Oxidative Polycondensation Reaction Research Articles

The green synthesis of oligo(azomethine)s based on p-anisidine and o-anisidine: reaction conditions, electrochemical and thermal properties

Schiff bases and their conjugated oligo(azomethine)s have been synthesized via condensation and oxidative polycondensation of o-anisidine (OA) with 2-hydroxy-1-naphthaldehyde (2-HNA) and p-anisidine (PA) with 4-hydroxy benzaldehyde (4-HBA), respectively. The oxidative polycondensation reaction conditions of 1-[(2-methoxyphenylimino)methyl]naphthalen-2-ol (1,2-MPIMN) and 4-[(4-methoxyphenylimino)methyl]phenol (4,4-MPIMP) were studied by oxidants such as air and aqueous solutions of H2O2 and NaOCl in different concentrations in an aqueous alkaline medium between 50 °C and 90 °C at different reaction times. The structures of polymers were confirmed by FT-IR, UV-Vis and 1H-13C-NMR measurements. The molecular weights and surface morphologies of oligomers were determined by size exclusion chromatography (SEC) and scanning electron microscopy (SEM), respectively. Electrochemical and thermal features of compounds were studied using UV-Vis spectroscopies, cycling voltammetry (CV), and TG-DTA. The mass losses values ​​of the 1,2-MPIMN, oligo(1,2-MPIMN), 4,4-MPIMP, and oligo(4,4-MPIMP) were calculated from the thermogravimetric curves as 98.00%, 53.52%, 69.00%, and 58.70%, respectively, at 1000 °C. The HOMO, LUMO levels, electrochemical (E’ g ), and optical band gap energies (Eg ) values of the compounds were calculated from CV and UV-Vis data. The E’ g values of 1,2-MPIMN, oligo(1,2-MPIMN), 4,4-MPIMP, and oligo(4,4-MPIMP) were found to be 2.64, 1.54, 2.31, and 2.16 eV, respectively. The electrical properties of monomers and oligomers were determined at room temperature.

Synthesis, characterization and investigation of fluorescent Sn2+ probe potential of pyrene-derived monomer and its oligo(azomethine) compound

A monomer (2-methoxy-6-((pyren-1-yl-imino)methyl)phenol, VP) was synthesized by the Schiff base reaction of o-vanillin (VA) and 1-aminopyrene (AP), and an oligomer (oligo-2-methoxy-6-((pyren-1-yl-imino)methyl)phenol, OVP) was synthesized from this monomer via oxidative polycondensation reaction. The structural characterization of the obtained monomer and oligomer by FT-IR, 1H NMR and 13C NMR; electrochemical properties with cyclic voltammetry (CV); optical properties with UV–Vis and photoluminescence (PL) spectroscopy; thermal stability with thermogravimetric analysis (TGA); and the molecular weight of the oligomer were determined by gel permeation chromatography (GPC). From the fluorescence titration, VP was found to be sensitive to Sn2+ out of a range of metal ions. When the VP solution, to which 1 equivalent amount of Sn2+ was added, was excited with 320 nm light, it was observed that it emits bright blue color at 445 nm. It was found that VP, whose limit of detection (LOD) was calculated as 4.24 nM for Sn2+, had a sensitive and selective fluorescence sensor potential. In addition, it was found that the obtained oligo[2-methoxy-6-((pyren-1-yl-imino)methyl)phenol] (OVP) had a molecular mass of 3450 Da and showed fluorescent properties. The maximum emission of the OVP excited with 380 nm light was observed at 443 nm, with green emission.

Synthesis, structure analysis, investigation of conductivity, thermal properties of polyphenol derivatives containing a rhodanine moiety and their Cu(II), VO(IV) complexes

In this study, 5-benzylidenerhodanine derivatives namely 5-(2-hydroxybenzylidene)-2-thioxothiazolidin-4-one (SAR) and 5-((2-hydroxynaphthalen-1-yl)methylene)-2-thioxothiazolidin-4-one (HNAR) used as monomer. The new polymers of SAR and HNAR (PSAR and PHNAR respectively) were synthesized by oxidative polycondensation reaction. The polymers were characterized by elemental, FT-IR, UV–Vis, 1H NMR, 13C NMR, TG-DTA analyses techniques. The molecular weight distribution values of the PSAR and PHNAR were determined by size exclusion chromatography (SEC) analysis. According to the SEC analyses, the number average molecular weight (Mn), weight average molecular weight (Mw) and polydispersity index (PDI) values of PSAR and PHNAR were found to be 5300, 7250 g mol−1 and 1.368; 5750, 7350 g mol−1 and 1.278, respectively. The Cu (II), VO (IV) complexes of PSAR and PHNAR (PSAR-Cu and PSAR-VO) were successfully prepared using Cu (AcO)2xH2O and VOSO4x5H2O hydrate salts. The polymer-metal-complexes were characterized by FT-IR, elemental and TG-DTA analysis techniques. The weight losses of PHNAR, PHNAR-Cu, PHNAR-VO, PSAR, PSAR-Cu and PSAR-VO were found to be 69.50, 58.50, 62.25, 89.05, 74.55 and 61.75% at 1000 °C, respectively. TG analyses were showed to be stable of synthesized polymers against thermal decomposition. Electrical properties of doped polymers, undoped polymers and their complexes were determined. Also, the optical band gaps (Eg) of these complexes were calculated from their absorption edges.

Synthesis of new azo dye polymers based on naphthol by oxidative polycondensation: antimicrobial activity and fastness studies

Azo dye polymers were synthesized by an oxidative polycondensation reaction of naphthol based azo dyes with the oxidants NaOCl in an aqueous alkaline medium. These synthesized azo dye polymers were characterized by UV-Vis, FT-IR, 1H NMR techniques. The surface morphology of the azo dye polymers was understood by Scanning Electronic Microscopic study(SEM). The changes in weight in relation to change in temperature of synthesized compounds the was studied by TGA/DTA analysis. All the novel polymers were characterized to determine molecular weights by gel permeation chromatography(GPC). All of the azo dye monomers and polymers were researched for antibacterial (Corynebacterium xerosis, Bacillus brevis, Bacillus megaterium, Bacillus cereus, Mycobacterium smegmatis, Staphylococcus aureus, Micrococcus luteus Enterococcus faecalis, Acinetobacter baumannii, Pseudomonas aeruginosa, Klebsiella pneumoniae, Escherichia coli, Yersinia enterocolitica) and antifungal (Kluyveromyces fragilis, Saccharomyces cerevisiae, Candida albicans) activities. When results of antibacterial activity of synthesized compounds was compared with standard Ampicillin, Streptomycin Sulfate, Nystatin. it is seen that the azo dye monomers had good antibacterial activity whereas the azo dye polymers did not have as good activity as the monomers. The dyes were examined in respect of their washing, water, sweat (acid and base) and frictional (dry and wet) fastness. From the results, It was found that The fastness properties of the azo dye monomers are better than the polymers. Because the bonding ability to the fabric in the monomers is better than the long chain polymers having a high molecular weight.

Synthesis, Electrochemical and Fluorescence Properties of Poly(azomethine-naphthalene)s

In this study, novel types of poly(azomethine-naphthalene)s were synthesized containing naphthalene unit along the main chain in two steps. In the first step, symmetrical Schiff base diols that contain naphthalene unit in center and in the second step, poly(azomethine-naphthalene)s expanding with C–C coupling were obtained by elimination and oxidative polycondensation reactions, respectively. These purely synthesized compounds were characterized by UV–Vis, FT-IR, $$^{1}\hbox {H-NMR}$$ and $$^{13}\hbox {C-NMR}$$ analyses, and also their electrochemical, thermal, photonic and surface properties were illuminated by cyclic voltammetry (CV), thermogravimetric analysis, differential thermal analysis, differential scanning calorimetry, photoluminescence and scanning electron microscopy analysis techniques. According to TG analysis, char % amounts of P-2HBAN, P-2HNAN, P-4HBAN and P-3H4MBAN were found to be 9.3, 18.0, 66.6 and 47.1, respectively, at $$1000\, ^{\circ }\hbox {C}$$ . Also, these compounds have glass transition temperature $$({T}_{\mathrm{g}})$$ higher than $$127\,^{\circ }\hbox {C}$$ and onset temperature higher than $$153 \,^{\circ }\hbox {C}$$ . For this reason, they are useful for the production of thermal-resistant materials. In addition, electrochemical and fluorescence properties of all the compounds were examined by CV and fluorescence spectrophotometer measurements, respectively.

Synthesis, characterisation, solvatochromic behaviour and thermal decomposition kinetics of novel polyazo dyes containing amide group and their transition metal complexes

The present study describes the synthesis of two new azo dyes which possess azo and amide group by general diazo-coupling reaction of 2-Amino-4-chlorophenyl phenyl and 8-Amino-2-naphthol with Naftol AS used as coupling compound. Additionally, the homopolymers of the obtained azo dyes were synthesised by oxidative polycondensation reaction. Then, Ag+1 and Cu+2 metal complexes of both monomer and polymer were synthesised. The molecular structures of the newly synthesised compounds were confirmed by different spectroscopic techniques such as 1H NMR, 13C NMR, FT-IR, UV–vis, SEM, TGA, and powder XRD techniques. The X-ray diffraction pattern of the synthesised compounds indicated that the compounds had amorphous and crystalline characters. The solvatochromic behaviours of all compounds were evaluated at room temperature in seven solvents having different polarities. The obtained results showed that the absorption peaks of polymers are red shifted compared to monomers. The thermodynamic parameters of all compounds were calculated from TGA curve employing the Coast–Redfern and Horowitz–Metzger methods.

Synthesis and Characterization A Novel Thermally Stable Schiff Base Oligomer: Investigation of Conductivity Properties

This paper presents design of a novel Schiff base, 2,2'-{[1,2-di(pyridin-2-yl)ethane-1,2-diylidene]bis(azanylylidene)}diphenol (2,2-DBD), and its oligophenol, Oligo-(2,2'-{[1,2-di(pyridin-2-yl)ethane-1,2-diylidene]bis(azanylylidene)}diphenol) O(2,2-DBD), synthesized with NaOCl and O2 oxidants in aqueous alkaline medium by oxidative polycondensation reaction. The effects of oxidant type, polymerization temperature and time on oligomer yield were determined. Characterization of the structures of the synthesized (2,2-DBD) and O(2,2-DBD) were done by UV-Vis, FTIR and 1HNMR techniques. Also, thermal degradations of the monomer and oligomer were investigated TG-DTG analysis and it was determined that the oligomer thermally stable up to 1200 ˚C. Additionally, electrical conductivity of the oligomer was improved by doping with iodine at 20 ˚C and the conductivity of the oligomer reached to 9x10-4 S/cm by increasing 107 at the end of the 48 h doping time fold according to its undoped form.

Synthesis, Characterization and Optimum Reaction Conditions of Oligo-N-Salicylidenephenylhydrazone via Oxidative Polymerization

The oxidative polycondensation reaction conditions and optimum parameters of N-salicylidenephenylhydrazone (SPH) were determined using air, H2O2 and NaOCl as oxidants at a temperature range between 50 °C and 95 °C in an aqueous alkaline medium. The molecular structures of the obtained monomer and oligomer were confirmed by FT-IR, UV-Vis, 1H-NMR and elemental analyses. The characterization was fulfilled by TG-DTA, size exclusion chromatography (SEC) and solubility tests. The conversion of N-salicylidenephenylhydrazone into oligomer was performed using air, H2O2 and NaOCl as oxidants in an aqueous alkaline medium. According to SEC analysis, the number-average molecular weight (Mn), weight-average molecular weight (Mw) and polydispersity index (PDI) values of oligo-N-salicylidenephenylhydrazone (OSPH) obtained using NaOCl oxidant were found to be 1436 g mol-1, 1631 g mol-1 and 1.14, respectively. The conversion yield of N-salicylidenephenylhydrazone into oligo-N-salicylidenephenylhydrazone was 100% at optimum reaction conditions such as [SPH]0 = [KOH]0 = [H2O2]0 =0.06, mol/L and at 90 °C for 10 h. Also, according to TG-DTA analysis, oligo-N-salicylidenephenylhydrazone was shown to be thermally stable and resistant to thermo-oxidative decomposition. The weight loss of OSPH was found to be 20, 50 and 92.56% at 275°, 597° and 1000 °C, respectively.

Reaction conditions, photophysical, electrochemical, conductivity, and thermal properties of polyazomethines

In this paper, a series of Schiff bases and their polyazomethine derivatives were synthesized via condensation and oxidative polycondensation reactions of 4-aminophenol with 4-isopropylbenzaldehyde or 4-t-butylbenzaldehyde. Polymerization reaction conditions for polymerization yield of polyazomethines were investigated by changing some experimental parameters such as time and temperature using different oxidants like alkaline NaOCl (30%) and air. The structural characterizations of Schiff bases and polymers were performed using FT-IR, 1H NMR, 13C NMR and SEC techniques. Photophysical properties were studied UV-vis and photoluminescence spectroscopies. Electrochemical properties were also investigated cyclic voltammetry (CV) and electrochemical band gaps determined in the range 1.73 to 2.63 eV. Thermal properties of the compounds were investigated using TG-DTA and DSC techniques and char residue at 1000 oC determined between 3-6% and 39-34% for Schiff bases and polyazomethines, respectively. Moreover, conductivity measurements were done using four-point probe technique at both doped with iodine vapor and un-doped state.

Synthesis, characterization and molecular weight monitoring of a novel Schiff base polymer containing phenol group: Thermal stability, conductivity and antimicrobial properties

A novel Schiff base polymer containing phenol group, Poly(3-[[4-(dimethylamino)benzylidene]amino]phenol) P(3-DBAP), was prepared by oxidative polycondensation reaction of 3-[[4-(dimethylamino)benzylidene]amino]phenol (3-DBAP) using NaOCl, H2O2, O2 oxidants in aqueous alkaline medium. Yield and molecular weight distribution of P(3-DBAP) were monitored depending on oxidant types and concentration, monomer concentration and as well as polymerization temperature and time. UV–Vis, FTIR and 1HNMR techniques were used to identify the structures of Schiff base monomer and polymer. Thermal behavior of P(3-DBAP), which was determined to be thermally stable up to 1200 °C via TG-DTG techniques, was illuminated by Thermo-IR spectra recorded in the temperature range of 25–800 °C. It was determined that the electrical conductivity value of the P(3-DBAP) increased 108 fold after doped with iodine for 24 h at 60 °C according to undoped form and it was measured 4.6 × 10−4 S/cm. Also, antibacterial and antifungal activities of the monomer and polymer were assayed against Sarcina lutea, Enterobacter aerogenes, Escherichia coli, Enterococcus Feacalis, Klebsiella pneumoniae, Bacillus subtilis bacteria, and Candida albicans, Saccharomyces cerevisiae fungi.

Synthesis, Characterization, Electrical Conductivity and Fluorescence Properties of Polyimine Bearing Phenylacetylene Units.

In this study, a Schiff base was synthesized by the condensation reaction of 4-bromobenzaldehyde and 4-aminophenol. Then, phenylacetylene substituted Schiff base monomer (IPA) was obtained by HBr elimination reaction of IPA with phenylacetylene through Sonogashira reaction. IPA was polymerized via chemical oxidative polycondensation reaction. FT-IR and NMR measurements were used for the structural analyses of the synthesized substances. Fluorescence and UV-Vis analyses were carried out for optical characterization. Electrochemical characteristics, electrical conductivities and thermal properties were determined using cyclic voltammetry (CV), four-point probe conductometer, TG-DTA and DSC methods. The main purpose of the present study was to investigate the effects of phenylacetylene bearing units on the properties of conjugated aromatic polyimines. The spectral analysis signified a green light emission behavior when irradiated at different wavelengths. Combined with fluorescent behavior and good thermal stability, the electrical conductivity was found to be very crucial for π-conjugated polymer.

Synthesis, characterization, conductivity and antimicrobial study of a novel thermally stable polyphenol containing azomethine group

Poly(4-[[(4-methylphenyl)methylene]amino]phenol) (P(4-MMAP)), which is a Schiff base polymer, was synthesized by an oxidative polycondensation reaction of 4-[[(4-methylphenyl)methylene]amino]phenol (4-MMAP) with the oxidants NaOCl, H2O2 and O2 in an aqueous alkaline medium. The polymerizations were carried out at various temperatures and times, and the highest polymer yield could be obtained when using 37% with NaOCl oxidant. The structures of the monomer and polymer were characterized by UV–Vis, FTIR 1H NMR and X-ray diffraction techniques. The thermal behaviors of the monomer and polymer were identified by the TG and DTG techniques. The thermal degradation of the polymer which was observed thermally stable up to 1000 °C, was also supported by the Thermo-IR spectra recorded in the temperature range of 25–800 °C. The number average molecular weight (Mn), weight average molecular weight (Mw) and polydispersity index (PDI) of the polymer were found to be 16682, 57796 g/mol and 3.4, respectively. The highest electrical conductivity value of P(4-MMAP) doped with iodine vapor at different temperatures and times was measured to be 7.8 × 10−5 Scm−1 after doping for 48 h at 60 °C. The antibacterial and antifungal activities of 4-MMAP and P(4-MMAP) were also assayed against the bacteria Sarcina lutea, Enterobacter aerogenes, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Bacillus subtilis and the fungi Candida albicans, Saccharomyces cerevisiae, respectively.

Electrical and photoelectrical behaviour of heterojunctions based on novel oligomeric metal complexes

Naringenin‐based Schiff base ligands with 4‐aminobenzoic hydrazide were obtained as a unilateral form (L1). The ligand was oligomerized by oxidative polycondensation reaction with NaOCl as an oxidant in an aqueous alkaline medium at 90 °C to form a functional oligomer (L2), and its transition metal complexes such as those with Cu(II), Ni(II) and Zn(II) were prepared. The monomer and the oligomeric compounds were characterized using various techniques. Optical and electrical properties of the complexes were also investigated. All compounds showed indirect band gaps and they can be accepted as being in the semiconductor class. Organic–inorganic hybrid devices were obtained using n‐Si inorganic semiconductor and the complexes. The characteristic parameters of the devices were determined using current–voltage (I–V) and capacitance–voltage measurements in the dark. Photoelectrical properties of the devices were investigated using I–V measurements under a solar simulator with an AM1.5 global filter. Copyright © 2015 John Wiley & Sons, Ltd.

Novel Multicolor Schiff Base Polymers Prepared via Oxidative Polycondensation.

A series of diimine Schiff bases and their polymers were synthesized via the oxidative polycondensation reaction. The structures of the compounds were confirmed by (1)H-NMR, (13)C-NMR, FT-IR and UV-vis spectral measurements. Electrochemical and optical band gap values of synthesized compounds were determined by cyclic voltammetry (CV) and UV-vis measurements, respectively. Fluorescence measurements of the compounds were conducted in various solvents. The effects of solution concentration on the fluorescence spectra were investigated and quantum yield was calculated for the polymer of 5-(diethylamino)-2-(biphenylmethylene) hydrazonomethylphenol (PDEAHP). According to fluorescence measurements, the quantum yield of PDEAHP was found as 16% in DMF solution. Thermal characteristics of polymers were studied by TG-DTA and DSC analyses.

Poly‐2‐[(4‐methylbenzylidene)amino]phenol: Investigation of thermal degradation and antimicrobial properties

ABSTRACTA new polyphenol (poly‐2‐[(4‐methylbenzylidene)amino]phenol) (P(2‐MBAP)) containing an azomethine group was synthesized by oxidative polycondensation reaction of 2‐[(4‐methylbenzylidene)amino]phenol (2‐MBAP) with NaOCl, H2O2, and O2 oxidants in an aqueous alkaline medium. The structures of 2‐MBAP and P(2‐MBAP) were characterized by UV‐vis, FT‐IR, and 1H NMR spectra. While the monomer decomposed completely up to 350°C and 57.2% of the polymer decomposed up to 1000°C. The thermal degradation of P(2‐MBAP) was also supported by the Thermo‐IR spectra recorded in the temperature range of 25–800°C. Electrical conductivity of the polymer was observed to increase 108 fold after doping with I2. Antimicrobial activities of the P(2‐MBAP) and 2‐MBAP against Sarcina lutea, Enterobacter aerogenes, Escherichia coli, Enterococcus feacalis, Klebsiella pneumoniae, Bacillus subtilis, Candida albicans, and Saccharomyces cerevisiae were also investigated. The number average molecular weight (Mn), weight average molecular weight (Mw) and polydispersity index (PDI) of the polymers were determined by gel permeation chromatography (GPC). © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41758.

Synthesis and characterizations of poly(ether)/poly(phenol)s including azomethine coupled benzothiazole side chains: the effect of reaction conditions on the structure, optical, electrochemical, electrical and thermal properties

A new Schiff base, 4-((6-ethoxybenzothiazole-2-ylimino)methyl)benzene-1,2-diol (3,4-HBAEBT) was synthesized by the condensation reaction of 3,4-dihydroxybenzaldehyde (3,4-HBA) and 2-amino-6-ethoxybenzothiazole. The Schiff base, then, was converted to its polymer derivatives by oxidative polycondensation reaction in both organic (P-1) and aqueous alkaline medium (P-2). Spectral observations indicated different structural properties for each polymerization condition. Organic and aqueous alkaline medium produced poly(ether) and poly(phenol) structures, respectively. The obtained polymers were separately studied with respect to optical, electrochemical, electrical and thermal properties. With exception of thermal degradation behaviors, the other investigated properties as well as morphological characteristics of both polymers were considerably different. In the fluorescence measurements a solvatochromic effect was recorded and the emission colors of the polymers could be changed as turquoise-green by solvent change.

Synthesis, characterization, optical, and electrochemical properties of thermal stable novel poly(azomethine-ether)s

In this study, the novel Schiff base monomers were synthesized by condensation reactions. Then, these monomers were converted to poly(azomethine-ether)s by oxidative polycondensation (OP) reactions in an aqueous alkaline medium. The structural characterizations of compounds were carried out by FT-IR, NMR, and size exclusion chromatography (SEC). According to the SEC analysis, the calculated number-average molecular weight (Mn), weight average molecular weight (Mw), and polydispersity index values of P-2 and P-4 were found to be 17,500 g mol−1, 24,400 g mol−1, and 1.39; and 18,700 g mol−1, 25,600 g mol−1, and 1.36, respectively. The HOMO-LUMO energy levels, electrochemical (), and optical (Eg) band gaps of polymers were calculated from cyclic voltammetry (CV) and UV–vis measurements, respectively. CV was used to determine the electrochemical oxidation–reduction characteristics of polymers. Thermal characterizations of compounds were made by using TG-DTA and DSC techniques. According to TG analysis, polymers with higher initial degradation temperatures (Ton) than those of their monomers indicate that the synthesized polyphenols have higher thermal stabilities than their monomer species.

Polysulfone–polyaniline‐type membranes obtained in a steady‐state system: Structural and hydrodynamic characteristics

Structural and hydrodynamic characteristics of polysulfone–polyaniline‐type membranes (Psf‐PANI) are depending on a number of parameters. The present article details the influence upon such membrane of the characteristics of obtaining process, type of monomer used in generating the composite membrane and pH of the solution permeating the membranes (for flow characterization). Membranes were obtained in a steady‐state process, using an inversion phase technique accompanied by an in situ chemical reaction. The composite character of the material is a result of inserting, in the pre‐existing porous polymer structure (polysulfone, Psf) of a second monomer (aniline or substituted anilines, e.g., amino‐benzoic acid, 3ABA) through an oxidative polycondensation reaction. The steady‐state process ensures a constant and reproducible structure of the composite material. As the study shows, from the two types of obtained composite membranes, the one that uses aniline polycondensation on polysulfone substrate presents better performances, compared with the one that uses substituted aniline in polycondensation (Psf‐P3ABA). POLYM. ENG. SCI., 54:1640–1647, 2014. © 2013 Society of Plastics Engineers

Syntheses and characterization of poly(iminophenol)s derived from 4-bromobenzaldehyde: Thermal, optical, electrochemical and fluorescent properties

Schiff base monomers [2-(4-bromobenzylideneamino)phenol and 2-(4-bromobenzylideneamino)-5-methylphenol] were synthesized by the condensation reaction of 4-bromobenzaldehyde with aromatic aminophenols. Then, the monomers were converted to their polyphenol derivatives by oxidative polycondensation reactions (OP) in an aqueous alkaline medium. The structures of the synthesized compounds were characterized by solubility tests, FT-IR, NMR, TG-DTA, DSC and SEC techniques. The HOMO-LUMO energy levels and electrochemical (Eg′) and optical (Eg) band gaps were calculated from cyclic voltammetry (CV) and UV-Vis measurements, respectively. Cyclic voltammetry (CV) was used to determine the electrochemical oxidation-reduction characteristics. Optical properties were investigated by UV-Vis and fluorescence analyses. Solid state electrical conductivities were measured on polymer films by four point probe technique using a Keithley 2400 electrometer. The effects of electron-donating (−CH3) group at p-position of -NH2 group in aminophenol on electrochemical and thermal properties were also discussed. Photoluminescence (PL) properties of the synthesized materials were determined in solution forms using different solvents. Fluorescence measurements were carried out in various concentrated solutions to determine the optimum concentrations to obtain the maximal PL intensities.

Synthesis, characterization of poly-2- (2-hydroxybenzylideneamino)-6-phenyl-4,5,6, 7-tetrahydrobenzo[b ]thiophene-3-carbonitrile: Investigation of antibacterial activity and optical properties

The oxidative polycondensation reaction conditions of 2-(2-hydroxybenzylideneamino)-6-phenyl-4,5,6,7-tetrahydrobenzo[b]thiophene-3-carbonitrile were examined. The magnitude of the reflectance of the polymer decreases sharply with increasing of wavelength up to 524 nm, then reflectance of the polymer increases slowly with increasing of wavelength. The refractive index values of the polymer vary from 1.474 to 2.350. The Ep and Ed values of the polymer were found to be 4.56 and 7.068 eV, respectively. Absorption coefficient K of the polymer is of the order 817.062–1434.77 m−1. Angle values of incidence and refraction of the polymer vary from 57.36 to 66.95° and from 23.05 to 32.65°, respectively. The film-phase thickness of the polymer increases with increasing photon energy. The thickness, d, of the polymer was of the order 439.3–4184.7 Å for 190 and 1100 nm, respectively. The real part of dielectric constant of the polymer decreases slowly with increasing of frequency up to about 600 THz, then the real part of dielectric constant of the polymer increases sharply with increasing of frequency. The real and imaginary parts of dielectric constant of the polymer vary from 2.17 to 5.52 and from 5.81 × 10−5 to 3.58 × 10−4, respectively. Finally, polymer was tested for antibacterial activities against some bacteria. POLYM. ENG. SCI., 2012. © 2012 Society of Plastics Engineers