(halogenated reaction, Suzuki coupling re...A diamine(WuFDA) containing vertical rigid non-planar conjugated fluorene moiety and low polarizability group(C―F)was designed and synthesized through three steps of reactions(halogenated reaction, Suzuki coupling reaction, and reduction reaction).Four kinds of high performance functional polyimides(WuFPI-6 F, WuFPI-BP, WuFPI-BT, and WuFPI-PM) were thus prepared by the condensation polymerization of WuFDA with four commercial dianhydride 6 FDA, BPDA, BTDA, and PMDA, respectively. The polyimides exhibited low dielectric constant, excellent thermal stability, outstanding solubility, good film-forming property, and mechanical properties. The dielectric constants of the polyimides were in the range of 2.28-2.88(f = 10~4 Hz). The 5% weight-loss temperatures(Td 5%)in nitrogen were in the range of 555-584 °C, and the glass transition temperatures(T_g) were in the range of 408-448 °C. The weight loss of WuFPI-BP maintaining at 450 and 500 °C for half an hour was only 0.33% and 1.26%, respectively. All the WuFPIs could be dissolved in almost all organic solvents, even chloroform. The tensile strength and tensile modulus of these films were in the ranges of 78.6-85.7 MPa and 3.1-3.2 GPa, respectively. In addition, the polyimides displayed light color with special fluorescent and resistive switching(ON-OFF) characteristics; the maximum fluorescence emission was observed at 422-424 nm in NMP solution and at 470-548 nm in film state. The memory devices with the configuration of indium tin oxide/WuFPIs/aluminum(ITO/WuFPIs/Al) exhibited distinct volatile memory characteristics of static random access memory(SRAM), with an ON/OFF current ratio of 10~5-10~6. These functional polyimides showed attractive potential applications in the field of high performance flexible polymer photoelectronic devices or polymer memory devices.展开更多
A novel fluorene-bridged tetraketone monomer,9,9-bis[(4-benzilyloxy)phenyl]fluorene(FLTK) was synthesized and characterized.The tetraketone was polymerized with various aromatic tetraamines to afford a series of polyp...A novel fluorene-bridged tetraketone monomer,9,9-bis[(4-benzilyloxy)phenyl]fluorene(FLTK) was synthesized and characterized.The tetraketone was polymerized with various aromatic tetraamines to afford a series of polyphenylquinoxalines(PPQs).The obtained polymers were found to be soluble in common organic solvents such as N-methyl-2-pyrrolidone(NMP),chloroform and m-cresol.Flexible and tough PPQ films obtained by spin-casting their NMP solutions exhibited tensile strengths higher than 60 MPa.The films also demonstrated good thermal stability up to 500℃in nitrogen and glass transition temperatures higher than 280℃.In addition,the PPQ films exhibited good hydrolytic stability. High surface and volume resistivity retentions were achieved for the films after immersion or boiling in water for 24 h.展开更多
A novel compound of 10-（3,4-dichlorophenymethylidyne）-9,10-dihydrofluorene （C20H12Cl2, Mr = 323.20） was synthesized via Knoevenagel reaction under microwave irradiation （500 w） within short reaction time （8 min...A novel compound of 10-（3,4-dichlorophenymethylidyne）-9,10-dihydrofluorene （C20H12Cl2, Mr = 323.20） was synthesized via Knoevenagel reaction under microwave irradiation （500 w） within short reaction time （8 min）, giving a high yield of product （87%）. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of monoclinic system, space group P21/c with a = 12.8781（13）, b = 16.5067（16）, c = 7.4656（7）, β = 103.567（2）o, V = 1542.7（3）3, Z = 4, Dc = 1.392 g/cm3, μ = 0.413 mm-1, F（000） = 664, R = 0.0569 and wR = 0.1342 for 3355 observed reflections with I 2σ（I）. The crystal structure involves a conjugated system which shows an olefin structure.展开更多
The solubilities of fluorene in Exxsol D30, Exxsol D40, and crude dimethyl ethylbenzene(DME) from 299.25 to 356.85 K were investigated using the gas chromatography(GC) observation technique. Solubility curves were obt...The solubilities of fluorene in Exxsol D30, Exxsol D40, and crude dimethyl ethylbenzene(DME) from 299.25 to 356.85 K were investigated using the gas chromatography(GC) observation technique. Solubility curves were obtained based on the results and correlated with the modified Apelblat and λh equations to provide a valid model to predict the dissolution thermodynamic properties of fluorene at different temperatures, which is important in separating fluorene by crystallization.展开更多
A series of novel Michael addition products of fluorene to chalcone were obtained in the presence of sodium hydroxide under solvent-free condition. The advantages of this procedure were mild reaction conditions, simpl...A series of novel Michael addition products of fluorene to chalcone were obtained in the presence of sodium hydroxide under solvent-free condition. The advantages of this procedure were mild reaction conditions, simple protocol, and high yields. The structures of the products were characterized by IR, 1H NMR, MS and X-ray diffraction. The crystal of the new compound 3 h is Triclinic, space group P-1 with a = 0.97352（6） nm, b = 1.08918（7） nm, c = 2.58418（16） nm, α = 80.1400（10）°, β = 79.5490（10）°, γ = 64.2440（10）°, V = 2.4137（3） nm3, Z = 4, Dc=1.220 g/cm3,μ = 0.286 mm-1, F（000） = 920, R = 0.0656 and wR = 0.1554 for 5664 observed reflection with I 〉 2σ（I）.展开更多
A novel fluorene derivative containing triphenylamine groups, 2,7-bis[4-（diphe- nylamino）-phenyl]fluorene （C49H36N2, Mr = 652.80）, was synthesized via Suzuki coupling reaction （yield： 19%） and its crystal struc...A novel fluorene derivative containing triphenylamine groups, 2,7-bis[4-（diphe- nylamino）-phenyl]fluorene （C49H36N2, Mr = 652.80）, was synthesized via Suzuki coupling reaction （yield： 19%） and its crystal structure was determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 9.320（4）, b = 11.250（6）, c = 17.369（6） A, a = 88.035（3）, β = 86.450（5）, γ = 73.524（5）°. V= 1742.8（13）A3, Z = 2, Dc = 1.244 g/cm3, p（MoKa） = 0.072 mm-1, F（000） = 688, S = 1.095, the final R = 0.0616 and wR = 0.1878. It presents a linear framework constituted by a linkage of fluorene as a bridge and two triphenylamine groups. Its spectral and electrochemical properties were studied by UV-Vis absorption, fluorescence spectroscopy and cyclic voltammetry （CV）. This compound can emit intense blue fluorescence with a peak wavelength of 446 nm and a full width at half maximum （FWHM） of 38 nm under UV excitation at 350 nm in film. The highest occupied molecular orbital （HOMO） energy level, the lowest unoccupied molecular orbital （LUMO） energy level and optical band gap （Eg） of the title compound are -5.46, -2.57 and 2.89 eV, respectively.展开更多
Novel poly（aryl ether sulfone ketone）s （PAESK） were synthesized from bisphenol A （BPA）, 9,9＇-bis（4-hydroxyphenyl） fluorene （BHPF）, 4,4＇-dichlorodiphenylsulfone （DCS） and 4,4＇-difluorobenzophenone （DFB...Novel poly（aryl ether sulfone ketone）s （PAESK） were synthesized from bisphenol A （BPA）, 9,9＇-bis（4-hydroxyphenyl） fluorene （BHPF）, 4,4＇-dichlorodiphenylsulfone （DCS） and 4,4＇-difluorobenzophenone （DFB） via nucleophilic substitution polymerization, which were subsequently used to fabricate ultrafiltration membrane by phase-inversion method for high temperature condensed water treatment. The obtained high molecular weight co-polymers with fluorene group with good solubility and good thermal stability, can be easily cast into flexible, white and non-transparent fiat films. The influence of molar ratio of BPA and BHPF on the properties of the prepared co-polymers and membranes was investigated in detail. SEM study of the morphology of the membranes indicated that the prepared membranes possessed homogeneous pores on the top surface and were sponge-like or finger-like in cross-section. Pure water flux of the membranes increased from 71.87 L·m-2.h-1 to 247.65 L·m-2.h-1, while the retention of BSA decreased slightly, and the water contact angle decreased from 82.1 ° to 55.6° with the PVP concentration from 0 wt% to 10 wt%. With increasing concentration of PVP, the mechanical properties of membranes decreased, while the thermal stability increased. The permeate flux measurement showed that the PAESK membrane had the potential for high temperature condensed water treatment.展开更多
Geometric structures of 135 polychlorinated fluorene （PCFR） molecules were optimized using density functional theory （DFT） at the B3LYP/6-311G＊＊ level and their thermodynamic properties in the ideal gas state we...Geometric structures of 135 polychlorinated fluorene （PCFR） molecules were optimized using density functional theory （DFT） at the B3LYP/6-311G＊＊ level and their thermodynamic properties in the ideal gas state were calculated. The relations of these thermodynamic properties with the number and position of chlorine atoms were also explored, from which the relative stability of PCFR congeners was theoretically proposed according to the magnitude of the relative standard Gibbs free energy of formation （Δr,fGθ）. The results show that the geometric configuration of PCFR isomers is determined by the position of chlorine atoms. There exist two types of intramolecular weak interactions, i.e., C–H···Cl and Cl···Cl interactions in PCFR molecules. The change of ΔfHθ and ΔfGθ of most stable PCFR isomers with increasing the number of chlorine atoms is different from that in most unstable PCFR congeners. The values of ΔfHθ and ΔfGθ for PCFR isomers with the same number of chlorine atoms strongly depend on the position of chlorine atoms and the relative stability of PCFR congeners is mainly determined by intramolecular delocalized π bond and Cl···Cl nuclear repulsive interaction.展开更多
In this paper, a new D-A copolymer, PFDBCPDT, which consists of benzo-2,1,3-thiadiazole as acceptor units and cyclopentadithiophene and fluorene as donor units, was synthesized. The thermal, electrochemical, photophys...In this paper, a new D-A copolymer, PFDBCPDT, which consists of benzo-2,1,3-thiadiazole as acceptor units and cyclopentadithiophene and fluorene as donor units, was synthesized. The thermal, electrochemical, photophysical and photovoltaic properties of PFDBCPDT were studied. PFDBCPDT showed a low optical band gap of 1.84 eV, and relatively low HOMO level of-5.69 eV. The best device performance was obtained by PFDBCPDT/PC61BM （1：3） with 0.5 vol% DIO. The device exhibited a power conversion efficiency of 3.06%, with a relatively high open circuit voltage of 0.87 eV.展开更多
A series of linear and X-shaped oligo（para-phenylene） derivatives functionalized with fluorene ethynylenes 1,3 and 4 were synthesized through sequent Sonogashira coupling and Suzuki-Miyaura reaction in high yield.Th...A series of linear and X-shaped oligo（para-phenylene） derivatives functionalized with fluorene ethynylenes 1,3 and 4 were synthesized through sequent Sonogashira coupling and Suzuki-Miyaura reaction in high yield.The electron-donating group-OCH3 and electron-withdrawing counterparts-CF3 were introduced to tune the spectra properties of compounds 3 and 4.The detail investigation of their photophysical properties in solution and film indicated that the introduction of both -OCH3 and -CF3 makes maximum emission distinct red-shift in comparison with parent compound 1,but the latter more prominently.展开更多
Copolymers of fluorene-co-phenothiazine （ P1） and th iophene-co-phenothiazine （ P2 ） were prepared respectively by Wittig reaction. The synthesis, photo-physical and electroluminescent properties of the resulting ...Copolymers of fluorene-co-phenothiazine （ P1） and th iophene-co-phenothiazine （ P2 ） were prepared respectively by Wittig reaction. The synthesis, photo-physical and electroluminescent properties of the resulting polymers were analyzed by FT-IR, GPC, IH-NMR, UV-Vis, Photoluminescence （PL）, Electroluminescence （EL） and Cyclic Voltammetry （CV）. Their single layer devices with configuration of lTO/polymers/Ca/Al were studied. GPC results revealed the weight-average molecular weight （Mw） was 3.0×10^3 and 5.4×10^3, respectively. The device with a single layer structure of ITO/P1/Ca/Al emits green light with the maximum peak at 552nm. However, the device with a single layer structure of ITO/P2/Ca/Al emit red light with the maximum peak at 616nm.展开更多
A donor-acceptor type conjugated polymer poly（5,6-bis（octyloxy）-4,7-di（thiophen-2-yl）benzo-[c] [1,2,5]- thiadiazole-9,9-dioctylfluorene） （POTBTF） based on octyloxy-containing benzothiadiazole （OTBT） and octy...A donor-acceptor type conjugated polymer poly（5,6-bis（octyloxy）-4,7-di（thiophen-2-yl）benzo-[c] [1,2,5]- thiadiazole-9,9-dioctylfluorene） （POTBTF） based on octyloxy-containing benzothiadiazole （OTBT） and octyl- containing fluorine （F） was synthesized by Suzuki coupling reaction. The polymer possesses a narrow bandgap and strong light harvesting ability with excellent thermal stability and reasonable solubility. POTBTF exhibited a broad absorption from 300 to 600 nm with an absorption peak at 543.8 nm. The power conversion efficiency of the polymer solar cell based on POTBTF/PC71BM （1：3, w/w） reached 1.77% with a short-circuit current density of 6.69 mA/cm2, an open-circuit voltage of 0.71 V, and a fill factor of 0.374 under AM 1.5 G irradiation （100 mW/cm2） without annealing or any additives. The results indicate that introducing long alkoxy side chains into benzothiadiazole would not only improve the solubility of the polymers but also maintain the planarity of molecule conformation, and therefore, enhance the performance of photovoltaic devices.展开更多
π-Electron coupling of pendant conjugated segment inπ-stacked semiconducting polymers always causes the formation of defect trapped sites and further quenched high-band excitons,which is harmful to the performance a...π-Electron coupling of pendant conjugated segment inπ-stacked semiconducting polymers always causes the formation of defect trapped sites and further quenched high-band excitons,which is harmful to the performance and stability of deep-blue polymer light-emitting diodes(PLEDs).Herein,considerate of“defect”carbazole(Cz)electromers in poly(N-vinylcarbazole)(PVK),a series of fluorene units are introduced into pendant segments(PVCz-DMeF,PVCz-FMeNPh and PVCz-DFMeNPh)to suppress the strongπ-electron coupling of pendant Cz units and enhance radiative transition toward fabricating sable PLEDs.Compared to PVCz-FMeNPh and PVCz-DFMeNPh,PVCz-DMeF spin-coated films show a relatively efficient deep-blue emission,completely similar to its single pendant chromophore,confirmed an extremely weak charge-transfer and electron coupling between adjacent pendant segments.Therefore,PLEDs based on PVCz-DMeF present stable and deep-blue emission with a high color purity(0.17,0.08),associated with extremely weak defect emission at 600∼700nm(induced by carbazole electromers).Finally,PLEDs based on PVCz-DMeF/F8BT blended films(1:1)also present the high maximum luminance(Lmax)of 6261 cd/m2 and current efficiency(CE_(max))of 2.03 cd/A,confirmed slightly trapped sites formation.Therefore,precisely control the arrangement and packing model of pendant units inπ-stacked polymer is an essential prerequisite for building efficient and stable emitter for optoelectronic devices.展开更多
Novel fluorene-based poly(aromatic diacetylene)s have been synthesized by CuCl-catalyzed oxidative coupling of aromatic diynes.New aromatic diynes 2,7-diethynyl-9,9-bis(triphenylamine)fluorene(M_1)is synthesized by mu...Novel fluorene-based poly(aromatic diacetylene)s have been synthesized by CuCl-catalyzed oxidative coupling of aromatic diynes.New aromatic diynes 2,7-diethynyl-9,9-bis(triphenylamine)fluorene(M_1)is synthesized by multistep reactions.The structures and properties of the polymers are characterized and evaluated by IR,NMR,TGA,UV, photoluminescence(PL),and cyclic voltammetry analyses.These polymers possess good thermal stability.All the polymers are completely soluble in coammon solvents such as toluene,THF,c...展开更多
Efficient white light emitting polymers were synthesized based on poly（9,9-dioctylfluorene-co-dibenzothiophene- S,S-dioxide） as blue emitter and a bisphenylamine functionalized 2,1,3-benzothiadiazole （DPABT） as re...Efficient white light emitting polymers were synthesized based on poly（9,9-dioctylfluorene-co-dibenzothiophene- S,S-dioxide） as blue emitter and a bisphenylamine functionalized 2,1,3-benzothiadiazole （DPABT） as red emitter. It was found that the incorporation of hole-transporting carbazole moiety into polymer main chain could effectively reduce the hole injection barriers, which can lead to distinctly improved charge balance in the emissive layer. Additionally, the hole- transporting carbazole units may form efficient bipolar host with electron-transporting dibenzothiophene-S,S-dioxide units. The white light emitting diodes based on single polymer PFSOCzDPABT showed the maximum luminous efficiency of 3.3 cd/A with the maximum luminance of 10282 cd/m2, and the luminous efficiency showed only 24% roll off at current density of 400 mA/cm2. These Commission Internationale d＇Enclairage （CIE） coordinates of the devices changed slightly with the driving voltages increasing from 8 V to 12 V, and were very close to National Television System Committee （NTSC） standard white light emission of （0.33, 0.33）. The results indicated that the incorporating bipolar host and low band gap DPABT unit was a promising way to achieve efficient single white light emitting copolymers.展开更多
A novel functional polyacetylene containing fluorene group as a pendant,poly（2-（p-methylstyrene）-7-acetylene-9,9-dioctyl-fluorene）, was synthesized in moderate yield by[Rh（nbd）Cl]_2-Et_3N catalyst.The structures...A novel functional polyacetylene containing fluorene group as a pendant,poly（2-（p-methylstyrene）-7-acetylene-9,9-dioctyl-fluorene）, was synthesized in moderate yield by[Rh（nbd）Cl]_2-Et_3N catalyst.The structures and properties of monomer and polymer were characterized and evaluated with FTIR,NMR,UV-vis,GPC and Z-scan,respectively.The results show that the incorporation of fluorene into polyacetylene has endowed the resultant polymer with well optical limiting properties for laser at wavelength 780 nm based on two-photon absorption mechanism.展开更多
基金supported by the National Natural Science Foundation of China(21102013)the Fundamental Research Funds for the Central Universities(DUT16ZD205)
文摘Two novel organic small molecule donor materials(FLU),TDPP and(DFLU)_(2)TDPP based on diketopyrrolopyrrole-fluorene were designed and synthesized successfully.The D-D-π-A-π-D-D type molecule(DFLU)_(2)TDPP was constructed based on the D-π-A-π-D type molecule(FLU)_(2)TDPP by a backbone extension strategy.The optical absorption,electrochemistry and photovoltaic properties of the two novel materials were investigated in detail.Both(FLU)_(2)TDPP and(DFLU)_(2)TDPP show narrow energy gaps of1.71 and 1.64 eV,respectively.Compared to(FLU)_(2)TDPP,the photovoltaic device based on(DFLU)_(2)TDPP/PC_(71)BM exhibited a higher power conversion efficiency of 2.27%due to its excellent optical absorption,narrow band gap and balanced carrier mobility.This study indicates that skeleton extension strategy is an effective strategy to broaden the molecular absorption range and improve device performance.
文摘This paper describes the procedures for the facile synthesis of 9,9′-bis(methoxymethyl)fluorene using fluorene as starting material. By hydroxymethylation and etherification reaction, the fluorene can be converted to desired products with high yield and purity. The optimum conditions of the synthetic procedures were determined. For hydroxymethylation, the reaction temperature was 13 ℃and the mole ratio of sodium methoxide to paraformaldehyde was 0.26; and for etherification, the reaction temperature was 40 ℃and the reaction time was 15 h. Under the optimum conditions, an overall yield of 580 0 and purity of 99.20 0 were obtained.
文摘Several series of fluorene-based light-emitting polymers with the emphasis on achieving efficient and stable bluelight emission are reported. Spiro-functionalization may narrow the emission spectra (with smaller tail at Ionger wavelengths)of fluorene homopolymers to provide purer blue emission. The thermal spectral stability of the polymers could also beimproved because of the elevation of the glass transition temperature caused by the spiro-functionalization. However, theexcimer emission in fluorene homopolymers is not suppressed by the spiro-functionalization. Alternate copolymers of 9,9-dihexylfluorene and substituted phenylenes may emit efficient blue ligh both in solution and in film. The optical propertiesare dependent on the substituion on the phenylene ring. The alkoxy-substituted polymers displayed efficient PL and EL andgood thermal spectral stability. The HOMO and LUMO energy levels of the polymers based on the backbone structure couldbe tuned in a wide range by attaching different functional groups on the phenylene ring. By attaching europium(III) complexat the ends of the side chains in the alternate copolymers, we have demonstrated a new approach to achieving red emissionwith a very narrow spectrum. The copolymers of 9,9-dihexylfluorene and thiophene and bithiophene with differentsubstitutions were also synthesized to study the effect of substitution and regioregularity on the optical and other physicalproperties of the polymers.
基金Foundation of Huangshi Institute of Technology(2008yjz27B)
文摘Synthesis of 9,9-bis（buthoxyearbonylethyl） fluorine（C27 H34 04, Mr= 422.54） with butyl acrylate as alkylation reagent and fluorene as starting material has been performed. The crystal structure was measured by using the X-ray diffraction method. The crystal belongs to monoclinic, space group P2 （1）/c with parameters as： a=l. 2912（1）nm, b=l. 0974（1）nm, c=1. 7468（1）nm, β=90. 252（2）, V=2. 4752（4）nm^3 , Z=4, Dcacl= 1. 134 g · cm^-3 ,λ=0. 071 073 nm, μ（MoKα） =0. 075mm^-1 , F（000） =912, R=0. 0651 and wR=0. 1475. X-ray analysis reveals that the three fused rings of the fluorene system are almost coplanar and the two ester groups are nearly perpendicular to the fused-ring system, weak CH O hydrogen-bonding connects the molecule into centrosymmetric dimmers
基金financial support by the National 973 Program of China (No. 2014CB643605)the National Natural Science Foundation of China (Nos. 51373204 and 51873239)+3 种基金the Science and Technology Project of Guangdong Province (Nos. 2015B090915003 and 2015B090913003)the China Postdoctoral Science Foundation (No. 2017M612801)the Leading Scientific, Technical and Innovation Talents of Guangdong Special Support Program (No. 2016TX03C295)the Fundamental Research Funds for the Central Universities (No. 161gzd08)
文摘A diamine(WuFDA) containing vertical rigid non-planar conjugated fluorene moiety and low polarizability group(C―F)was designed and synthesized through three steps of reactions(halogenated reaction, Suzuki coupling reaction, and reduction reaction).Four kinds of high performance functional polyimides(WuFPI-6 F, WuFPI-BP, WuFPI-BT, and WuFPI-PM) were thus prepared by the condensation polymerization of WuFDA with four commercial dianhydride 6 FDA, BPDA, BTDA, and PMDA, respectively. The polyimides exhibited low dielectric constant, excellent thermal stability, outstanding solubility, good film-forming property, and mechanical properties. The dielectric constants of the polyimides were in the range of 2.28-2.88(f = 10~4 Hz). The 5% weight-loss temperatures(Td 5%)in nitrogen were in the range of 555-584 °C, and the glass transition temperatures(T_g) were in the range of 408-448 °C. The weight loss of WuFPI-BP maintaining at 450 and 500 °C for half an hour was only 0.33% and 1.26%, respectively. All the WuFPIs could be dissolved in almost all organic solvents, even chloroform. The tensile strength and tensile modulus of these films were in the ranges of 78.6-85.7 MPa and 3.1-3.2 GPa, respectively. In addition, the polyimides displayed light color with special fluorescent and resistive switching(ON-OFF) characteristics; the maximum fluorescence emission was observed at 422-424 nm in NMP solution and at 470-548 nm in film state. The memory devices with the configuration of indium tin oxide/WuFPIs/aluminum(ITO/WuFPIs/Al) exhibited distinct volatile memory characteristics of static random access memory(SRAM), with an ON/OFF current ratio of 10~5-10~6. These functional polyimides showed attractive potential applications in the field of high performance flexible polymer photoelectronic devices or polymer memory devices.
基金supported by the National Natural Science Foundation of China(Nos.51873104 and 51011120100)
文摘A novel fluorene-bridged tetraketone monomer,9,9-bis[(4-benzilyloxy)phenyl]fluorene(FLTK) was synthesized and characterized.The tetraketone was polymerized with various aromatic tetraamines to afford a series of polyphenylquinoxalines(PPQs).The obtained polymers were found to be soluble in common organic solvents such as N-methyl-2-pyrrolidone(NMP),chloroform and m-cresol.Flexible and tough PPQ films obtained by spin-casting their NMP solutions exhibited tensile strengths higher than 60 MPa.The films also demonstrated good thermal stability up to 500℃in nitrogen and glass transition temperatures higher than 280℃.In addition,the PPQ films exhibited good hydrolytic stability. High surface and volume resistivity retentions were achieved for the films after immersion or boiling in water for 24 h.
基金Supported by the Team Research for Excellent Mid-aged and Young Teachers of Higher Education of Hubei Province (T201006)
文摘A novel compound of 10-（3,4-dichlorophenymethylidyne）-9,10-dihydrofluorene （C20H12Cl2, Mr = 323.20） was synthesized via Knoevenagel reaction under microwave irradiation （500 w） within short reaction time （8 min）, giving a high yield of product （87%）. Its structure was determined by IR, 1H NMR, MS, elemental analysis and X-ray diffraction. The crystal of the new compound is of monoclinic system, space group P21/c with a = 12.8781（13）, b = 16.5067（16）, c = 7.4656（7）, β = 103.567（2）o, V = 1542.7（3）3, Z = 4, Dc = 1.392 g/cm3, μ = 0.413 mm-1, F（000） = 664, R = 0.0569 and wR = 0.1342 for 3355 observed reflections with I 2σ（I）. The crystal structure involves a conjugated system which shows an olefin structure.
文摘The solubilities of fluorene in Exxsol D30, Exxsol D40, and crude dimethyl ethylbenzene(DME) from 299.25 to 356.85 K were investigated using the gas chromatography(GC) observation technique. Solubility curves were obtained based on the results and correlated with the modified Apelblat and λh equations to provide a valid model to predict the dissolution thermodynamic properties of fluorene at different temperatures, which is important in separating fluorene by crystallization.
文摘A series of novel Michael addition products of fluorene to chalcone were obtained in the presence of sodium hydroxide under solvent-free condition. The advantages of this procedure were mild reaction conditions, simple protocol, and high yields. The structures of the products were characterized by IR, 1H NMR, MS and X-ray diffraction. The crystal of the new compound 3 h is Triclinic, space group P-1 with a = 0.97352（6） nm, b = 1.08918（7） nm, c = 2.58418（16） nm, α = 80.1400（10）°, β = 79.5490（10）°, γ = 64.2440（10）°, V = 2.4137（3） nm3, Z = 4, Dc=1.220 g/cm3,μ = 0.286 mm-1, F（000） = 920, R = 0.0656 and wR = 0.1554 for 5664 observed reflection with I 〉 2σ（I）.
基金supported by the National Natural Science Foundation of China (Nos. 20805024, and 20971075)the Foundation of the Education Department of Zhejiang Province (No. Y201016284)+2 种基金the Ningbo Municipal Natural Science Foundation (No. 2010A610146)the research foundation of Ningbo University (No. xkl071)the K. C. Wong Magna Fund in Ningbo University
文摘A novel fluorene derivative containing triphenylamine groups, 2,7-bis[4-（diphe- nylamino）-phenyl]fluorene （C49H36N2, Mr = 652.80）, was synthesized via Suzuki coupling reaction （yield： 19%） and its crystal structure was determined by single-crystal X-ray diffraction. It crystallizes in triclinic, space group P1 with a = 9.320（4）, b = 11.250（6）, c = 17.369（6） A, a = 88.035（3）, β = 86.450（5）, γ = 73.524（5）°. V= 1742.8（13）A3, Z = 2, Dc = 1.244 g/cm3, p（MoKa） = 0.072 mm-1, F（000） = 688, S = 1.095, the final R = 0.0616 and wR = 0.1878. It presents a linear framework constituted by a linkage of fluorene as a bridge and two triphenylamine groups. Its spectral and electrochemical properties were studied by UV-Vis absorption, fluorescence spectroscopy and cyclic voltammetry （CV）. This compound can emit intense blue fluorescence with a peak wavelength of 446 nm and a full width at half maximum （FWHM） of 38 nm under UV excitation at 350 nm in film. The highest occupied molecular orbital （HOMO） energy level, the lowest unoccupied molecular orbital （LUMO） energy level and optical band gap （Eg） of the title compound are -5.46, -2.57 and 2.89 eV, respectively.
基金financial support under Heilongjiang Postdoctoral Fund (No.LBH-Z09175)
文摘Novel poly（aryl ether sulfone ketone）s （PAESK） were synthesized from bisphenol A （BPA）, 9,9＇-bis（4-hydroxyphenyl） fluorene （BHPF）, 4,4＇-dichlorodiphenylsulfone （DCS） and 4,4＇-difluorobenzophenone （DFB） via nucleophilic substitution polymerization, which were subsequently used to fabricate ultrafiltration membrane by phase-inversion method for high temperature condensed water treatment. The obtained high molecular weight co-polymers with fluorene group with good solubility and good thermal stability, can be easily cast into flexible, white and non-transparent fiat films. The influence of molar ratio of BPA and BHPF on the properties of the prepared co-polymers and membranes was investigated in detail. SEM study of the morphology of the membranes indicated that the prepared membranes possessed homogeneous pores on the top surface and were sponge-like or finger-like in cross-section. Pure water flux of the membranes increased from 71.87 L·m-2.h-1 to 247.65 L·m-2.h-1, while the retention of BSA decreased slightly, and the water contact angle decreased from 82.1 ° to 55.6° with the PVP concentration from 0 wt% to 10 wt%. With increasing concentration of PVP, the mechanical properties of membranes decreased, while the thermal stability increased. The permeate flux measurement showed that the PAESK membrane had the potential for high temperature condensed water treatment.
基金supported by the Natural Science Research Program of Henan Provincial Department of Education (No. 2009A150022)the Young Talented Teacher Foundation of Xinyang Normal University
文摘Geometric structures of 135 polychlorinated fluorene （PCFR） molecules were optimized using density functional theory （DFT） at the B3LYP/6-311G＊＊ level and their thermodynamic properties in the ideal gas state were calculated. The relations of these thermodynamic properties with the number and position of chlorine atoms were also explored, from which the relative stability of PCFR congeners was theoretically proposed according to the magnitude of the relative standard Gibbs free energy of formation （Δr,fGθ）. The results show that the geometric configuration of PCFR isomers is determined by the position of chlorine atoms. There exist two types of intramolecular weak interactions, i.e., C–H···Cl and Cl···Cl interactions in PCFR molecules. The change of ΔfHθ and ΔfGθ of most stable PCFR isomers with increasing the number of chlorine atoms is different from that in most unstable PCFR congeners. The values of ΔfHθ and ΔfGθ for PCFR isomers with the same number of chlorine atoms strongly depend on the position of chlorine atoms and the relative stability of PCFR congeners is mainly determined by intramolecular delocalized π bond and Cl···Cl nuclear repulsive interaction.
基金financially supported by the 973 Project(Nos.2009CB623601and2009CB930603)the Science Fund for Creative Research Groups(No.20921061)the National Natural Science Foundation of China(Nos.51173179,20904055 and21074130)
文摘In this paper, a new D-A copolymer, PFDBCPDT, which consists of benzo-2,1,3-thiadiazole as acceptor units and cyclopentadithiophene and fluorene as donor units, was synthesized. The thermal, electrochemical, photophysical and photovoltaic properties of PFDBCPDT were studied. PFDBCPDT showed a low optical band gap of 1.84 eV, and relatively low HOMO level of-5.69 eV. The best device performance was obtained by PFDBCPDT/PC61BM （1：3） with 0.5 vol% DIO. The device exhibited a power conversion efficiency of 3.06%, with a relatively high open circuit voltage of 0.87 eV.
基金Beijing Natural Science Foundation(No.2093033)Scientific Research Project of Beijing Educational Committee(Nos.KM 200910020012 and KM 201010020002) for financial support
文摘A series of linear and X-shaped oligo（para-phenylene） derivatives functionalized with fluorene ethynylenes 1,3 and 4 were synthesized through sequent Sonogashira coupling and Suzuki-Miyaura reaction in high yield.The electron-donating group-OCH3 and electron-withdrawing counterparts-CF3 were introduced to tune the spectra properties of compounds 3 and 4.The detail investigation of their photophysical properties in solution and film indicated that the introduction of both -OCH3 and -CF3 makes maximum emission distinct red-shift in comparison with parent compound 1,but the latter more prominently.
基金Tianjin Natural Sci. Found. (033800311) Key Project of Chinese Ministry of Education (205007)+2 种基金 Sci. Develop. Found. of Tianjin Education Commission (20030426, 20041017, 20050520) the German Federal Ministry for Education and Research (BMBF, CHN 05/011) the National Nature Sci. Found. (60276027) and Tianjin Key Discipline of Mat. Phy. and Chem.
文摘Copolymers of fluorene-co-phenothiazine （ P1） and th iophene-co-phenothiazine （ P2 ） were prepared respectively by Wittig reaction. The synthesis, photo-physical and electroluminescent properties of the resulting polymers were analyzed by FT-IR, GPC, IH-NMR, UV-Vis, Photoluminescence （PL）, Electroluminescence （EL） and Cyclic Voltammetry （CV）. Their single layer devices with configuration of lTO/polymers/Ca/Al were studied. GPC results revealed the weight-average molecular weight （Mw） was 3.0×10^3 and 5.4×10^3, respectively. The device with a single layer structure of ITO/P1/Ca/Al emits green light with the maximum peak at 552nm. However, the device with a single layer structure of ITO/P2/Ca/Al emit red light with the maximum peak at 616nm.
文摘A donor-acceptor type conjugated polymer poly（5,6-bis（octyloxy）-4,7-di（thiophen-2-yl）benzo-[c] [1,2,5]- thiadiazole-9,9-dioctylfluorene） （POTBTF） based on octyloxy-containing benzothiadiazole （OTBT） and octyl- containing fluorine （F） was synthesized by Suzuki coupling reaction. The polymer possesses a narrow bandgap and strong light harvesting ability with excellent thermal stability and reasonable solubility. POTBTF exhibited a broad absorption from 300 to 600 nm with an absorption peak at 543.8 nm. The power conversion efficiency of the polymer solar cell based on POTBTF/PC71BM （1：3, w/w） reached 1.77% with a short-circuit current density of 6.69 mA/cm2, an open-circuit voltage of 0.71 V, and a fill factor of 0.374 under AM 1.5 G irradiation （100 mW/cm2） without annealing or any additives. The results indicate that introducing long alkoxy side chains into benzothiadiazole would not only improve the solubility of the polymers but also maintain the planarity of molecule conformation, and therefore, enhance the performance of photovoltaic devices.
基金supported by the National Natural Science Foundation of China(Nos.22105099 and 61874053)Natural Science Foundation of Jiangsu Province(No.BK20200700)+2 种基金the China Postdoctoral Science Foundation(No.2022M711591)the open research fund from Anhui Province Key Laboratory of Optoelectronic Materials Science and Technology(No.OMST202101)the State Key Laboratory of Luminescent Materials and Devices(South China University of Technology).
文摘π-Electron coupling of pendant conjugated segment inπ-stacked semiconducting polymers always causes the formation of defect trapped sites and further quenched high-band excitons,which is harmful to the performance and stability of deep-blue polymer light-emitting diodes(PLEDs).Herein,considerate of“defect”carbazole(Cz)electromers in poly(N-vinylcarbazole)(PVK),a series of fluorene units are introduced into pendant segments(PVCz-DMeF,PVCz-FMeNPh and PVCz-DFMeNPh)to suppress the strongπ-electron coupling of pendant Cz units and enhance radiative transition toward fabricating sable PLEDs.Compared to PVCz-FMeNPh and PVCz-DFMeNPh,PVCz-DMeF spin-coated films show a relatively efficient deep-blue emission,completely similar to its single pendant chromophore,confirmed an extremely weak charge-transfer and electron coupling between adjacent pendant segments.Therefore,PLEDs based on PVCz-DMeF present stable and deep-blue emission with a high color purity(0.17,0.08),associated with extremely weak defect emission at 600∼700nm(induced by carbazole electromers).Finally,PLEDs based on PVCz-DMeF/F8BT blended films(1:1)also present the high maximum luminance(Lmax)of 6261 cd/m2 and current efficiency(CE_(max))of 2.03 cd/A,confirmed slightly trapped sites formation.Therefore,precisely control the arrangement and packing model of pendant units inπ-stacked polymer is an essential prerequisite for building efficient and stable emitter for optoelectronic devices.
基金This project was financially supported by National Natural Science Foundation of China(No.50473034).
文摘Novel fluorene-based poly(aromatic diacetylene)s have been synthesized by CuCl-catalyzed oxidative coupling of aromatic diynes.New aromatic diynes 2,7-diethynyl-9,9-bis(triphenylamine)fluorene(M_1)is synthesized by multistep reactions.The structures and properties of the polymers are characterized and evaluated by IR,NMR,TGA,UV, photoluminescence(PL),and cyclic voltammetry analyses.These polymers possess good thermal stability.All the polymers are completely soluble in coammon solvents such as toluene,THF,c...
基金supported by the State Key Basic Research Project of China (No. 2009CB623602)the National Nature Science Foundation of China (Nos. 21074038 and U0634003)
文摘Efficient white light emitting polymers were synthesized based on poly（9,9-dioctylfluorene-co-dibenzothiophene- S,S-dioxide） as blue emitter and a bisphenylamine functionalized 2,1,3-benzothiadiazole （DPABT） as red emitter. It was found that the incorporation of hole-transporting carbazole moiety into polymer main chain could effectively reduce the hole injection barriers, which can lead to distinctly improved charge balance in the emissive layer. Additionally, the hole- transporting carbazole units may form efficient bipolar host with electron-transporting dibenzothiophene-S,S-dioxide units. The white light emitting diodes based on single polymer PFSOCzDPABT showed the maximum luminous efficiency of 3.3 cd/A with the maximum luminance of 10282 cd/m2, and the luminous efficiency showed only 24% roll off at current density of 400 mA/cm2. These Commission Internationale d＇Enclairage （CIE） coordinates of the devices changed slightly with the driving voltages increasing from 8 V to 12 V, and were very close to National Television System Committee （NTSC） standard white light emission of （0.33, 0.33）. The results indicated that the incorporating bipolar host and low band gap DPABT unit was a promising way to achieve efficient single white light emitting copolymers.
基金financially supported by the National Natural Science Fund of China(Nos.20971021,51073031 and 20974018)the National Oversea Scholar Cooperation Research Found of China(No.50928301)
文摘A novel functional polyacetylene containing fluorene group as a pendant,poly（2-（p-methylstyrene）-7-acetylene-9,9-dioctyl-fluorene）, was synthesized in moderate yield by[Rh（nbd）Cl]_2-Et_3N catalyst.The structures and properties of monomer and polymer were characterized and evaluated with FTIR,NMR,UV-vis,GPC and Z-scan,respectively.The results show that the incorporation of fluorene into polyacetylene has endowed the resultant polymer with well optical limiting properties for laser at wavelength 780 nm based on two-photon absorption mechanism.
