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1.
A series of functional polyacetylenes (PAs) bearing diphenyl oxadiazole pendant groups ( P1 – P4 ) were prepared, and the resultant polymers are completely soluble in common organic solvents. Their structures and properties were characterized and evaluated by DSC, TGA, UV, PL, CV, and EL analyses. The results show that all the resulting polymers possesses low LUMO energy level and high thermal stability, and the resultant functional polyacetylenes without spacer group between the polyacetylene conjugated main chain and oxadiazole pendant groups ( P1 – P3 ) show lower LUMO energy level (~?3.87 eV) and higher thermal properties (Tg) than that ( P4 ) with a flexible spacer. The resultant polymer ( P2 ) was applied as an ETM in bilayer electroluminescent devices and effectively enhances external quantum efficiency and the brightness of device, and decreases turn‐on voltages of devices. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1406–1414, 2010  相似文献   

2.
A novel aromatic diacid, 3, 5‐dicarboxyl‐4′‐amino diphenyl ether, containing pendant phenoxy amine group was synthesized. Homo‐ and co‐polybenzimidazoles containing different content of pendant phenoxyamine groups were synthesized by condensation of 3,3′‐diaminobenzidine with this acid and a mixture of this acid and isophthalic acid in different ratio in polyphosphoric acid. Copolybenzimidazoles with structural variations were also synthesized based on this acid and pyridine dicarboxylic acid, terephthalic acid, adipic acid, or sebacic acid. The polymers have good solubility in polar aprotic solvents and strong acids and they form tough flexible films by solution casting. The polymers were characterized by different instrumental techniques (FTIR, TGA, DSC, XRD, etc.) and for solvent solubility, mechanical properties, inherent viscosity, and proton conductivity. The inherent viscosities of the polymers vary in the range of 0.62–1.52 dL/g. They have high thermal stability up to 475–506 °C (IDT) in nitrogen, high glass transition temperatures (Tg) ranging from 313 to 435 °C and good tensile strength ranging from 58 to 125 MPa. Proton conductivity of homo polymer is 3.72 × 10?3 S/cm at 25 °C and 2.45 × 10?2 S/cm at 200 °C © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 5776–5793, 2008  相似文献   

3.
Two new luminescent copolyethers ( P1 and P2 ) with isolated 2,5‐distyrylthiophene‐emitting segments and electron‐transporting 2,5‐diphenyl‐1,3,4‐oxadiazole chromophores were successfully synthesized by the Horner–Wadworth–Emmons reaction. The solubility, optical, and electrochemical properties of the polymers were investigated and correlated with nonlinear thiophene and 1,3,4‐oxadiazole groups. P2 with pendant 1,3,4‐oxadiazole was soluble in common organic solvents such as chloroform, tetrahydrofuran, and C2H2Cl4. Thermogravimetric analysis and differential scanning calorimetry showed that the copolyethers were thermally stable below 345 °C, with glass‐transition temperatures higher than 110 °C. They were yellow‐greenish emitting materials with a band gap of 2.57–2.58 eV estimated from the onset absorption. Incorporating the thiophene moiety narrowed the band gaps of the copolyethers. The photophysical and electronic properties of the polymer and the preliminary electroluminescent device made from the polymer demonstrate that the polymer may be a potential candidate material for the fabrication of polymeric light‐emitting devices. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 2927–2936, 2002  相似文献   

4.
Series of poly(p‐phenylene)s (PPPs) containing terphenyl mesogenic pendants with cyano and methoxy terminal groups by flexible ? COO(CH2)6O? bridge [ P(CN) and P(OCH3) ] are synthesized through Yamamoto polycondensation with Ni‐based complex catalysts. The effects of the structural variation on their properties, especially their mesomorphism, ultraviolet–visible (UV), and photoluminescence behaviors, are studied. All of the polymers are stable, losing little of their weights when heated to ≥340 °C. The polymers show good solubility and can be dissolved in common solvents. P(CN) with cyano terminal group shows enantiotropic SmAd phase with bilayer packing arrangement, while P(OCH3) with methoxy terminal group readily forms nematic and SmAd phase when heated and cooled. Photoexcitation of their solutions induces strong blue light emission. Compared with P(OCH3) , the light‐emitting bands of polymer P(CN) is slightly redshifted to 428 nm and the emission intensity of P(CN) is much stronger, due to the existence of donor–acceptor pairs. More interestingly, both of the polymers exhibit obvious Cotton effect on the CD spectra, resulting from the predominant screw sense of the backbone. This indicates that the bulky mesogenic pendant orientating around the backbone will force the main chain with helical conformation in the long region due to steric crowdedness. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4723–4735, 2009  相似文献   

5.
Three new types of hyperbranched photoactive liquid crystalline siloxane polymers containing azo moieties were synthesized using click chemistry methodology. The polymers were soluble in most of the polar solvents like chloroform, tetrahydrofuran, dimethylformamide, dimethyl sulphoxide and dichloromethane. The molecular weights of the polymers were in the range of 9000–12,000 g mol?1. The trans‐cis photoisomerization of the polymer were studied both under UV radiation and dark. The isomerization rate constants were found to be in the range of 0.7–1.4 × 10?2 sec?1 and 7.0 × ?2.5 × 10?5 sec?1. The thermotropic behavior of the polymers was studied by using polarizing optical microscopy and differential scanning calorimetry, respectively. The polymers P1 and P2 showed liquid crystalline texture characteristic of nematic phase. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

6.
Hyperbranched organic–inorganic hybrid conjugated polymers P1 and P2 were prepared via FeCl3‐oxiditive polymerization of 4,7‐bis(3‐ethylhexyl‐2‐thienyl)‐2,1,3‐benzothiadiazole ( A ) and octa(3‐ethylhexyl‐2‐thienyl‐phenyl)polyhedral oligomeric silsesquioxane (POSS) ( B ) at different POSS concentrations. Compared to linear polymer PM derived from A , P1 , and P2 exhibit much higher PL quantum efficiency (?PL‐f) in condensed state with improved thermal stability. ?PL‐f of P1 and P2 increased by 80% and 400%, and the thermal degradation temperatures of P1 and P2 are increased by 35 °C and 46 °C, respectively. Light‐emitting diodes were fabricated using P1 , P2 , and PM . While the electroluminescent spectra of both P1 and PM show λmax at 660 nm, P1 exhibits a much narrower EL spectrum and higher electroluminescence (~500%) compared with PM at a same voltage and film thickness. The maximum current efficiency of P1 is more than seven times of that of PM . The turn‐on voltages of the LEDs are in the order of P2 > PM > P1 . LED prepared by blending P1 with MEH‐PPV shows a maximum luminescence of 2.6 × 103 cd/m2 and a current efficiency of 1.40 cd/A, which are more than twice (1.1 × 103 cd/m2) and five times (0.27 cd/A) of LED of PM /MEH‐PPV blend, respectively. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5661–5670, 2009  相似文献   

7.
The synthesis, one‐ and two‐photon absorption (TPA) and emission properties of two novel 2,6‐anthracenevinylene‐based copolymers, poly[9,10‐bis(3,4‐bis(2‐ethylhexyloxy)phenyl)‐2,6‐anthracenevinylene‐alt‐N‐octyl‐3,6‐carbazolevinyl‐ene] ( P1 ) and poly[9,10‐bis(3,4‐bis(2‐ethylhexyloxy)phenyl)‐2,6‐anthracenevinyl‐ene‐alt‐N‐octyl‐2,7‐carbazolevinylene] ( P2 ) were reported. The as‐synthesized polymers have the number‐average molecular weights of 1.56 × 104 for P1 and 1.85 × 104 g mol?1 for P2 and are readily soluble in common organic solvents. They emit strong bluish‐green one‐ and two‐photon excitation fluorescence in dilute toluene solution (? P1 = 0.85, ? P2 = 0.78, λem( P1 ) = 491 nm, λem( P2 ) = 483 nm). The maximal TPA cross‐sections of P1 and P2 measured by the two‐photon‐induced fluorescence method using femtosecond laser pulses in toluene are 840 and 490 GM per repeating unit, respectively, which are obviously larger than that (210 GM) of poly[9,10‐bis‐(3,4‐bis(2‐ethylhexyloxy) phenyl)‐2,6‐anthracenevinylene], indicating that the poly(2,6‐anthracenevinylene) derivatives with large TPA cross‐sections can be obtained by inserting electron‐donating moieties into the polymer backbone. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 463–470, 2010  相似文献   

8.
Poly((2‐Alkylbenzo[1,2,3]triazole‐4,7‐diyl)vinylene)s (pBTzVs) synthesized by Stille coupling show different absorption spectra, solid‐state morphology, and photovoltaic performance, depending on straight‐chain versus branched‐chain (pBTzV12 and pBTzV20) pendant substitution. Periodic boundary condition density functional computations show limited alkyl pendant effects on isolated chain electronic properties; however, pendants could influence polymer backbone conjugative planarity and polymer solid film packing. The polymers are electronically ambipolar, with best performance by pBTzV12 with hole and electron transport mobilities of 4.86 × 10?6 and 1.96 × 10?6 cm2 V?1 s?1, respectively. pBTzV12 gives a smooth film morphology, whereas pBTzV20 gives a very different fibrillar morphology. For ITO/PEDOT:PSS/(1:1 w/w polymer:PC71BM)/LiF/Al devices, pBTzV12 gives power conversion efficiency (PCE) up to 2.87%, and pBTzV20 gives up to PCE = 1.40%; both have open‐circuit voltages of VOC = 0.6–0.7 V. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2015 , 53, 1539–1545  相似文献   

9.
A series of novel branched polythiophene derivatives bearing different densities of vinylene‐bridges as linking chains were synthesized by a general synthetic strategy. The organic field‐effect transistors, which were fabricated by spin‐coating the polymer solutions onto octadecyltrichlorosilane‐modified SiO2/Si substrates with top‐contact configuration, afforded a high mobility of 8.0 × 10?3 cm2 V?1 s?1 with an on/off ratio greater than 104 and a threshold voltage of about ?3 V in saturation regime. The devices based on these polymers possessed better performance than those of polymers without conjugated bridges and polymers with longer conjugated bridges. These results demonstrated that the combination of conjugated polythiophene backbones and vinylene‐bridges would improve the carrier mobility. As an emerging class of conjugated materials, polymers with vinylene‐bridges as linking chains would open up new opportunities in organic electronics, and their applications in organic electronics are promising. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1381–1392, 2009  相似文献   

10.
Hyperbranched poly(ether nitrile)s were prepared from a novel AB2 type monomer, 2‐chloro‐4‐(3,5‐dihydroxyphenoxy)benzonitrile, via nucleophilic aromatic substitution. Soluble and low‐viscous hyperbranched polymers with molecular weights upto 233,600 (Mw) were isolated. According to the 1H NMR and GPC data, the unique polymerization behavior was observed, which implies that the weight average molecular weight increased after the number average molecular weight reached plateau region. Model compounds were prepared to characterize the branching structure. Spectroscopic measurements of the model compounds and the resulting polymers, such as 1H, DEPT 13C NMR, and MS, strongly suggest that the ether exchange reaction and cyclization are involved in the propagation reaction. The side reactions would affect the unique polymerization behavior. The resulting polymers showed a good solubility in organic solvents similar to other hyperbranched aromatic polymers. The hydroxy‐terminated polymer was even soluble in basic water. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 5835–5844, 2009  相似文献   

11.
Two PPV‐based bipolar polymers containing 1,3,4‐oxadiazole pendant groups were synthesized via the Gilch polymerization reaction for use in light‐emitting diodes (LEDs). The resulting polymers were characterized using 1H and 13C NMR, elemental analysis, DSC, and TGA. These polymers were found to be soluble in common organic solvents and are easily spin‐coated onto glass substrates, producing high optical quality thin films without defects. The electro‐optical properties of ITO/PEDOT/polymer/Al devices based on these polymers were investigated using UV‐visible, PL, and EL spectroscopy. The turn‐on voltages of the OC1Oxa‐PPV and OC10Oxa‐PPV devices were found to be 8.0 V. The maximum brightness and luminescence efficiency of the OC1Oxa‐PPV device were found to be 544 cd/m2 at 19 V and 0.15 cd/A, respectively. © 2007 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 1098–1110, 2008  相似文献   

12.
The polymers with functionalized alkoxy groups and with narrow molecular weight distribution (Mw/Mn < 1.12) are obtained from the living polymerization of 2‐alkoxy‐1‐methylenecyclopropanes using π‐allylpalladium complex, [(PhC3H4)Pd(μ‐Cl)]2, as the initiator. The polymers with oligoethylene glycol groups in the alkoxy substituent are soluble in water, and hydroboration of the C?C double bond and ensuing addition of the OH groups to C?N bond of alkyl isocyanate produce the polymers with urethane pendant groups. The reaction decreases solubility of the polymer in water significantly. Di‐ and triblock copolymers of the 2‐alkoxy‐1‐methylenecyclopropanes are prepared by consecutive addition of the two or three 2‐alkoxy‐1‐methylenecyclopropane monomers to the Pd initiator. The polymers which contain both hydrophobic butoxy or tert‐butoxy group and hydrophilic oligoethylene glycol group dissolve in water and/or organic solvents, depending on the substituents. The 1H NMR spectrum of poly( 1a ‐b‐ 1h ) (? (CH2C(?CH2)CHOBu)n? (CH2C(?CH2)CH(OCH2CH2)3OMe)m? ) in D2O solution exhibits peaks because of the butoxy and ?CH2 hydrogen in decreased intensity, indicating that the polymer forms micelle particles containing the hydrophilic segments in their external parts. Aqueous solution of the polymer with a small amount of DPH (DPH = 1,6‐diphenyl‐1,3,5‐hexatriene) shows the absorbance due to DPH at concentration of the polymer higher than 5.82 × 10?5 g mL?1. Other block copolymers such as poly( 1b ‐b‐ 1h ) and poly( 1a ‐b‐ 1g ) also form the micelles that contain DPH in their core. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 959–972, 2009  相似文献   

13.
Synthesis of two conducting polymers containing 3‐hexylthiophene and 3‐[2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy]thiophene is demonstrated. In thin‐film transistors, the high‐molecular‐weight polymer shows an average mobility of 4.2 × 10?4 cm2 V?1 s?1. Most importantly, the polymers have high conductivity upon doping with iodine and also have high stability in the doped state with high conductivities measured even after 1 month. Furthermore, the doping causes transparency to thin films of the polymer and the films are resistant to common organic solvents. All these properties indicate a great potential for the iodine‐doped polymer to be used as an alternative to commercially available poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate). © 2019 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2019 , 57, 1079–1086  相似文献   

14.
Two new orange red light‐emitting hyperbranched and linear polymers, poly(pyridine phenylene)s P1 and P2, were prepared by the Heck coupling reaction. In particular, an A2 + B3 approach was developed to synthesize conjugated hyperbranched polymer P2 via one‐pot polycondensation. The polymers were characterized by NMR, Fourier transform infrared, ultraviolet–visible, and elemental analysis. They showed excellent solubility in common solvents such as tetrahydrofuran, CH2Cl2, CHCl3, and N,N‐dimethylformamide and had high molecular weights (up to 6.1 × 105 and 5.8 × 105). Cyclic voltammetry studies revealed that P2 had a low‐lying lowest unoccupied molecular orbital energy level of ?3.22 eV and a highest occupied molecular orbital energy level of ?5.43 eV. The thin film of P2 emitted strong orange‐red photoluminescence at 595 nm. A double‐layer light‐emitting diode fabricated with the configuration of indium tin oxide/P2/tris(8‐hydroxy‐quinoline)aluminum/Al emitted orange‐red light at 599 nm, with a brightness of 662 cd/m2 at 7 V and a turn‐on voltage of 4.0 V; its external quantum efficiency was calculated to be 0.19% at 130.61 mA/cm2. This indicated that this new electroluminescent polymer (P2) based on 3,5‐dicyano‐2,4,6‐tristyrylpyridine could possibly be used as an orange‐red emitter in polymer light‐emitting displays. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 493–504, 2005  相似文献   

15.
A series of new phenothiazine‐based donor–acceptor copolymers, P1 and P2, were synthesized via a Suzuki coupling reaction. The weight‐averaged molecular weights (Mw) of P1 and P2 were found to be 16,700 and 16,100, with polydispersity indices of 1.74 and 1.39, respectively. The UV–visible absorption spectra of the polymer thin films contained three strong absorption bands in the ranges 318–320 nm, 430–436 nm, and 527–568 nm. The absorption peaks at 320 and 430 nm originated mainly from the phenothiazine‐based monomer units, and the longer wavelength absorption band at 527–568 nm was attributed to the increased effective conjugation length of the polymer backbones. Solution‐processed field‐effect transistors fabricated with these polymers exhibited p‐type organic thin film transistor characteristics. The field‐effect mobilities of P1 and P2 were measured to be 1.0 × 10?4 and 7.5 × 10?5 cm2 V?1 s?1, respectively, with on/off ratios in the order of 104 for all polymers. A photovoltaic device in which a P2/PC71BM (1/3) blend film was used as the active layer exhibited an open‐circuit voltage (VOC) of 0.70 V, a short‐circuit current (JSC) of 6.79 mA cm(2, a fill factor of 0.39, and a power conversion efficiency of 1.86% under AM 1.5 G (100 mW cm?2) illumination. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012  相似文献   

16.
Pure exo‐functional norbornene monomers containing various chromophores such as fluorene, pyrene, and carbazole were successfully prepared via the Diels–Alder reaction and condensation reaction. The living ring‐opening metathesis polymerization (ROMP) of a fluorene‐containing monomer, exo‐2‐(fluorene‐9‐ylcarboxymethyl)norborn‐5‐ene (exo‐1), was observed and confirmed by the formation of a diblock copolymer and a linear relationship between the number‐average molecular weight and [M]/[I] ratios ([M] = monomer concentration; [I] = initiator concentration). The synthesis and characteristics of novel fluorene‐containing polymers based on pure exo‐1 are reported with Grubbs catalyst I {RuCl2(CHPh)[P(C6H11)3]2} with a high molecular weight of 3.18 × 104 in 90 s ([M]/[I] = 100). However, the ROMP of pyrene‐ and carbazole‐containing monomers [exo‐5‐(pyrene methoxy carbonyl)bicyclo[2.2.1]hept‐2‐ene and exo‐5‐(carbazole ethoxy carbonyl)bicyclo[2.2.1]hept‐2‐ene, respectively] were carried out in a nonliving fashion. All the chromophore‐containing polymers showed excellent solubility in various organic solvents, particularly in chloroform, N‐methyl‐2‐pyrrolidinone, and 1,2‐dichlorobenzene. The glass transition temperatures of polynorbornenes containing various chromophores were determined to be 80–109 °C (by differential scanning calorimetry) higher than that of ring‐opened polynorbornene (glass transition temperature = 35 °C), indicating that the incorporation of the pendant aromatic moieties (e.g., fluorene, pyrene, and carbazole) could enhance the transition temperature for segmental motions of polymer chains. The photoluminescence spectra of all polymer solutions showed a strong emission in the blue region of the visible spectra. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 3022–3031, 2007  相似文献   

17.
A novel synthetic strategy was developed to prepare polyphosphazenes containing C60 moieties as side chains. Thus, a new reactive macromolecular intermediate, polyphosphazene azides ( P1 ), was obtained from poly(dichlorophosphazene) by the direct nucleophilic substitution reaction. Then the azide group in P1 reacted with C60 molecules to afford the first example of C60‐containing polyphosphazenes ( P2 and P3 ). The polymers are soluble in common organic solvents. Molecular structural characterization for the polymers was presented by 1H NMR, 13C NMR, IR, ultraviolet–visible spectra, and gel permeation chromatography. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 194–199, 2004  相似文献   

18.
Cyclopolymerization of 1,6‐heptadiyne derivatives containing the bulky substitutents was carried out by metathesis catalyst systems. The catalytic activity of molybdenum (V) chloride (MoCl5) in homopolymerization is greater than that of the MoCl5‐cocatalyst system, and copolymerization is vice versa in catalytic activity. Newly synthesized homo‐ and copolymers were soluble in common organic solvents and could afford thin film by solution‐casting onto the indium–tin oxide coated glass substrate. The NMR, Fourier transform infrared spectroscopic, and UV–visible spectra indicated that these polymers have a linear conjugated cyclic polyene structure having a bulky substitutent as a pendant group. The number‐average molecular weight of these polymers was in the range of 2.4–6.27 × 103. The copolymers exhibited a relatively higher molecular weight than that of the homopolymers. The copolymers were stable up to 380 °C. The electrical conductivities of the I2‐doped copolymer thin film by the four‐point probe method and surface plasmon resonance spectroscopy were about 500 and 600 S/cm, respectively. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 958–964, 2002  相似文献   

19.
1‐{3,4‐Di‐(2‐hydroxyethoxy)phenyl}‐2‐(2‐thiophenyl)ethene (5) was prepared and condensed with terephthaloyl chloride to yield polyester (6). Polymer 6 was reacted with tetracyanoethylene to give a new Y‐type polyester (7) containing 1‐(3,4‐dioxyethoxy)phenyl‐2‐{5‐(2,2,3‐tricyanovinyl)‐2‐thiophenyl)}ethenyl groups as NLO‐chromophores, which are components of the polymer backbones. Polyester 7 is soluble in common organic solvents such as N,N‐dimethylformamide and acetone. Polymer 7 showed a thermal stability up to 300 °C in thermogravimetric analysis with glass transition temperature (Tg) obtained from differential scanning calorimetry near 126 °C. The second harmonic generation (SHG) coefficient (d33) of poled polymer film at the 1560 nm fundamental wavelength was around 6.57 × 10?9 esu. The dipole alignment exhibited high thermal stability up to the Tg, and there was no SHG decay below 125 °C due to the partial main‐chain character of polymer structure, which is acceptable for NLO device applications. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 1911–1919, 2009  相似文献   

20.
Phosphonate‐functionalized polysiloxanes have been prepared with a new siloxane/phosphonate monomer. The reaction of 3‐chloropropylmethyldimethoxysilane with trimethylphosphite or triethylphosphite produces several new monomers containing pendant phosphonate groups. Copolymerization with dimethyldimethoxysilane has produced polymers soluble in most organic solvents. The acid hydrolysis of the phosphoryl esters has produced hydrophilic siloxane polymers containing phosphonic acid groups. The thermal properties of the polymers and several related small molecules have been compared with thermogravimetric analysis. Both the monomers and the resulting polymers have been characterized with 1H, 13C, 31P, and 29Si NMR. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 48–59, 2003  相似文献   

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