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Three types of fullerene (C60)-end-capped poly(4-diphenylaminostyrene) (C60–PDAS) and poly(4-diphenylaminostyrene) (PDAS) blends were prepared to investigate their potential as bipolar polymer semiconductors. The concentration of C60 in the C60–PDAS/PDAS blends strongly affected the hole and electron drift mobility values; the hole drift mobility decreased with an increase in the C60 concentration. However, the electron drift mobility increased with an increase in the C60 concentration. The hole and electron drift mobility values were almost the same for the 1/2 C60–PDAS/PDAS blend; therefore, this polymer blend was thought to be a bipolar polymer semiconductor. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011

Block copolymerization of plural types of monomers offers a new opportunity for the preparation of a variety of multifunctional polymers. Poly(4-diphenylaminostyrene) (PDAS)-poly(9-vinylanthracene) (PVAN) binary block copolymer (PDAS-PVAN) was synthesized by (living) anionic polymerization using the benzyllithium/N,N,N′,N′-tetramethylethylenediamine system. The photoluminescence emission of PDAS-PVAN was enhanced by the fluorescence resonance energy transfer from PDAS block to PVAN block in PDAS-PVAN. The hole drift mobility of the copolymer was controllable by the amount of triphenylamino groups in the polymer chain. The optical and electrical properties of PDAS-PVAN were adjustable through the polymer chain structure. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

The effect of polymer chain structure on the optical and electrical properties are reported for poly(4-diphenylaminostyrene) (PDAS), which was prepared by the living anionic polymerization of 4-diphenylaminostyrene (DAS) with the benzyllithium (BzLi)/ N , N , N ′, N ′-tetramethylethylenediamine (TMEDA) system. The optical properties of PDAS are strongly affected by the stereoregularity of the PDAS polymer chain; intramolecular excimer-forming fluorescence was observed from PDAS with a syndiotactic-rich configuration. The highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels of PDAS were approximately −5.4 and −2.0 eV, respectively, regardless of the polymer chain structure. The hole and electron drift mobilities for PDAS were in the order of 10 −4 to 10 −5 (cm 2 /V s) and 10 −5 (cm 2 /V s), respectively, with negative slopes. The distance of each triphenylamino (TPA) group in the polymer chain was a major factor influencing the drift mobility of PDAS. The current–voltage ( I – V ) characteristics of PDAS were controllable according to the polymer chain structure of PDAS.

Structure analyses for hydrate models of ethyleneimine oligomer (5-mer as model of PEI) were investigated by quantum chemical calculations. Conformation energies and structures optimized for hydrate models of (ttt)5 and (tgt)5 conformers were examined. Hydrate ratio, h [h = H2O/N (mol)], was set from 0.5 to 2. In anhydrates, (tg+t)5 conformer was more stable (?1.8 kcal/m.u.) than (ttt)5. In hydrates, (ttt)5 conformers were more stable (?0.7 - ?4.3) than (tg+t)5. These results corresponded to experimental results that anhydrous linear PEI crystal changes from double helical to single planar chain in hydration process. Structures calculated for (ttt)5 agreed in those observed for hydrates of PEI. In all (tg+t)5 conformers, O???H bonds between waters were found with the decreases of N???H bonds between imino group and water. The O???H bonds in (tg+t)5 conformer resulted in its high chain torsion, and strongly related with instability and structure change (large swelling).

Hole transport copolymers consisting of 3,4-ethylenedioxythiophene (EDOT) and N-4-butylphenyl-N,Ndiphenylamine (BTPA) were synthesized by oxidative coupling reaction using FeCl3 as an oxidant. These copolymers showed good solubility and their thin films showed sufficient morphological stability. The copolymers showed an absorption maximum around 320 nm. Copolymers had an oxidation peak at approximately 1.03∼1.14 V versus the Ag/AgCl electrode. The hole mobility increased with increasing portion of the EDOT unit. The hole mobility of the copolymer containing 57% of the EDOT unit showed the highest mobility of 3×10-5 cm2/V·s.

The grafting reaction of poly( N -vinylcarbazolyl)lithium (PNVCLi) with tert -butyllithium onto fullerene-C 60 (C 60 ) was examined to explore the possibility of preparing new materials for effective photovoltaic cells. When the molar ratio of C 60 /Li was over four, the grafting reaction products obtained were completely soluble in tetrahydrofuran. The number-average molecular weight of the grafting reaction products obtained was greater than that of the respective parent PNVCs, indicating the formation of PNVC with a C 60 end-group. Gel permeation chromatography and 13 C NMR analyses showed that the product of the grafting reaction was C 60 bonded to PNVC and t -butyl groups. UV/vis and PL spectra suggested that this PNVC may be useful for preparing effective photovoltaic cells.

Soluble poly(para-phenylene) having a long polymer chain (more than six repeat units) was synthesized with a tert-butyl end-group (t-PPP) and was found to have improved solubility and excellent optical properties. Poly(1,3-cyclohexadiene) (PCHD) consisting of only 1,4-cyclohexadiene (1,4-CHD) units was synthesized with a tert-butyl end-group (t-PCHD), and completely dehydrogenated to obtain t-PPP. This end-group effectively prevented the crystallization of t-PPP, and polymers containing up to 16 repeat units were soluble in tetrahydrofuran. Soluble t-PPP obtained had an ability to form a tough thin film prepared by spin-coating method. Optical analyses of t-PPP provided strong evidence for a linear polymer chain structure. A block copolymer of t-PPP and a soluble polyphenylene (PPH) was then synthesized, and the excellent optical properties were retained by this block copolymer along with its solubility.

N-butyl-N,N-diphenylamine (BDPA) and N-4-butylphenyl-N,N-diphenylamine (BTPA) were polymerized by oxidation polymerization using iron (III) chloride as oxidant. BDPA showed higher polymerizability. Poly(BDPA) and poly(BTPA) showed UV absorption maximum at 362 and 373 nm. Oxidation potential of poly(BDPA) was 1.02 V versus Ag/AgCl, while that of poly(BTPA) was 1.12 V. Hole mobility of poly(BDPA) was 4.93 × 10−5 cm2/Vs and that of poly(BTPA) was 2.89 × 10−5 cm2/Vs at the electric field of 35 V/μm. The differences of the properties were explained by the higher electron donating power of alkyl group than phenyl group and conjugation of phenyl ring. It was found that both poly(BDPA) and poly(BTPA) can be used as hole transporting material for electroluminescent device.

A well-controlled anionic polymerization of 4-diphenylaminostyrene (DAS) with alkyllithium (RLi) has been achieved for the first time. The nucleophilicity and solubility of RLi, 4-diphenylaminostyryllithium (DASLi), and poly(4-diphenylaminostyryl)lithium (PDASLi) were very important controlling factors. An initiator system of tert-butyllithium (t-BuLi)/N,N,N′,N′-tetramethylethylenediamine (TMEDA) in toluene was found to be very effective. In this system, the t-BuLi/TMEDA complex reacts with toluene to form the benzyllithium (BzLi)/TMEDA complex, and this complex initiates the anionic polymerization of DAS. The DASLi/TMEDA and PDASLi/TMEDA complexes have sufficient nucleophilicity and stability as propagating species, without the metalation of toluene, and as a result, living anionic polymerization was achieved. The high molecular weight poly(4-diphenylaminostyrene) (PDAS), synthesized using the RLi/TMEDA system, had a syndiotactic-rich configuration, independent of the polymerization solvent.

Photoconductive poly(4-butyltriphenylamine) particles were prepared by a chemical oxidative dispersion polymerization. The utilization of statistical copolymer of methyl methacrylate with 2-hydroxyethyl methacrylate (30:70) as a dispersant afforded particles with the narrowest distribution when the other experimental conditions such as the rate of monomer feed, and the dispersant concentration were appropriately selected. Porous particles were obtained at 40 °C using poly(vinyl pyrrolidone) as a dispersant.

Hole transport polymers consisting of 4-methoxytriphenylamine (P-MOTPA) and 4- n -butyltriphenylamine (P-BTPA) were synthesized by oxidative coupling reaction using FeCl 3 as an oxidant. These polymers had good solubility and their thin films showed sufficient morphological stability. 1 H NMR and 13 C NMR revealed that the monomers were exclusively connected at the p -positions of unsubstituted phenyl groups. Polymers had UV absorption maximum around 370 nm. Cyclic voltammograms of polymers showed well-defined pairs of reduction and oxidation peaks at 1.1 V versus Ag/AgCl, indicating that the polymers are electrochemically active. P-MOTPA and P-BTPA had hole drift mobility of being 4.04 × 10 −5 and 2.98 × 10 −5 cm 2 /V s at the electric field of 50 V/μm, respectively.

Polystyrene (PSt)/poly (4-butyltriphenylamine; PBTPA) composite particles was prepared by a chemical oxidative seeded dispersion polymerization of (4-butyltriphenylamine) with PSt seed particles that were prepared by nonaqueous dispersion polymerization of styrene. Monodisperse composite particles were obtained when the ratio of monomer to seed, the rate of monomer feed, and poly(N-vinyl pyrrolidone; PVP) concentration was appropriately selected. The introduction of PBTPA was confirmed by the presence of the characteristic absorption band attributed to PBTPA from a Fourier transform infrared spectra. The solvent extraction with ethyl acetate revealed that composite particles consisted of PSt core and PBTPA shell. Then two-dimensional arrays of composite particles were also fabricated.

BACKGROUND: Poly(1,3-cyclohexadiene) (PCHD) is of interest as a precursor for the synthesis of a new class of high-performance hydrocarbon polymers. ω-Functionalization of PCHD offers a new opportunity for the preparation of a variety of multifunctional PCHD derivatives. RESULTS: ω-Functionalized PCHD containing a fluorenyl (or anthracenyl) group at the polymer chain end was successfully synthesized by post-polymerization reaction of poly(1,3-cyclohexadienyl)lithium (PCHDLi) with alkyl halides containing a fluorescent functional group. The degree of nucleophilicity of PCHDLi and the control of side reactions were very important factors to achieve a high conversion for the post-polymerization reactions of PCHDLi. The ω-functionalized PCHDs obtained exhibited strong photoluminescence and the wavelength of the fluorescence was adjustable by changing the structure of the ω-functional group. CONCLUSION: ω-Functionalized PCHD is a preferable precursor that can be utilized to obtain a new class of multifunctional hydrocarbon polymers containing six-membered rings in the main chain. Copyright © 2007 Society of Chemical Industry

各種のアイソタクチックメタクリル酸メチルのオリゴマーの量子化学計算による立体配座解析(エネルギー比計算)を行い観測結果と比較した．計算は非らせん条件(トランス 2 面角入力値:180°)で行った．3, 7 量体での最安定構造はそれぞれの観測結果とほぼ一致した．末端主鎖の立体配座は末端基のかさ高さに影響を受け，tert-ブチル基ではトランスが，プロトン，メチルまたは n-プロピル基では側鎖の回転を伴いゴーシュが安定であった．7, 9 および 11 量体の最安定構造は，7 量体の観測結果と同様，トランス鎖の中間にゴーシュをもつキンク構造であり，オリゴマーの結晶がポリマー(全トランスの 10/1 らせん)と異なることが推定された．11 量体のみがらせんがキンクした構造であり，らせん条件(-160°入力)で計算した均一らせんとのエネルギー差はわずかであった．この結果はポリマーが 10 モノマー単位のらせんであることを支持している．

The optical and electrical characteristics of soluble polyphenylene (PPH) homopolymers obtained by the complete dehydrogenation of poly(1,3-cyclohexadiene) (PCHD) are reported for the first time. The optical properties were strongly affected by the molar ratios of 1,2-/1,4-phenylene (Ph) units. The HOMO and LUMO energy levels were approximately −5.2 and −2.0 eV, and the microstructure did not influence those energy levels or the band gap energies. The generation of carriers (both electron and hole) in the polymer films was observed, and the drift mobility of electrons and holes was affected by the molar ratios of 1,2-/1,4-Ph units in the polymer chain. The drift mobility of electrons in PPH homopolymers with a high content of 1,4-Ph units was in the order of 10 −4 to 10 −5 (cm 2 /Vs). The I – V characteristics of soluble PPH homopolymers were controllable by the microstructure of PPH. The 1,2-Ph unit imparted appropriate solubility and toughness to the PPH homopolymers.

Chemical composition and its distribution of styrene (St)-ethyl acrylate (EA) copolymers synthesized by emulsion copolymerization under different monomer ratios and polymerization conditions were examined by 1H-NMR and high-performance liquid chromatography (HPLC), respectively, and compared with those of bulk copolymers. It was newly found that the chemical composition of copolymer at early stage is affected by the concentration of emulsifier (SDS, sodium dodecyl sulfate) and monomer/water ratio, and is almost independent of the concentration of initiator or polymerization temperature. The EA fraction decreased with the increase of SDS concentration and converged to the value calculated using distribution factor (fd) when SDS concentration was extrapolated to zero. These results indicate that the EA fraction in micelle decreased compared to the expected value from fd due to the interaction of EA monomer with emulsifier. From HPLC, it was found that each copolymer showed a sharp single peak at an early stage of polymerization indicating that no homopolymer or copolymer with different composition was produced.

The photon energy of vacuum ultraviolet (VUV) light is higher than the binding energy of some chemical bonds in organic molecules, such as C–C, C–H, or C–O. Therefore, VUV light is able to cause the scission of various bonds in polymer molecules, which can lead to the decomposition of the polymeric molecules. Degradation of polymers by VUV has been studied with the purpose of investigating damage to polymeric materials by VUV, developing new photoresist materials, revealing the degradation mechanism, and modifying polymer surfaces, etc. The degradation mechanism of poly(methyl methacrylate) (PMMA) has been extensively studied for evaluation as a new photoresist material. It was found that the side chain ester group is decomposed by VUV irradiation, leading to a polymer containing carboncarbon double bonds. In addition, scission of the main chain also occurred. If an ester group is easily cleaved by VUV, it may be expected that aliphatic polyesters, which contain ester groups in the main chain, will be degraded to small volatile molecules and may function as good photoresist materials. Aliphatic polyesters are soluble in common organic solvents, which enables good thin films to be easily formed. It is well known that aliphatic polyesters are easily degraded by biological reactions, and although many studies have been performed regarding the biodegradation of aliphatic polyesters, only a few studies have investigated degradation by irradiation with UV or VUV light. In this report, the degradation of aliphatic polyesters by VUV was investigated and compared with that of PMMA. The study concentrated on the reaction mechanism, the effect of oxygen and application of an external electric field during irradiation. EXPERIMENTAL

Soluble polyphenylene (PPH) homopolymers with a controlled polymer chain structure were synthesized for the first time by the complete dehydrogenation of poly(1,3-cyclohexadiene) (PCHD) having a 1,2-addition (1,2-CHD unit) and 1,4-addition (1,4-CHD unit). The reactivity of PCHD for dehydrogenation strongly depends on the polymer chain structure. The rate of dehydrogenation is fast on a long sequence of 1,4-CHD units, while it is considerably impeded by the presence of 1,2-CHD units in the polymer chain. With a reaction temperature higher than 90 °C, complete dehydrogenation of PCHD proceeds successfully to yield soluble PPH homopolymers. The polymers obtained are soluble in polar solvents. Therefore, the soluble PPH homopolymers appear to be polar macromolecules, and the conversion of polarity occurs during the dehydrogenation process. UV and fluorescence spectra clearly indicate the nature of a conjugated PPH homopolymer.

Photorefractive active block copolymers were successfully synthesized via an atom transfer radical polymerization of acrylate containing liquid crystalline moiety and hole transporting carbazole moiety. Resulting copolymers were characterized by gel permeation chromatography, NMR, and DSC. Copolymers afforded the transparent films showing birefringent nature. Photorefractive characteristics of copolymers with 2 wt% of trinitro- fluorenone as a photosensitizer were investigated by four wave mixing and two-beam coupling methods with a He-Ne laser. For the block copolymer, higher diffraction efficiency and larger coupling gain were observed compared with the corresponding statistical random copolymer.

The dehydrogenation of poly(1,3-cyclohexadiene)–polystyrene binary block copolymers obtained by anionic copolymerization with alkyllithium/amine systems was investigated for the first time. The dehydrogenation of the poly(1,3-cyclohexadiene) block, which was composed of 1,2-cyclohexadiene (1,2-CHD) and 1,4-cyclohexadiene (1,4-CHD) units, was strongly affected by the polymer chain structure. The existence of 1,2-CHD units prevented the dehydrogenation of the poly(1,3-cyclohexadiene) block in the binary block copolymer. The rate of dehydrogenation was fast on a long sequence of 1,4-CHD units, whereas it was relatively slow for 1,2-CHD/1,4-CHD (≈1/1) unit sequences. The bonding of the polystyrene block to the polymer chain effectively improved not only the rate of dehydrogenation of a long sequence of 1,4-CHD units but also that of the polymer chain with a high content of 1,2-CHD units. The dehydrogenation of a poly(1,3-cyclohexadiene) block containing a small number of 1,2-CHD units progressed via step-by-step reactions. The dehydrogenation of a long sequence of 1,4-CHD units proceeded as the first step. Subsequently, in the second step, the 1,2-CHD/1,4-CHD (≈1/1) unit sequences remaining in the polymer chain were dehydrogenated. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 3526–3537, 2006

The aggregation of poly(1,3-cyclohexadiene) (PCHD), obtained by anionic polymerization with alkyllithium/amine systems, was examined using size exclusion chromatography (SEC) and size exclusion chromatography coupled with a multiangle laser light scattering photometer (SEC-MALS). The PCHD polymer chain has a structure consisting of a main chain formed by 1,2-addition (the 1,2-CHD unit) and 1,4-addition (the 1,4-CHD unit). Mild stirring with relatively low temperature in the polymerization reaction forms an aggregation of PCHD. The molecular weight and molar ratio of 1,2-CHD/1,4-CHD units in the polymer chain strongly influence the aggregation of PCHD. In a high molecular weight PCHD, containing ∼50% 1,2-CHD units, an aggregation of the polymer was observed in tetrahydrofuran (THF) solution at room temperature. This aggregation of PCHD was soluble in 1,2,4-trichlorobenzene (TCBz) and could be separated into each polymer molecule. In contrast, a polymer chain with a high content of 1,4-CHD units having a relatively low cis-stereospecificity was easily soluble in THF and TCBz without aggregating. A long polymer chain structure with a high content of 1,2-CHD units is considered to be the reason for the generation of strong intermolecular forces contributing to the aggregation of PCHD with the solvophobic interactions. The degree of aggregation could be controlled by the conditions of the PCHD polymer solution. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1442–1452, 2006

We report the preparation of a new electroluminescent polymer by the oxidative coupling copolymerization of N-(4-n-butylphenyl)phenoxazine and 9,9-di-n-butylfluorene with ferric(III) chloride. The reaction yields soluble polymers with a weight-average molecular weight as high as 9000. The reactivity has been studied with respect to the reaction time, temperature, and feed ratio of the comonomers. Under optimum conditions, a copolymer with a 50% comonomer incorporation ratio can be obtained in a 75% yield. The polymers have been characterized with differential scanning calorimetry, cyclic voltammetry, and optical spectroscopy. A simple single-layer light-emitting-diode device of an indium tin oxide/polymer/Mg-Ag structure shows a luminance of 200 cd/m 2 at an 18-V operating voltage.

Sulfonation is one of the most commonly used methods for the surface modification of polymers. In this study, the sulfonation of poly(propylene) (PP) films with fuming sulfuric acid has been investigated with the focus onthe surface reaction. Analysis of the sulfonated PP films by X-ray photoelectron spectroscopy (XPS), attenuated total reflectance (ATR) infrared spectroscopy, and chemical modification demonstrated the formation of C=C double bonds and sulfate groups in the sulfonation process. These results and a comparison with low-density polyethylene (LDPE) films led us to propose a new sulfonation mechanism involving hydride abstraction and the formation of β-sultones.

The influence of the microstructure on the oxidation of poly(1,3-cyclohexadiene) (PCHD) homopolymer, obtained by anionic polymerization with alkyllithium/ amine systems, was investigated for the first time. PCHD has a structure consisting of a main chain formed by 1,2-addition (the 1,2-CHD unit) and 1,4-addition (the 1,4-CHD unit). The molar ratio of 1,2-CHD/1,4-CHD units in the polymer chain strongly influenced the extent of oxidation of PCHD. A polymer chain with a high content of 1,4-CHD units was easily oxidized by air and 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). In contrast, the progress of oxidation was prevented in the case of PCHD containing 52% of 1,2-CHD units.

Novel light-emitting copolymers containing 4-n-butyltriphenylamine and either anthracene, diphenylanthracene or perylene units were synthesized by polycondensation of two types of dibromides in the presence of bis(1,5-cyclooctadiene)nickel(0). The structure and incorporation ratio of the copolymers were determined by 1 H NMR analysis. From the results of yield and molecular weight measured by gel permeation chromatography, the reactivity of arene units with the 4-n-butyltriphenylamine unit shows decreasing tendency in the order diphenylanthracene>anthracene>perylene. The results of ionization potential measurement reveal that the copolymers have not only hole transporting ability but also electron transporting ability. Single-layer electroluminescent devices were fabricated using these copolymers as a charge transporting and light emitting layer.

A hyperbranched polymer (HBP) was prepared by the condensation polymerization of 4-hydroxymethylphenyldiphenylamine (TPA–CH2OH) and was compared with the corresponding linear polymer (LP) prepared by condensation polymerization of 4-methyltriphenylamine (MTPA) and formaldehyde (FA). It was found that the HBP had higher molecular weight with same molecular volume by using gel permeation chromatography (GPC) equipped with low angle laser light scattering (LALLS) and refractive index (RI) detectors. Electronic and optical properties of the two types of polymers were also examined. The two types of polymers showed almost same absorption in the UV–visible region, while HBP showed stronger emission than LP and a new excimer band at 470 nm. The cyclic voltammography showed that HBP had a redox peak around 1.22 V versus Ag/AgCl electrode, indicating that it has hole transporting ability. HBP is soluble in common organic solvents and forms good quality thin films. Their excellent morphological and thermal stability renders them advantageous for electroluminescence applications.

Photosulfonation of low-density polyethylene (LDPE) films by UV irradiation in the presence of gaseous sulfur dioxide (SO 2 ) and oxygen (O 2 ) was studied by attenuated total reflectance (ATR) infrared spectroscopy and X-ray photoelectron spectroscopy (XPS). The ATR and XPS analysis and chemical modification of UV-irradiated LDPE films demonstrated the generation of C=C double bonds and sultones in the reaction. These results indicated the possibility that sulfur trioxide (SO 3 ) was produced during the photosulfonation. New pathways for the SO 3 reaction with LDPE films, resulting in the formation of sulfonic acid groups, were proposed.

Sulfonation of low-density polyethylene (LDPE) films with fuming sulfuric acid was studied by X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance (ATR) infrared spectroscopy. The ATR spectra showed the formation of CC double bonds and multiple sulfur atom containing groups for the sulfonation of LDPE films. This led us to propose that the abstraction reaction of hydride ion by sulfur trioxide (SO3) in fuming sulfuric acid might account for the formation of the CC double bonds. It was considered that after the abstraction reaction, these double bonds react with SO3, resulting in the production of alkene sulfonic acids and sultones, along with the formation of sulfate groups as a result of reaction of the double bonds with sulfuric acid. Experimental data by treatment of the sulfonated LDPE films with KOH and thiourea supported the proposed idea, estimating the approximate molar ratio of the products. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2435–2442, 2004

A novel synthetic method for the preparation of high-molecular-weight conjugated polymers in presented. It consists of the oxidation copolymerization of different arenes with triphenylamine. The structure of the copolymers was characterized by 1 H and 13 C NMR spectra. The copolymers have good solubility in common organic solvents and are thermally stable. Photoluminescence (PL) spectra (see Figure) showed that the color of emission depends on the type of arene units in the copolymer chain. Cyclic voltammetry (CV) measurements revealed electrochemical activity of the copolymers.

High molecular weight poly(4-alkyltriphenylamine) was synthesized by chemical oxidation polymerization. 13 C NMR spectra of the obtained polymers revealed that coupling reaction occurred exclusively at the para -position of unsubstituted N -phenyl rings. Poly(4- n -butyltriphenylamine) (P- n BTPA) showed better solubility and processability than polymers prepared from 4-methyltriphenylamine (MTPA) and 4- t -butyltriphenylamine ( t BTPA) because of the high molecular weight and the flexible long n -butyl group in the side chain. Thus, P- n BTPA allows us to prepare the film from its solution in organic solvent with ease. The rigid structure of polymeric backbone affords high glass transition temperature of 182 °C, indicating high thermal stability. Extended conjugation over polymer chain results in red shift of UV absorption up to 375 nm and low ionization potential compared to monomer. The results of the ionization potential measurement and the redox behavior suggest that the polymer has great potential as a hole-transporting material (HTM). The drift mobility of P- n BTPA measured by a standard time-of-flight (TOF) method was found to be of the order of 10 −5 cm 2 /(V s). The results of the photoconductivity measurement revealed that the photoconductivity of P- n BTPA showed much higher than that of poly( N -vinylcarbazole).

Monomers containing N,N',N,N'-tetraphenylbenzidine (TPD) were prepared by introducing two alkyl or alkoxy substituents into the p-position of two of the four phenyl groups in the triphenylamine unit. The monomers were copolymerized with 1,4-divinylbenzene (DVB) in the presence of p-toluenesulfonic acid and Lewis acids, such as SnCl 4 and BF 3 . The polymerization conditions and the catalyst types showed a marked influence on yield, molecular weight and even polymer structure. 1 H NMR measurements revealed that, by using p-toluenesulfonic acid as a catalyst, the linkage between the TPD unit and DVB occurs at the p-position of the phenyl group and at the m-position of the tolyl group in the TPD unit, whereas, with SnCl 4 or BF 3 catalyst, substitution occurs exclusively at the p-position of TPD. All polymers are soluble in common organic solvents, which allows the preparation of thin films of good quality. The rigid structure of the polymeric backbone results in a high thermal stability up to 400 °C. The results of ionization potential measurements and the redox behavior showed that the introduction of the TPD unit into this kind of polymer backbone does not change its electronic structure. On the basis of high electroactivity, the polymers were successfully used as hole transport layers in two-layer electroluminescence devices.

N,N′-bis(4-alkylphenyl)-N,N′-diphenylbenzidine (alkyl-TPD) was reacted with 1,4-bischloromethylbenzene, 9,10-bischloromethylanthracene (BCA), 4,4′-bis(chloromethyl)-1,1′-biphenyl (BCP) or 2,7-bis(bromomethyl)-9,9-di-n-butylfluorene (BBF) by condensation polymerization using Friedel–Crafts reaction. The polymers were obtained in high yield and high molecular weight. TPD having two methyl substituents showed higher reactivity and larger gel content than one having two butyl substituents. The structure of polymers was determined by 1 H NMR spectroscopy. It was found that all polymers showing two methylene signals arises from benzyl proton, which indicates that the polymerization occurred not only at the para-position of phenyl group but also at the meta-position of alkylphenyl group in TPD derivatives. All polymers had almost the same oxidation potential as that of TPD itself. The polymer containing anthracene unit showed not only oxidation but also reduction peak.

Hole transporting polymers were prepared by condensation polymerization of triphenylamine and N,N,N',N'-tetraphenylbenzidine (TPD) having alkyl group with aldehydes in the presence of p-toluenesulfonic acid. The obtained polymers had molecular weight higher than 10,000 and good film formation ability. It was found that the aromatic amine monomers were connected with aldehyde monomer at the p-position of the phenyl group. TPD-aldehyde polymers had almost the same UV absorption and redox potentials as those of TPD monomer indicating that the electronic structure of amine unit did not change by the polymerization. The hole transporting mobility was in the range of 10 -3 -10 -6 cm 2 /Vs. The electroluminescent device consisting of ITO/TPD polymer/Alq/Mg-Ag had a maximum luminance of 9000 cd/m 2 .

New triarylamine-based polymers have been synthesized by polyaddition of 4-tolyldiphenylamine (TDPA) with 1,4-divinylbenzene (DVB) or 1,3-diisopropenylbenzene (IPB) in the presence of p-toluenesulfonic acid. 1H NMR spectra revealed that DVB units were linked to TDPA units not only at p-position but also at m-position to aryl group in TDPA-DVB polymer. On the other hand, IPB was less reactive and TDPA-IPB polymer was achieved only in a p-linkage. The incorporation of DVB or IPB did not significantly affect the electronic structure of TDPA unit as confirmed by UV spectra and cyclic voltammetry. From differential scanning calorimetric (DSC) measurements, glass transition temperatures of TDPA-DVB and TDPA-IPB polymers were estimated to be 169°C and 132°C, respectively. The resulting polymers have good solubility in conventional organic solvents (e. g. chloroform, tetrahydrofuran and toluene).

New hole transport polymers have been synthesized by condensation polymerization of 4-tolyldiphenylamine (TDPA) with various types of aldehyde. The reaction conditions have been investigated to yield polymers with high molecular weight. It is found that the molecular weight and yield of the TDPA–aldehyde polymers strongly depend on the electron donor–acceptor nature of the substituent on the aromatic ring of the aldehyde monomer. Structural characterization by 1H NMR spectroscopy shows that the addition condensation reaction occurs exclusively at the para position of TDPA. The electrochemical and optical properties of polymers have been investigated by cyclic voltammetry and UV–vis spectroscopy. Cyclic voltammograms of all polymers show well-defined pairs of reduction and oxidation peaks, indicating that the polymers are electrochemically active. All polymers show low conductivities of magnitude 10−14 S cm−1. Differential scanning calori-metry measurements reveal that TDPA–aldehyde polymers exhibit glass transitions in the range 170–230 °C. These polymers possess good solubility and the films show sufficient morphological stability. © 2001 Society of Chemical Industry

4-Tolyldiphenylamine (TDPA) and N,N′-diphenyl-N,N′-bis(4-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD), were reacted with benzaldehyde (BA) using p-toluenesulfonic acid as a catalyst to yield linear polymers. The polymers were reacted with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) in tetrahydrofuran (THF) at room temperature. 1H-NMR showed that all the methine protons in the residue of BA were completely removed at the mole ratio of repeating unit : DDQ, 2 : 1. The resulting polymers showed good solubility in chloroform or THF. The reacted TDPA-BA and TPD-BA polymers gave new UV absorption peaks at 697.0 and 722.5 nm and showed reversible redox potentials about 0.994 and 1.021 V, respectively. Direct current (d.c.) conductivity of the reacted polymers was in the range of 10−11 S/cm, which is more than two orders higher than the unreacted polymers. The polymer showed pentad split electron spin resonance (ESR) signal, whose concentration was one in 670 or 230 repeating unit for TDPA-BA and TPD-BA polymers, respectively. Copyright © 2001 John Wiley & Sons, Ltd.

Synthesis of New Hole Transport Polymers Based on N,N ′-Diphenyl- N,N ′-bis(4-methylphenyl)-1,4-phenylenediamine

A new acrylate bearing N,N′-diphenyl-N,N′-bis(4-methylphenyl)-[1,1′-biphenyl]-4,4′-diamine (TPD) was synthesized to apply for hole transport layer of an electroluminescent (EL) device. The thin film of this monomer was fabricated with physical vapor deposition. The obtained thin film was preliminarily irradiated with UV light and then heated up to 400 K in vacuum. The resulting polymer film, 60 nm thick, which had a polymer conversion of 96% had a smooth surface. This even surface could be maintained up to the heating of 420 K. These processes of deposition and polymerization were monitored with in situ reflection infrared spectroscopy. The EL device made of polymer thin film had three times higher efficiency than that from the monomer thin film.

Acrylate and methacrylate type monomers containing thioxanthene derivative were synthesized and radically polymerized to yield electron transporting polymers. The obtained polymers are soluble in common solvents such as tetrahydrofuran (THF), chloroform, dimethylformamide (DMF). Cyclic voltammograms of all polymers showed two well-defined pairs of reduction and oxidation peaks indicating that polymers are electrochemically active. The polymers with dicyanomethylated thioxanthene derivative were more easily reduced than those with unmodified one because of the strong electron-withdrawing effect of dicyanomethyl groups, while the latter showed higher electron drift mobility than the former. Drift mobility was discussed in relation to the structure of the lowest unoccupied molecular orbital (LUMO) and the electron distribution. A well-balanced distribution of electrons plays an important role for a high-mobility material.

A thin film of triphenylaminemethylacrylate was fabricated by physical vapor deposition onto an indium–tin oxide substrate over a temperature range from 230 to 290 K. This thin film was subsequently polymerized by UV irradiation in vacuum with the aim of fabricating electroluminescent devices. Polymerization of the thin film in vacuum was investigated by in-situ FT–IR reflection absorption spectroscopy. UV irradiation achieved a polymer conversion of around 100%. Though the polymerization time increased at the lower temperature of the substrate, the surface flatness of the thin film was improved. The polymerization mechanism was elucidated as a simple radical polymerization on the basis of the order of monomer consumption rate. The number-average molecular weight increased with decreasing UV intensity.

4-Methyltriphenylamine was oxidatively polymerized in chloroform (CL) or propylene carbonate (PC) in the presence of ferric chloride (FeCl3) at 50°C. Polymerization proceeded more rapidly and the molecular weight of the resulting polymer was higher in CL than in PC due to the higher oxidation potential of the solution. The linear structure was confirmed by 13C NMR, and the resulting polymer exhibited high thermal stability and electrochemical activity.

Triphenylamine (TPA) was reacted with carbonyl compounds such as formaldehyde, butyraldehyde, benzaldehyde, and acetone in the presence of an acid catalyst. 1 H and 13 C NMR spectra revealed that the carbonyl compounds react only at the p-position of TPA. The reactivity of formaldehyde with TPA is lower than that with phenol. If equal molar amounts of formaldehyde are reacted, however, TPA condensation proceeds to high molecular weight polymers, while phenol provides only low molecular weight compounds (up to 1000). TPA-aldehyde polymers have glass transition temperatures in the range of 135-176°C. These polymers show good solubility and sufficient stability after film formation.

Two methacrylate monomers containing fullerene on the side chain (AHMA-C60 or AEMA-C60) were synthesized by reacting 4-azidobenzoyloxy-hexyl and -ethyl methacrylate, respectively, with fullerene. 1H and 13C NMR spectra of these monomers revealed each was a mixture of [6,6] bridged azamethanofullerene derivative and azafulleroid derivative resulting from [5,6] additions. The monomers were later copolymerized with t-butyl methacrylate. In the case of anionic copolymerization using a Grignard reagent, the monomers were incorporated in the polymer chain via vinyl chain reactions, resulting in a charm bracelet type fullerene polymer. The copolymer composition was found almost equal to the composition of monomers fed. In radical copolymerizations, low molecular weight oligomers were obtained in low yields, and contained almost equal amounts of the vinyl group to the fullerene monomer incorporated in the polymer, indicating that the fullerene unit played a role of an inhibitor or a degradative chain transfer agent.

Triphenylamine derivatives, such as 4-tolyldiphenylamine (TDPA) and N , N ′-diphenyl- N , N ′-di-(4-methylphenyl)-1,4-phenylenediamine (PDA), were reacted with paraformaldehyde (FA) using p -toluenesulfonic acid catalyst to yield linear polymers. 1 H -NMR and 13 C -NMR spectra revealed that FA reacted exclusively at the p -position of triphenylamine derivatives, and TDPA and PDA units were linked not only by a methylene linkage but also by a methylene ether linkage. The PDA–FA polymer contained higher amount of methylene linkage as compared to TDPA—FA polymer. Additionally, the number of methylene ether linkage was increased with the concentration of paraformaldehyde. The glass transition temperatures of PDA–FA and TDPA–FA were at 204°C and 111°C, respectively. These polymers were soluble in conventional solvents such as chloroform, toluene, etc., and showed sufficient morphological stability after the film formation. The hole drift mobility of PDA–FA was found to be in the order of 10 −6 cm 2 /V s.

The effect of sodium dodecyl sulphate (SDS) on the formation of inverse micro-emulsion toluene/sodium bis(2-ethylhexyl)sulphosuccinate (AOT)/ water/acrylamide (AAm)/SDS and on polymerization of acrylamide initiated by oil soluble dibenzoyl peroxide was studied. The presence of SDS shifts the value of the volume fraction of aqueous phase (Φ aw ) at which a two-phase Winsor II system forms, to higher values. It was shown that an increase of the mass ratio of SDS/water led to a decrease of acrylamide polymerization rate, of polyacrylamide particle size and of polyacrylamide molecular mass distribution. It was also found that in the presence of SDS, a nearly constant value for acrylamide polymerization rate in inverse micro-emulsion in the range of Φ aw values between 5% and 50% can be obtained. The polymerization kinetics and polymer particle formation were explained as consequences of the initiation of acrylamide polymerization in two reaction loci-in inverse micelles and in the oil macrophase of the inverse micro-emulsion.

Acrylate type of monomer having tetraphenyldiaminobiphenyl (TPD) unit was prepared and was homo- and copolymerized with n-butyl acrylate using AIBN as an initiator. Electrochemical property of synthesized polymers was evaluated with cyclic voltammetry. All polymers exhibited the irreversible oxidation peak at 1.1 V in the initial cycle due to the oxidative coupling of TPD unit and two pairs of reversible oxidation and reduction peaks were observed in the subsequent cycles. Drift mobilities of synthesized polymers were in the range of 10-5 cm2/V s at applied field of 1.6 × 105 V/cm and were 100 times higher than that of PVK. Photorefractivity of polymers doped with 4-(N,N-diethylamino)-β-nitrostyrene (nonlinear chromophore) and fullerene (C60, charge generator) was investigated with two-beam coupling (2BC) technique. A 100-μm thick composite film showed gains of 9 and 40 cm-1 at an external electric fields of 50 and 70 V/μm, respectively. The phase shift between the index grating and interference pattern w...

Styrene-divinylbenzene copolymer get beads in a swollen state were characterized with a proton nuclear magnetic resonance spectroscopy ( 1 H-NMR) using chloroform as a probe. The signal of chloroform was observed as doublet peaks and the peak at higher magnetic field was assigned to chloroform inside the get beads and the other at lower magnetic field to one outside the get beads. NMR parameters such as signal chemical shift, intensity, line width, and shape were investigated in relation to the characteristics of get beads such as the swelling ratio, the diameter, pore size, and crosslinking density. The relative intensity of the signal due to chloroform inside the get beads increased with the amount of diluent used in preparation of the beads. With the decrease of the diameter of the beads, two signals became closer, because the rate of exchange between the solvent molecules inside and outside increased. The pore size also influenced the shape of the doublet peaks. As the pore size increased, the two peaks overlapped due to the decrease of the portion of chloroform that interacts with the polymer matrix. The crosslinking density did not influence the peak shape although the dynamics of chloroform were affected by the crosslinking density.

NMR Measurement of Identical Polymer Samples by Round Robin Method IV. Analysis of Composition and Monomer Sequence Distribution in Poly(methyl methacrylate- co -acrylonitrile) Leading to Determinations of Monomer Reactivity Ratios