SYNTHESIS AND CHARACTERIZATION OF NOVEL BIPOLAR PPV-BASED COPOLYMER CONTAINING TRIAZOLE AND CARBAZOLE UNITS*

Two new blue light-emitting PPV-based conjugated copolymers containing both an electron-withdrawing unit(triazole-TAZ) and electron-rich moieties (carbazole-CAR and bicarbazole-BCAR were prepared by Wittig condensationpolymerization between the triazole diphosphonium salt and the corresponding dialdehyde monomers. Their structures andproperties were characterized by FT-IR, TGA, DSC, UV-Vis, PL spectroscopy and electrochemical measurements. Theresulting copolymers are soluble in common organic solvents and thermally stable with a T_g of 147℃ for TAZ-CAR-PPVand of 157℃ for TAZ-BCAR-PPV. The maximum photoluminescence wavelengths of TAZ-CAR-PPV and TAZ-BCAR-PPV film appear at 460 nm and 480 nm, respectively. Cyclic voltammetry measurement demonstrates that TAZ-BCAR-PPVhas good electrochemical reversibility, while TAZ-CAR-PPV exhibits the irreversible redox process. The triazole unit wasfound to be an effective π-conjugation interrupter and can play the rigid spacer role in determining the emission colour ofthe resulting copolymer.     

一种含三苯胺链段的PPV类交替共聚物的合成、表征及性能

合成了三苯胺二醛和1-甲氧基-4-辛氧基-2,5-二甲苯双(三苯基氯化)两种单体,通过Wittig反应制得了共轭聚合物,对共轭聚合物进行了表征和性能测试.这类共轭聚合物的氯仿溶液和膜在紫外光激发下能发出强的蓝绿光,与小分子三苯胺衍生物(TPD)相比,具有相对较高的热稳定性和良好的成膜性.电化学分析表明聚合物具有很好的空穴传输能力.同时对共轭聚合物的光致发光和电致发光性能进行了研究,结果表明,此聚合物与同类聚对亚苯基亚乙烯基(PPV)型聚合物相比具有较低的驱动电压和较高的发光亮度,是一种潜在的有机高分子电致发光材料.     

Synthesis of polyester by means of polycondensation of diol ester and dicarboxylic acid ester through ester–ester exchange reaction

Based on our finding that the ester-ester exchange reaction between butyl benzoate and ethyl 4-phenylbenzoate in the presence of a metal alkoxide is faster than the ester-alcohol exchange reaction of butyl benzoate and ethanol, we investigated the synthesis of polyester through ester-ester exchange reaction under various conditions. The polycondensation of diol formate and methyl dicarboxylate in the presence of a catalytic amount of potassium tert-butoxide (^tBuOK) in diglyme at 120 °C under reduced pressure (90–100 Torr) afforded high-molecular-weight polyesters. Methyl dicarboxylate containing an amino group could be used for this polycondensation, although the corresponding diacid chloride containing an amino group was not isolable. The ester-ester exchange reaction could proceed even at the polyester backbone, and the reaction of poly(1,12-dodecamethylene isophthalate) ( PEs ₁ ) with poly(ε-caprolactone) (PCL) in the presence of ^tBuOK at 140 °C afforded a copolymer PEs ₁ -stat-PCL, the structure of which was confirmed by ¹³C NMR spectroscopy and DSC thermal analysis. A similar copolymer was also obtained by the polycondensation of dodecane-1,12-diol formate and dimethyl isophthalate in the presence of PCL and ^tBuOK at 120 °C under reduced pressure.     

Preparation and properties of poly(styrene-co-maleic anhydride)/silica hybrid materials by the in situ sol–gel process

Poly(styrene-co-maleic anhydride)/silica hybrid material has been successfully prepared from styrene–maleic anhydride copolymer and tetraethoxysilane (TEOS) in the presence of a coupling agent (3-aminopropyl)triethoxysilane (APTES) by an in situ sol–gel process. It was observed that the gel time of sol–gel solution was dramatically influenced by the amount of APTES. The hybrid material exhibits optical transparency almost as good as both silica gel and the copolymer. The covalent bonds between organic and inorganic phases were introduced by the aminolysis reaction of the amino group with maleic anhydride units of copolymer to form a copolymer bearing trimethoxysilyl groups, which undergo hydrolytic polycondensation with TEOS. The differential scanning calorimetry (DSC) showed that the glass transition temperature of the hybrid materials increases with increasing of SiO₂ composition. Photographs of scanning electron microscopy (SEM) and atomic force microscopy (AFM) inferred that the size of the inorganic particles in the hybrid materials was less than 20 nm. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1607–1613, 1998     

2-甲基-8-羟基喹啉-丙烯酸-镓(Ⅲ)与甲基丙烯酸甲酯共聚物的合成与表征

制备了 2 甲基 8 羟基喹啉、丙烯酸与镓 (Ⅲ )的三元配合物 ,将此配合物与甲基丙烯酸甲酯共聚后得到含镓 (Ⅲ )的共聚物 ,这种共聚物易溶于氯仿、丙酮等普通低沸点溶剂 ,具有良好的成膜性能 .用红外光谱、元素分析、紫外光谱等方法对三元配合物和共聚物的组成进行了表征 .测试三元配合物和共聚物的荧光光谱 ,表明共聚物在 4 96nm处能发出较强的荧光 .DSC和TG分析表明 ,共聚物具有良好的耐热性和热稳定性 .     

SYNTHESIS AND PROPERTIES OF ANILING ANILING AND 0-AMINOBENZENESULFONIC ACID COPOLYMER*

Poly(aniline- co-o-aminobenzenesulfonic acid) (PAOABSA) as a water soluble conducting polymerwas synthesized by chemical polymerization. The productivity and the room-temperature conductivity of thecopolymer were measured as a function of the reaction conditions, such as reaction temperature, the ratio ofoxidant to monomer and the degree of sulfonation defined as the ratio of sulfur to nitrogen atoms(S/N). Themain results obtained are summarized as follows : (1) lower reaction temperature (at about 0℃) is favorablefor the enhancement of the room-temperature conductivity of the copolymer; (2) higher content of oxidant isunfavorable for increasing the room-temperature conductivity of the copolymer; (3) both productivity androom-temperature conductivity of the copolymer decrease with increase of the degree of sulfonation whichwas always lower than 0.5 even an excess of o-aminobenzenesulfonic acid was added, probably because thereactivity ratio of aniline (γ=2.99± 0.05) is much higher than that of o-aminobenzenesulfonic acid (γ_2 = 0.06±0.02) estimated by using Fineman-Ross method and least square method.     

Synthesis and characterization of alternating fluorene–thiophene copolymers bearing ethylene glycol side-chains

Abstract  

New alternating fluorene–thiophene copolymers are introduced bearing polar ethylene glycol-carboxylate functionalities on the thiophene ring to achieve enhanced solubility in polar solvents. Suzuki polycondensation was applied to synthesize a set of three polymers with differing lengths of the ethylene glycol side-chains. The polymers are thermally stable up to temperatures of 300 °C. Solutions of the polymers in CHCl₃ show an absorption maximum at approximately 397 nm and a luminescence maximum of 472 nm in solutions with quantum yield of 30%. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels have been determined to be at −5.7 and −2.6 eV, respectively.     

TWO SPECTROSCOPICALLY AND PHOTOCHEMICALLY DISTINGUISHABLE PHYTOCHROMES IN ETIOLATED SEEDLINGS OF MONOCOTS AND DICOTS *

Abstract Fluorescence (F) emission spectra of the red-absorbing phytochrome form (Pr) at 85 K, temperature dependence of the F intensity and the extent of the Pr F changes in the phototransformation of Pr into the first stable photoproduct (lumi-R) at 85 K (γ₁,) and into the far-red-absorbing form (Pfr) at 267 K (γ₂) were investigated in etiolated shoots and roots of monocots (oat, maize, rice) and dicots (pea, cress). These characteristics monotonously changed as a function of the phytochrome content, [Ptot]: with its decrease to 3-5% of the maximal values, the F spectrum shifts from 686 nm to 682 nm, its half-band width rises from 22 nm to ca 25 nm, temperature dependence of Pr F changes its character, γ¹, drops down from ca > 0.45 to ca 0.05-0.10 and γ₂ from 0.80–0.82 to ≤0.70. These data were interpreted in terms of two different phytochromes whose relative concentration varies with [Ptot]: (1) a longer wavelength type with the F maximum at 686 nm, low activation energy of the photoreaction (Ea ≤ 3–4 kj/ mol) and high extent of the phototransformation at 85 K (0.49 ± 0.03) and at 267 K (ca 0.85) (Pra); (2) a shorter wavelength type practically inactive at 85 K with F maximum at 682 nm, higher Ea (ca 35 kj/mol) and lower extent of the Pr & Pfr phototransformation (≤0.70) (Pri). [Pra] widely varies in different parts of the seedlings (up to 100 times) and Pra dominates when [Ptot] is high. The [Pri] is much more constant (variations, <10 times), and it becomes the major one when [Ptot] drops down. The two species are likely to belong to the labile (type 1) and stable pools of pigment and not to be connected with the localization of the pigment in the cell since red-far-red preillu-mination, which is believed to bring about sequestering of the pigment, does not change their relative concentration and properties.     

SYNTHESIS AND THERMAL PROPERTIES OF A NEW CHOLIC ACIDCONTAINING COPOLYMER

A new copolymer was synthesized by free radical polymerization in solution from methyl 3α-methylacryloyl-7α, 12α-dihydroxy-5β-cholan-24-oate (MACAME) and maleic anhydride (MAN). The copolymer was characterized by FT-IR and functional group analysis. The reactivity ratios of the two monomers were estimated [r_1 = 11.6 (MACAME), r_2 = 0.01(MAN)] by conducting a series of copolymerizations with a variety of monomer feed compositions and analyzing thecopolymer composition. Thermogravimetric and differential scanning calorimetric analyses of the samples indicate that thecopolymer possesses good thermal stability. The temperature at which the copolymer samples experienced a 10% weight loss(T_(WL)) is over 287℃, and the T_g ranged from 174 to 185℃ for the copolymers.     

1,2-二乙炔基四苯基乙硅烷与1,2-二乙炔基四甲基乙硅烷的共聚及其光解

１，２－二乙炔基四苯基乙硅烷与１，２－二乙炔基四甲基乙硅烷在催化剂铑（Ⅰ）络合物［氯化三－（三苯基膦）铑］的作用下得到一种新的含硅共聚物。实验证明此共聚物的主链是有规交替结构。研究了固体薄膜及其溶液的光解作用，并测定了ＳｂＦ５蒸气处理后的共聚物薄膜的导电性。     

Synthesis and optical properties of fluorene and p-phenylenevinylene copolymers containing non-conjugated spacer

A series of alternating fluorene and p-phenylenevinylene copolymers containing non-conjugated spacer have been synthesized through the Wittig polycondensation reaction. These amorphous copolymers are highly soluble in common organic solvents and can be spin-cast to obtain transparent films. The effects of non-conjugated spacers in the main chain and the methoxyl groups on the side chain on the thermal behavior, photoluminescence (PL) and electroluminescence (EL) properties of these copolymers have been investigated in detail. Single-layered light-emitting diodes (LEDs) have been fabricated in the configuration of ITO/PEDOT/copolymer/Ca/Al and emitted blue light in the range of 456-492 nm. The measurements of current vs voltage show turn-on voltages at 6.2-12.4 V. Among the LEDs based on the six copolymers, the maximum EL brightness and efficiency of the LED based on P1 containing 4CH₂ aliphatic segment length in the main chain and without methoxyl groups on side chain are reached 3936 cd/m² and 0.70 cd/A, respectively.     

Palladium on carbon‐catalyzed direct C—H arylation polycondensation of 3,4‐ethylenedioxythiophene with various dibromoarenes

We have demonstrated a direct arylation polycondensation of 3,4‐ethylenedioxythiophene with 2,7‐dibromo‐9,9‐dioctylfluorene using palladium on carbon (Pd/C) as a catalyst. Pd/C is a low‐cost solid‐supported palladium catalyst, giving one of the effective catalytic systems for direct arylation. The Pd/C‐catalyzed direct arylation polycondensation with acetic acid/potassium carbonate in N,N‐dimethylacetamide furnished a high molecular weight π‐conjugated alternating copolymer of EDOT‐fluorene (M_n = 89,300, M_w/M_n = 3.27) in high yield. The polycondensation of EDOT with various dibromoarenes was also achieved, giving EDOT‐carbazole, EDOT‐dialylamine, and EDOT‐bithiophene polymers. Optical and electrochemical properties of the polymers were also discussed. © 2016 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 55, 1183–1188     

含氧单体和1－烯烃配位共聚合研究及共聚物表征

考察了极性含氧单体，４－戊烯氧基三甲基硅烷（ＰＴＭＳ）的络合Ⅱ型ＴｉＣｌ３Ａｌ（ｉ－Ｃ４Ｈ９）３催化体系下与丙烯共聚合情况，通过脱三甲基硅保护基，合成了丙烯，戊烯醇共聚物，并用ＩＲ，ＮＭＲ等方法进行表征，详细考察了Ａｌ／Ｔｉ比，温度等聚合条件对共聚合的影响。初步研究了共聚合的动力学行为，此外，还发现丙烯，戊烯醇共聚物保护了较好的物理性质，如较高的熔点，等规度，抗降解能力，粘接性等，为聚烯烃功能化提     

SPECTRAL CHARACTERISTICS OF FREE AND LINKED PYRENE-TYPE CHROMOPHORES IN SOLUTION,POLYMER MATRICES,AND INTERPENETRATING NETWORKS

Monomers, 1-pyrenylmethyl methacrylate (PyMMA), 1-pyrenylbutyl methacrylate (PyBMA), 4-(1-pyrenyl)methoxymethyl styrene (PyMMS) and allyl-(1-pyrenylmehtyl) ether (PyMAE), with pyrene as chromophore, were prepared. Their spectral properties (absorption, emission and emission decay) in solution, and doped or bonded in polymer matrices and complex polymer systems as interpenetrating polymer networks (IPN), were investigated. Spectral properties of pyrene-containing monomers doped in polystyrene (PS), polymethylmethacrylate (PMMA), polyvinylchloride (PVC), polyethylene (PE) and grafted on PE as well as copolymerized in buthylmethacrylate-co-styrene copolymer (BMA-co-S) have been compared. Absorption and emission spectra of pyrene type probes in solution and in IPN matrices exhibit typical absorption of the pyrene moiety. For IPN with grafted probes on PE, the absorption is slightly shifted to red wavelength. For monomers, PyMMA, PyBMA and PyMAE grafted to PE, the shape of the emission spectrum depends on the wavelength of excitation. The ratio of intensity of the vibrational band, I₁/I₃, (I₁ peak at 377 nm and I₃ peak at 388 nm) has been a quite useful indicator of polarity of IPN. The relative quantum yields of fluorescence in IPN matrices are lower in comparison to polymer matrices of PE, PS, PMMA for all probes under study. The fluorescence life-times for bound and free probes have been in the range 100–200 ns, which is substiantialy shorter than for the parent pyrene chromophore under the same or similar condition. Grafted probes on PE alone, or as a part of IPN, exhibit substantially shorter life-time around 10 ns and decay is rather complex.     

主链含苯并噻唑结构单元聚合物的合成

通过钯催化三键聚合反应,合成了主链含2,1,3-苯并噻唑的聚合物.目标化合物在普通有机溶剂,如二氯甲烷﹑氯仿﹑四氢呋喃中有较好的溶解性,目标化合物的最大吸收波长分别在424 nm和510 nm左右,光敏响应630 nm左右,其估算能隙E_g为1.96 eV,具有作为有机太阳电池材料的应用前景.     

Synthesis and characterization of biodegradable poly(L-aspartic acid-co-PEG)

The melt polycondensation reaction of the prepolymer prepared from N-(benzyloxycarbonyl)-L -aspartic acid anhydride (N-CBz-L -aspartic acid anhydride) and low molecular weight poly(ethylene glycol) (PEG) using titanium isopropoxide (TIP) as a catalyst produced the new biodegradable poly(L -aspartic acid-co-PEG). This new copolymer had pendant amine functional groups along the polymer backbone chain. The optimal reaction conditions for the preparation of the prepolymer were obtained by using a 0.12 mol % of p-toluenesulfonic acid with PEG 200 for 48 h. The weight-average molecular weight of the prepolymer increased from 1,290 to 31,700 upon melt polycondensation for 6 h at 130°C under vacuum using 0.5 wt % TIP as a catalyst. The synthesized monomer, prepolymer, and copolymer were characterized by FTIR, ¹H- and ¹³C-NMR, and UV spectrophotometers. Thermal properties of the prepolymer and the protected copolymer were measured by DSC. The glass transition temperature (T_g) of the prepolymer shifted to a significantly higher temperature with increasing molecular weight via melt polycondensation reaction, and no melting temperature was observed. The in vitro hydrolytic degradation of these poly(L -aspartic acid-co-PEG) was measured in terms of molecular weight loss at different times and pHs at 37°C. This pH-dependent molecular weight loss was due to a simple hydrolysis of the backbone ester linkages and was characterized by more rapid rates of hydrolysis at an alkaline pH. These new biodegradable poly(L -aspartic acid-co-PEG)s may have potential applications in the biomedical field. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2949–2959, 1998     

FREE RADICAL COPOLYMERIZATION AND KINETIC TREATMENT OF CYCLOHEXENE WITH N-PHENYLMALEIMIDE

The copolymerization of cyclohexene (M₁) and N-phenylmaleimide (M₂) in chloroform with 2,2'-azo-bis(isobutyronitrile) as an initiator was investigated. The copolymerization of N-phenylmaleimide with cyclohexene in chloroform proceeded in a homogeneous system to give an alternating copolymer over a wide range of the comonomer composition in the feed. The kinetic parameters, such as reactivity ratio, overall activity energy and the effect of comonomer composition on the initial copolymerization rate (R_p) were determined. The bimolecular termination of the copolymerization was proved. A kinetic treatment based on the model of mechanism was proposed and used to test the copolymerization of cyclohexene and N-phenylmaleimide and to quantitatively estimate the k₂₁/k₁₂ value.     

SYNTHESIS AND CHARACTERIZATION OF POLY(ASPARTIC ACID) AND ITS DERIVATIVES AS BIODEGRADABLE MATERIALS

ABSTRACT

Three types of modified poly(aspartic acid)s, such as poly(aspartic acid-co-aminocarboxylic acid) (4), alkylamine modified poly(aspartic acid) (5) and crosslinked poly(aspartic acid) (6), were synthesized and calcium-ion chelating ability, hygroscopicity and water absorption were evaluated. The calcium-ion chelating ability of 4 depended on the kind of aminocarboxylic acids and the content of aminocarboxylic acid in the copolymer. The highest value was 3 times higher than that of poly(acrylic acid) with a M_w of 14000. The highly modified PASP, e.g., 50 mol% lauryl amine modified poly(aspartic acid), showed the highest by grogroscopicity among homopoly(aspartic acid)s and modified poly(aspartic acid)s. The maximum swelling of poly(aspartic acid) hydrogel prepared by the γ-irradiation of homopoly(as-partic acid) was 3400 g-deionized water/g-dry hydrogel.     

New block copolymers V. Synthesis,characterization and morphological studies of poly(pentamethylene terephthalate)-b-(acrylonitrile butadiene rubber)

A block copolymer was prepared by low temperature polycondensation between (acid chloride)-terminated poly(pentamethylene terephthalate) as the hard block, and amine-terminated acrylonitrile-butadiene rubber, as the soft block. The polymer was characterized by nitrogen analysis, IR and NMR spectroscopy. The polymer showed two glass transition temperatures (T _g ) and exhibited two-phase morphology.     

Synthesis,Electrochemical, and Optical Properties of a Novel PPV/PPE Block‐Copolymer

Summary: A novel poly(p‐phenylene vinylene) (PPV)/poly(p‐phenylene ethynylene) (PPE) block‐copolymer was synthesized by a cross‐coupling polycondensation with Pd(PPh₃)₂Cl₂ and a phase‐transfer catalyst, and was confirmed by ¹H NMR and IR spectroscopy and elemental analysis. The thermal, electrochemical, and photoluminescent properties of the new copolymer have been investigated. The incorporation of triple bonds into the cyano‐substituted PPV (CN‐PPV) backbone leads to higher oxidation and reduction potentials than poly(2‐methoxy‐5‐(2‐ethylhexyloxy)‐p‐phenylene vinylene) (MEH‐PPV) and CN‐PPV, potentially making the copolymer a good electron‐transporting material for use in a light‐emitting‐diode device.

The cyclic voltammogram of the novel poly(p‐phenylene vinylene) (PPV)/poly(p‐phenylene ethynylene) (PPE) block‐copolymer synthesized here.