Synthesis and photopolymerization characterization of a novel difunctional photoinitiator

A novel difunctional photoinitiator HBP‐TDI‐HBP based on 4‐hydroxybenzophenone (HBP) and toluene‐2,4‐diisocyanate (TDI) was synthesized and characterized by ¹H NMR and UV–Vis absorption spectroscopy. The kinetics of photopolymerization was studied by real‐time infrared spectroscopy. It showed that HBP‐TDI‐HBP was a more effective photoinitiator than benzophenone. When this photointiator and amine were used to efficiently initiate polymerization of acrylates and methacrylates, both rate of polymerization and final conversion increased with increase of HBP‐TDI‐HBP concentration, light intensity, and amine concentration. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

New antimicrobial agents: The synthesis of Schiff base polymers containing transition metals and their characterization and applications

A new polymeric Schiff base containing formaldehyde and 2‐thiobarbituric acid moieties was synthesized by the condensation of a monomeric Schiff base derived from 2‐hydroxyacetophenone and hydrazine. Polymer–metal complexes were also synthesized by the reaction of the polymeric Schiff base with Mn(II), Co(II), Ni(II), Cu(II), and Zn(II) acetate. The polymeric Schiff base and its polymer–metal complexes were characterized with magnetic moment measurements, elemental analyses, and spectral techniques (infrared, ¹H‐NMR, and ultraviolet–visible). The thermal behaviors of these coordination polymers were studied by thermogravimetric analysis in a nitrogen atmosphere up to 800°C. The thermal data revealed that all of the polymer–metal complexes showed higher thermal stabilities than the polymeric Schiff base and also ascribed that the Cu(II) polymer–metal complex showed better heat resistant properties than the other polymer–metal complexes. The antimicrobial activity was screened with the agar well diffusion method against various selected microorganisms, and all of the polymer–metal complexes showed good antimicrobial activity. Among all of the complexes, the antimicrobial activity of the Cu(II) polymer–metal complex showed the highest zone of inhibition because of its higher stability constant and may be used in biomedical applications. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011     

The synthesis and application of Pb‐doped GLYMO/chelated‐zirconium complex coating materials for UV‐light absorption

New glass coating materials containing γ‐glycidoxypropyltrimethoxy‐silane/zirconium(IV)‐n‐propoxide(2‐methoxyethylacetoacetate)/lead(II) nitrate were developed for UV‐light absorption by sol‐gel process. The effect of agitation time, temperature, and Zr complex and Pb²⁺ ion concentrations on UV light absorption were investigated. Zr complex was characterized by using ¹H‐NMR, ¹³C‐NMR, and FTIR spectroscopy. Ultraviolet visible spectroscopy was utilized to determine the optical properties of coating materials. Results showed that coated glass has very low transmission in the UV region (300–400 nm) relative to uncoated glass, especially at 150°C for 15 h agitation. UV light transmission of coated glasses treated at 80, 100, 450, or 500°C was not different from uncoated glass. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 99: 1175–1179, 2006     

Cut‐out filter for ultraviolet radiation from poly(vinyl alcohol)

The effects of ultraviolet (UV) radiation and thermal annealing on the optical and mechanical properties of polyvinyl alcohol (PVA) were studied. Pure PVA samples were prepared by casting technique. Xenon arc lamp was used to irradiate the sample. The irradiated PVA sample was heated at 150°C for 2 h. The optical and mechanical properties of original, irradiated, and irradiated and then heated samples were measured. The irradiated and then heated sample showed lower transmission in the wavelength range from 190 to 320 nm and the transmission was higher in the visible region than the original and irradiated samples. The stress–strain measurements were performed. Modulus of elasticity of the double‐treated sample was approximately four times higher than that of original sample. The obtained results show the possibility of using this sample as cut‐out filter for UV radiation. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 84: 1295–1299, 2002; DOI 10.1002/app.10486     

A combined experimental and theoretical study on vibrational and optical properties of copolymer incorporating thienylene‐dioctyloxyphenyle‐thienylene and bipyridine units

Optical properties of conjugated copolymer incorporating thienylene‐dioctyloxyphenyle‐thienylene and bipyridine units prepared by Stille coupling reactions in the ground and lowest singlet excited states were calculated with Time Dependent Density Functional Theory (TD‐DFT), CIS/3‐21G*, and semiempirical (ZINDO) methods. The complementarities and the good agreement between theoretical and experimental results have permitted us to describe electronic structure and to predict a correlation between structure and properties of this new copolymer. Then, on the basis of these results, we show that this copolymer could be exploited as an active layer in optoelectronic devices. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis,characterization, and photochemical properties of chromophores containing photoresponsive azobenzene and stilbene

In this article, we describe the synthesis of two azobenzene and two stilbene‐based diacetylene chromophores containing terminal electron‐donating (? OCH₃) and electron‐withdrawing (? NO₂) terminal groups with esterification reactions. The target compounds were characterized by NMR, X‐ray diffraction (XRD), absorption, and photoluminescence spectroscopies. We investigated the structural effects of these photochromic compounds on the E–Z photoisomerization and 1,4‐addition under UV irradiation. 4‐[(4‐Nitrophenyl)‐diazenyl]phenyl pentacosa‐10,12‐diynoate, incorporating the electron‐withdrawing nitro group (? NO₂), underwent the fastest rate of Z‐to‐E isomerization in darkness via a rotation mechanism. Our results demonstrate that self‐assembled azobenzene Z isomers exhibited enhanced fluorescence under UV irradiation. XRD spectroscopy identified bilayer packing by the polydiacetylene films after 1,4‐addition. Chromophores comprising the diacetylene group presented moderate photochromic stability upon 1,4‐addition, changing from their original yellowish color to form a blue phase. These synthesized compounds may be useful in the development of new and unique functional materials that exhibit bistable photochromism. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012     

Synthesis and structural characterization of a new polysiloxane with second‐order nonlinear optical effect

A new polysiloxane ( P2 ), with a high density of the indole‐based chromophore and carbazolyl side groups, was prepared. Thus a polysiloxane ( P1 ), with indole and carbazolyl groups as side chains, was first synthesized through a hydrosilylation reaction, and then the post‐azo coupling of p‐nitrobenzenediazonium fluoroborate toward the indole ring gave the mulifunctional indole‐based chromophore‐functionalized polysiloxane ( P2 ). Molecular structural characterization for the polymers was determined by ¹H‐NMR, IR, and UV–visible spectra, gel permeation chromatography, and differential scanning calorimetry. The polymers were easily soluble in common organic solvents. The poled film of P2 revealed a resonant d₃₃ value of 27 pm/V by second‐harmonic generation measurements. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 94: 769–774, 2004     

Synthesis and characterization of processable polyaniline doped with novel dopant NaSIPA

Aniline has been polymerized in the presence of a novel dopant sodio‐5‐sulfo‐isophthallic acid (NaSIPA), via the chemical oxidative polymerization route. The thermal stability and processability of polyaniline prepared by indirect method (PD1) have been improved significantly (290°C) as compared to polyaniline doped with conventional inorganic dopants like HCl or H₂SO₄, without much loss of electronic conductivity (5.07 S/cm in PD1). This suggests its use for melt blending with engineering thermoplastics. However, polyaniline prepared by direct method (PD2) can be melt‐blended only with conventional thermoplastics like polyethylene, polypropylene, polystyrene, etc. Low‐temperature studies reveal the 1‐D variable range hopping as a conduction mechanism for direct polymer (PD2), with parameters T_o and σ_o as 4112 K and 15.1 S/cm, respectively. However, for indirectly doped polymer (PD1) Arrhenius‐type model, having parameters |(E_F ? E_C)| and σ_C as 0.04 eV and 28.4 S/cm, respectively, it suited well. The coherence length as found from XRD data was around 28.8 nm for PD1 and 25.2 nm for PD2. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci 2008     

Preparation and characterization of novel optically active polyurethanes containing 1,1′‐binaphthol

Novel optically active polyurethanes (BPUs) based on chiral 1,1′‐binaphthol were synthesized via direct hydrogen transfer addition polymerization. The polymers were analyzed by FTIR, ¹H NMR, DSC‐TGA, CD spectra.The results showed that the specific rotation [α]²⁵_D were ?78.0° and +54.6° for the S‐BPU and R‐BPU respectively, and these polymers showed better thermal stability. The circular dichroism spectra of the chiral polymers were almost identical except that they gave opposite signals at each wavelength, and the infrared emissivity values of the S‐BPU and R‐BPU were 0.618 and 0.682, they displayed low infrared emissivity. Meantime the polymers implanted with PEG group exhibit better solubility, however thermal stability reduced to some extent. Some properties of the new optically active polyurethanes were reported. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Synthesis and characterization of novel two‐component conjugated polythiophenes with 3‐octyl and 3‐isooctylthiophene side chains

With copolymerization functionalization, a novel solution‐processable polymer, poly{(3‐octylthiophene)‐co‐[3‐(2‐ethyl‐1‐hexyl)thiophene]} (P3OTIOT), combining the electrochemical properties of poly(3‐octylthiophene) (P3OT) and poly[3‐(2‐ethyl‐1‐hexyl)thiophene] (P3IOT) was synthesized by the FeCl₃‐oxidative approach. The characterization of the polymers included Fourier transform infrared, ¹H‐NMR, gel permeation chromatography, thermogravimetric analysis (TGA), ultraviolet–visible spectroscopy, and photoluminescence (PL). P3OTIOT had excellent solubility in common organic solvents. Investigations of the optical properties showed that the optical band‐gap energy of P3OTIOT was similar to that of P3OT (2.43 eV) at 2.45 eV and 6% lower than that of P3IOT in CHCl₃ solutions. The bandwidth of the P3OTIOT absorption approached that of P3OT, ranging from 370 to 570 nm, and the emission maximum of P3OTIOT was only 50 nm blueshifted with respect to that of P3OT. However, the PL intensity of P3OTIOT was 7 times higher than that of P3OT. TGA studies showed that P3OTIOT had very good thermal stability, losing 5% of its weight on heating to 300°C. It is suggested that P3OTIOT has low band‐gap energy, a high PL quantum yield, and processability. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 1169–1175, 2007     

Preparation and electro‐optical behaviors of polymer stabilized liquid crystal cells with chiral matrices derived from (−)‐camphor

Novel chiral monomers derived from (?)‐camphor and difunctional monomers with biphenyl segments were synthesized. The molecular structures were identified using FTIR, NMR, and elemental analyses. Surface pretreated polymer stabilized cholesteric texture (PSCT) cells with various chiral nematic components were prepared. According to theory, they are kind of reversed mode PSCT cells. The helical twisting power (HTP) and pitches of the PSCT cells were evaluated. The polarized optical microscopic (POM) textures and the dependence of the optical properties on the applied voltage of the PSCT cells were investigated. The reflection band of the PSCT cells before and after UV irradiation were estimated. A blue shift of selective reflection of the PSCT cells was obtained after UV irradiation. PSCT cells with various reflecting colors and the dependence of the transmittance of the cells on applied voltage were investigated. Real image recording through a mask as well as the transmittance of PSCT cells controlled by applied voltage were also confirmed. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci 98: 88–96, 2005     

A highly active and stable Fe-Mn catalyst for slurry Fischer–Tropsch synthesis

A highly stable and active Fe-Mn catalyst for slurry Fischer–Tropsch synthesis (FTS) was prepared and scaled up for the application in the industrial pilot plant at Institute of Coal Chemistry (ICC), Chinese Academy of Sciences (CAS). One Lab-scale catalyst and one scaled-up catalyst are introduced in the present paper. The particle size of the Lab-scale catalyst is about 5–15 μm, while it is increased to 30–90 μm for the scaled-up catalyst. Simultaneously, the morphology of the catalyst was greatly improved after the catalyst being scaled up. Both the Lab-scale and scale-up catalysts show high FTS activity. CO conversion of the Lab-scale catalyst and the scaled-up one are over 70.0% (H₂/CO = 0.67, 275 °C, 1.5 MPa and 3000 h⁻¹) and 55.0% (H₂/CO = 0.67, 260 °C, 1.5 MPa and 2000 h⁻¹), respectively. The catalysts also possess excellent stability, no obvious deactivation was observed during stable run of 4200 h and 1200 h on stream for the two catalysts. However, the Lab-scale catalyst produced more methane (about 8–10 wt%) and C_2–4 (22–30 wt%) and less C5⁺ hydrocarbon (55–70 wt%). Meanwhile, the hydrocarbon distribution of the catalyst was greatly improved for after the catalyst being scaled up, and the distribution of hydrocarbon products become much preferable. The selectivity to methane was well controlled at about 5 wt%, and the sum of and was increased to 91–93 wt%. On the whole, the scaled-up catalyst satisfies the requirements of the application for FTS in the industrial pilot plant of slurry bubble column reactor (SBCR) at ICC, CAS.     

Preparation and characterization of PS‐PMMA/ZnO nanocomposite films with novel properties of high transparency and UV‐shielding capacity

High transparent and UV‐shielding poly (styrene)‐co‐poly(methyl methacrylate) (PS‐PMMA)/zinc oxide (ZnO) optical nanocomposite films were prepared by solution mixing using methyl ethyl ketone (MEK) as a cosolvent. The films were characterized by X‐ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), ultraviolet–visible (UV–vis) spectra, high‐resolution transmission electron microscopy (HR‐TEM), and atomic force microscope (AFM). Cross‐section HR‐TEM and AFM images showed that the ZnO nanoparticles were uniformly dispersed in the polymer matrix at the nanoscale level. The XRD and FTIR studies indicate that there is no chemical bond or interaction between PS‐PMMA and ZnO nanoparticles in the nanocomposite films. The UV–vis spectra in the wavelength range of 200–800 nm showed that nanocomposite films with ZnO particle contents from 1 to 20 wt % had strong absorption in UV spectrum region and the same transparency as pure PMMA‐PS film in the visible region. The optical properties of polymer are greatly improved by the incorporation of ZnO nanoparticles. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Blue‐light‐emitting poly(arylene ethynylenes) containing alternating sequences of biphenylene or fluorenediyl and p‐phenylene moieties linked through triple bonds

Two new poly(arylene ethynylenes) were synthesized by the reaction of 1,4‐diethynyl‐2.5‐dioctylbenzene either with 4,4′‐diiodo‐3,3′‐dimethyl‐1,1′‐biphenyl or 2,7‐diiodo‐9,9‐dioctylfluorene via the Sonogashira reaction, and their photoluminescence (PL) and electroluminescence (EL) properties were studied. The new poly(arylene ethynylenes) were poly[(3,3′‐dimethyl‐1,1′‐biphenyl‐4,4′‐diyl)‐1,2‐ethynediyl‐(2,5‐dioctyl‐1,4‐phenylene)‐1,2‐ethynediyl] (PPEBE) and poly[(9,9‐dioctylfluorene‐2,7‐diyl)‐1,2‐ethynediyl‐(2,5‐dioctyl‐1,4‐phenylene)‐1,2‐ethynediyl] (PPEFE), both of which were blue‐light emitters. PPEBE not only emitted better blue light than PPEFE, but it also performed better in EL than the latter when the light‐emitting diode devices were constructed with the configuration indium–tin oxide/poly(3,4‐ethylenedioxythiophene) doped with poly(styrenesulfonic acid) (50 nm)/polymer (80 nm)/Ca:Al. The device constructed with PPEBE exhibited an external quantum efficiency of 0.29 cd/A and a maximum brightness of about 560 cd/m², with its EL spectrum showing emitting light maxima at λ = 445 and 472 nm. The device with PPEFE exhibited an efficiency of 0.10 cd/A and a maximum brightness of about 270 cd/m², with its EL spectrum showing an emitting light maximum at λ = 473 nm. Hole mobility (μ_h) and electron mobility (μ_e) of the polymers were determined by the time‐of‐flight method. Both polymers showed faster μ_h values. PPEBE revealed a μ_h of 2.0 × 10^?4 cm²/V·s at an electric field of 1.9 × 10⁵ V/cm and a μ_e of 7.0 × 10^?5 cm²/V·s at an electric field of 1.9 × 10⁵ V/cm. In contrast, the mobilities of the both carriers were slower for PPEFE, and its μ_h (8.0 × 10^?6 cm²/V·s at an electric field of 1.7 × 10⁶ V/cm) was 120 times its μ_e (6.5 × 10^?8 cm²/V·s at an electric field of 8.6 × 10⁵ V/cm). The much better balance in the carriers' mobilities appeared to be the major reason for the better device performance of PPEBE than PPEFE. Their highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels were also a little different from each other. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 100: 299–306, 2006     

Synthesis and characterization of novel optically active and flame‐retardant heterocyclic polyimides

Tetrachlorophthalic anhydride (1) was reacted with L ‐leucine (2) in toluene solution at refluxing temperature in the presence of triethylamine and the resulting imide‐acid (4) was obtained in quantitative yield. The compound (4) was converted to the N‐(tetrachlorophthaloyl)‐L ‐leucine acid chloride (5) by reaction with thionyl chloride. The reaction of this acid chloride (5) with isoeugenol (6) was carried out in chloroform and novel optically active isoeugenol ester derivative (7) as a chiral monomer was obtained in high yield. The compound (7) was characterized by ¹H‐NMR, IR, Mass and elemental analysis, and then was used for the preparation of model compound (10) and polymerization reactions. 4‐Phenyl‐1,2,4‐triazoline‐3,5‐dione, PhTD (8) was allowed to react with compound (7). The reaction is very fast, and gives only one diastereomer of (10) via Diels–Alder and ene pathways in excellent yield. The polymerization reactions of novel monomer (7) with bistriazolinediones [bis‐(p‐3,5‐dioxo‐1,2,4‐triazolin‐4‐ylphenyl)methane (11) and 1,6‐bis‐(3,5‐dioxo‐1,2,4‐triazolin‐4‐yl)hexane] (12) were carried out in N,N‐dimethylacetamide (DMAc) at room temperature. The reactions are exothermic, fast, and give novel optically active polymers (13) and (14) via repetitive Diels–Alder‐ene polyaddition reactions. The resulting polymers are optically active, thermally stable, and flame resistant. All of the above compounds were fully characterized by IR, ¹H‐NMR, elemental analysis, and specific rotation. Some structural characterization and physical properties of these novel heterocyclic polyimides are reported. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 76: 240–248, 2000     

Synthesis and characterization of novel thermally stable and optically active poly(amide‐imide)s derived from N,N′‐(4,4′‐diphthaloyl)‐bis‐L‐leucine diacid and aromatic diamines

A new diacid containing optically active functional groups, N,N′‐(4,4′‐diphthaloyl)‐bis‐L ‐leucine diacid ( 3 ), was synthesized and used in a preparation of a series of poly(amide‐imide)s (PAIs) by direct polycondensation with various aromatic diamines in N‐methyl‐2‐pyrrolidinone (NMP). All polymers derived from diacid ( 3 ) were highly organosoluble in the solvents like N‐methyl‐2‐pyrrolidinone, N,N‐dimethylacetamide, N,N‐dimethylformamide, dimethyl sulfoxide, tetrahydrofuran, γ‐butyrolactone, cyclohexanone, and chloroform at room temperature or upon heating. Inherent viscosities of the PAIs were found to range between 0.34 and 0.61·dL g^?1. All the PAIs afforded flexible and tough films. The glass‐transition temperatures of these PAIs were recorded between 212 and 237°C by differential scanning calorimetry, and the 10% weight loss temperatures were ranging from 372 to 393°C and 336–372°C under nitrogen and air, respectively. The polyimide films had a tensile strength in the range of 63–88 MPa and a tensile modulus in the range of 1.2–1.7 GPa. Optically active PAIs exhibited specific rotations in the range of ?10.58° to ?38.70°. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Synthesis of novel polyimides containing side‐chain azo‐2‐naphthol moieties

An amine‐ester derivative of isoeugenol was prepared in three steps. This amine‐ester was converted to diazonium salt and subsequently was reacted with 2‐naphthol and a novel isoeugenol ester‐azo derivative as a new monomer was obtained in quantitative yield. This monomer was characterized by high‐field ¹H‐NMR, IR, and elemental analysis and then was used for the preparation of model compound and polymerization reactions. 4‐Phenyl‐1,2,4‐triazoline‐3,5‐dione was allowed to react with this new monomer. The reaction was very fast and gave only one double adduct by Diels–Alder and ene pathways in excellent yield. The polymerization reactions of novel monomer with bistriazolinediones [bis(p‐3,5‐dioxo‐1,2,4‐triazolin‐4‐ylphenyl)methane and 1,6‐bis(3,5‐dioxo‐1,2,4‐triazolin‐4‐yl)hexane] were carried out in N,N‐dimethylacetamide at room temperature. The reactions were exothermic, fast, and gave novel heterocyclic polyimides by repetitive Diels–Alder‐ene polyaddition reactions. Some structural characterization and physical properties of these novel heterocyclic polyimides are reported. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 89: 1942–1951, 2003     

A Modified Method for the Determination of N‐Nitrosodiethanolamine in Coconut Diethanolamide Using HPLC with Dual‐Wavelength UV–Vis Detector

A simple and novel method based on high‐performance liquid chromatography with dual‐wavelength ultraviolet detection at 234 and 254 nm has been developed for the determination of underivatized N‐nitrosodiethanolamine in coconut diethanolamide. The correlation coefficient obtained shows that the method is correct.     

Synthesis of nitropyridine‐based π‐conjugated polymers and their chemical properties

π‐Conjugated poly(3‐nitropyridine‐2,5‐diyl) ( PPy‐3‐NO₂ ), poly(3,3′‐dinitro‐2,2′‐bipyridine‐5,5′‐diyl) ( PBpy‐3,3′‐diNO₂ ), and a poly(arylene ethynylene) type polymer consisting of a 3,3′‐dinitro‐2,2′‐bipyridine unit ( PAE‐1 ) were synthesized by Cu‐promoted Ullmann coupling reaction and Pd‐catalyzed coupling reaction. PPy‐3‐NO₂ and PAE‐1 were soluble in organic solvents such as DMSO, DMF, and chloroform, and gel permeation chromatography analysis showed a number average molecular weight (M_n) of 9,300 and 12,300, respectively. PPy‐3‐NO₂ gave intrinsic viscosity, [η], of 0.53 dL g^?1 in DMF. PBpy‐3,3′‐diNO₂ had somewhat lower solubility. The polymers exhibited a UV–vis peak at about 430 nm. PPy‐NO₂ received electrochemical reduction at ?1.5 V versus Ag⁺/Ag in acetonitrile, and gave an electrochemical redox cycle in a range from 0 to ?1.1 V versus Ag⁺/Ag in an aqueous solution. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 1763–1767, 2006