• Advances in materials Research
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• v.3 no.2
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• pp.117-128
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• 2014

Processable conducting polyaniline derivative with free amine functional groups was successfully synthesized from the monomer o-phenylenediamine in aqueous hydrochloric acid medium using ammonium persulfate as an oxidative initiator. The synthesized poly(o-phenylenediamine) (PoPD) in critical condition was found to be completely soluble in common organic solvents like dimethyl sulfoxide, N,N-dimethyl formamide etc. From the intrinsic viscosity measurement, the optimum condition for the polymerization was established. The polymer was characterized by ultraviolet visible spectroscopy, Fourier transform infrared spectroscopy, proton magnetic resonance spectroscopy ($^1HNMR$) and thermogravimetric (TGA) analyses. The weight average molecular weights of the synthesized polymers were determined by the dynamic light scattering (DLS) method. From the spectroscopic analysis the structure was found to resemble that of polyaniline derivative with free amine functional groups attached to ortho/meta position in the phenyl ring. However, very little ladder unit was also present with in the polymer chain. The moderate thermal stability of the synthesized polymer could be found from the TGA analysis. The average DC conductivity of $2.8{\times}10^{-4}S/cm$ was observed for the synthesized polymer pellet after doping with hydrochloric acid.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.305-305
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• 2012

The organic-inorganic hybrid polymer thin films were deposited using the gas phase method which known as molecular layer deposition (MLD). Titaniumchloride (TiCl4) and 1,4-phenylenediamine (PD) were used as monomers to deposit hybrid polymer. Self-terminating nature of TiCl4 and PD reaction were demonstrated by growth rate saturation versus precursors dosing time. Infrared spectroscopic and X-ray photoelectron spectroscopy were employed to determine the chemical composition and state of hybrid polymer thin films. Layer by layer growth was showed by increasing UV-VIS absorption peak of hybrid polymer thin films.

• Journal of the Korean Chemical Society
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• v.54 no.5
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• pp.579-581
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• 2010

Solid silica supported ferric chloride ($SiO_2-FeCl_3$) catalyzed one-step synthesis of various benzimidazoles from o-phenylenediamine and aldehydes using $H_2O_2$ as the oxidant. The salient features of this method are simple and convenient procedure, easy purification and shorter reaction times.

• Bulletin of the Korean Chemical Society
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• v.16 no.5
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• pp.392-397
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• 1995

o-Phenylenediamine (o-PD) was electropolymerized on glassy carbon electrodes under a potential cycling condition. The resulting polymer films mediated electrons for the reduction of molecular oxygen at pH=1.0. It was found from the RDE, RRDE, and cyclic voltammetry experiments that the modified electrodes reduce oxygen to hydrogen peroxide at about 300 mV lower potential than the bare glassy carbon electrode. The polymer film consisted of more than two components. Among those, only one component was active in oxygen reduction, which was formed mainly in the earlier stage of the electropolymerization. 2,3-Diaminophenazine, a cyclic dimer of o-PD, was also active in the oxygen reduction reaction, from which it was suggested that the active polymeric component has a structural unit similar to the cyclic dimer. Finally, the electropolymerization mechanism for the formation of the active and inactive components has been proposed.

• YAKHAK HOEJI
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• v.33 no.5
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• pp.273-279
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• 1989

2,3-Dichloro-1,4-naphthoquinone was reacted with o-fluoroaniline, p-sulfadiazine, p-acetoanline, N,N-dimethyl-1,4-phenylenediamine as a nucleophilic substitution to form 2-chloro-3-(N-arylamino)-1,4-naphthoquinones (1.-6.) in good yield. 2,3-Dibromo-1,4-naphthoquinone was also reacted with o-fluoroaniline, m-aminobenzoic acid, m-chloroaniline, morpholine, p-acetoaniline, N,N-dimethyl-1,4-phenylenediamine as a nucleophilic substitution to give 2-bromo-3-(N-arylamino)-1,4-naphthoquinones (7.-12.). These new compounds are expected to have a biological activities such as anticoagulant, cytotoxic.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1280-1282
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• 2008

• Journal of the Korean Chemical Society
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• v.26 no.4
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• pp.250-252
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• 1982

• Elastomers and Composites
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• v.34 no.4
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• pp.341-349
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• 1999

In this study, heat and crack resistance of natural rubber (NR) compounds was evaluated. To prevent the effects of the crosslinking system, a conventional vulcanization system was selected, where the accelerator/sulfur ratio was fixed to 0.25. Vulcanizates containing phenylenediamine showed high tensile strength and tear strength compared to other vulcanizates because phenylenediamine can cause additional crosslinking and high dispersion In the vulcanizates. In the pure shear test, vulcanizates containing phenylenediamine showed an excellent tearing energy which was due to the irregular crack path, and showed excellent heat and crack resistance which was also due to the good dispersity of antioxidant and additional crosslinks in the rubbber vulcanizates.

• Korean Journal of Food Science and Technology
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• v.19 no.6
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• pp.506-514
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• 1987

Peroxidase was purified to a homogeneous state from Castanea Semen by ammonium sulfate precipitation, DEAE-cellulose column chromatography, gel filtration on sephadex G-100 and HPLC, and the purification fold was 65.3. The molecular weight of the enzyme was estimated to be about 35,000 by HPLC. In properties of the enzyme which was purified up to sephadex G-100 column chromatography, the optimum pH and temperature were 5.0 and $50^{\circ}C$, respectively. By heating the enzyme at $80^{\circ}C$ for 1.73 min., the enzyme activity was decreased to 10%. The enzyme was active toward aromatic amines such as o-phenylenediamine and p-phenylendiamine. Kinetic studies indicated a Km of 2.6mM for o-phenylenediamine at an optimal hydrogen-peroxide concentration and a Km of 10mM for hydrogenperoxide at an optimal o-phenylenediamine concentration. Among the reagents tested, L-ascorbic acid and sodium L-ascorbate inhibited significantly the enzyme, while $Ca^{++}$ and $Ba^{++}$ activated the enzyme at the concentration of 1mM and 5mM.

• Biomedical Science Letters
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• v.9 no.2
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• pp.75-84
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• 2003

To evaluate the influence of hepatic oxygen free radical systems on liver injury by topical p-phenylenediamine (PPD) application on rat skin, PPD (25 mg/16.5 $\textrm{cm}^2$) was topically applied to the abdominal region 5 times every other day and sacrificed. By PPD treatment, increasing rate of liver weight/body weight (%), serum activities of alanine aminotransferase and aspartate aminotransferase and decreasing rate of microsomal glucose-6-phosphatase activity were higher in the rats fed tungstate supplemented diet than those fed a standard diet. These findings indicate that group fed tungstate supplemented diet have more severe liver injury compared with group fed standard diet on topical PPD application. However, the activities of oxygen free radical generating enzymes such as xanthine oxidase (XO) and cytochrome P450 dependent aniline hydroxylase and those of oxygen free radical scavenging enzymes were not found to be different between these two animal groups. In the present study, a novel monitoring method to detect the generating of oxygen free radicals in liver extract was devised. Throughout this method, the oxidized PPD produced by oxygen free radicals was determined colorimetrically. The increasing rate of PPD oxidation by liver homogenate was higher in tungstate fed animals than in standard diet fed ones. Among the fractionations of liver extract, the mitochondrial and postmitochondrial fractions in the liver extract of tungstate fed animals led to a higher availability of PPD oxidation by PPD treatment compared with standard diet fed ones. In conclusion, these results suggest that an enhanced liver injury in tungstate fed animals treated with PPD may be due to oxygen free radicals produced in other systems except oxygen free radicals generating from cytosolic XO system. Especially, oxidative availability by PPD can be used for oxygen free radical detection in some tissue.