• Journal of the Korean Chemical Society
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• v.9 no.4
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• pp.174-178
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• 1965

p-Phenylenediamine dihydrobromide and p-phenylenediamine dihydrochloride are found to be isomorphous. p-Phenylenediamine dihydrobromide is triclinic with lattice parameters, $a=4.52{\pm}0.02{\AA}\;b=6.13{\pm}0.02{\AA},c=8.88{\pm}0.03{\AA},\;{\alpha}=111{\pm}1^{\circ},\;{\beta}=97{\pm}1^{\circ},\;{\gamma}=101{\pm}1^{\circ}.$ It belongs to space group $P\bar{1}$, and there is one molecule in the unit cell. The crystal structure is determined according to the method of Fourier synthesis from the electron density projections in three principal crystallographic axes. The crystal structure, thus determined is refined by the method of two-dimensional difference Fourier synthesis.

• 월간산업보건
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• s.300
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• pp.4-7
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• 2013

m-Phenylenediamine의 직업적 노출기준 TLV-TWA $0.1mg/m^3$은 간 손상을 최소화하기 위하여 권고하였다. 또한 이 수준은 피부 자극이나 피부염을 예방하기 위한 기준이다. 흰쥐와 생쥐에게 m-phenylenediamine을 처치한 후의 발암성이 음성적이거나 명확하지 않은 결과로 A4(Not Classifiable as a Human Carcinogen, 사람에게 발암성으로 분류되지 않음)로 권고하였다 m-Phenylenediamine을 생산하는 근로자들에서 피부 알레르기반응이 있었다는 제한적인 자료도 있었지만 피부(Skin)와 감작제(SEN)의 경고주석 그리고 TLV-STEL을 권고하기에는 유용한 자료가 충분하지는 않다.

• Journal of Life Science
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• v.13 no.6
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• pp.836-842
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• 2003

1-(2-Aminophenyl)pyrrole 5 was synthesized by using 1,2-phenylenediamine with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid. 1-(3-Aminophenyl)pyrrole 7 and 1,3-dipyrrolylbenzene 8 were obtained by using 1,3-phenylene-diamine with 2,5-dimethoxytetrahydrofuran in glacial acetic acid. 1,4-Dipyrrolylbenzene 10 was synthesized by using 1,4-phenylenediamine with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid. Aminophenylpyrroles 5, 7 and dipyrrolylbenzenes 8, 10 were respectively synthesized by treatment of 1,2-phenylenediamine, 1,3-phenylenediamine, 1,4-phenylene-diamine and 2,5-dimethoxytetrahydrofuran in (1) no solvent or (2) acrylic acid or (3) silica gel or (4) acrylic acid and silica gel or (5) silica gel and glacial acetic acid instead of glacial acetic acid. The best yield for dipyrrolylbenzene 10 was obtained when silica gel and glacial acetic acid was used. 9-Phenyl-carbazole 11 was synthesized by treatment of 1-phenylpyrrole with 2,5-dimethoxy-tetrahydrofuran in glacial acetic acid.

• Elastomers and Composites
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• v.34 no.2
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• pp.147-155
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• 1999

Waxes compounded into rubber migrate to the surface and form a protection film on the rubber surface. In general, antiozonants were used with wax to protect ozonation of rubber. Influence of wax barrier formed on the surface of a rubber vulcanizate on migration of antiozonants was studied using natural rubber (NR) vulcanizates containing various type waxes. IPPD (N-isopropyl-N'-phenyl-p-phenylenediamine), HPPD (N-l,3-dimethylbutyl-N'-phenyl-p-phenylenediamine), SBPPD (N,N'-di(sec-butyl)-p-phenylenediamine), and DMPPD (N,N'-di(1,4-dimethylpentyl)-p-phenylenediamine) were employed as antiozonants. Migration experiments were performed at constant temperatures of 60 and $80^{\circ}C$ for 10, 20, 30 days using a convection oven. The migration rates of the antiozonants in the vulcanizate without wax are faster than those in the vulcanizates containing waxes. The antiozonants migrate slower in the vulcanizate containing wax with a high molecular weight distribution than in the vulcanizate with a low one. The migration rates of DMPPD and SBPPD are faster than those of HPPD and IPPD.

• Journal of the Korean Chemical Society
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• v.21 no.5
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• pp.320-329
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• 1977

p-Phenylenediamine dihydroperchlorate, $C_6H_4N_2H_4{\cdot}2HC1O_4$, crystallizes in space group $P\={1}$ with $a=4.79{\pm}0.02,\;b=9.03{\pm}0.02,\;c=7.12{\pm}0.03{\AA},\;{\alpha}=109.4{\pm}0.2,\;{\beta}=79.6{\pm}0.2,\;r=104.6{\pm}0.2^{\circ},\;Z=1$. The structure has been solved by the Patterson and Fourier methods. The refinement by block-diagonal least-squares cycles gives R = 0.13 for 387 observed reflexions collected on equi-inclination Weissenberg photographs with CuK${\alpha}$ radiation. There are two different types of five hydrogen bonds. The first type consists of one trifurcated N${\cdot}{\cdot}{\cdot}$O hydrogen bond and the second of two normal N${\cdot}{\cdot}{\cdot}$O hydrogen bonds, both of which exist between the amino group and the perchlorate, groups. A p-phenylenediamine group is approximately planar within an experimental error and bonded to twelve perchlorates: ten perchlorates forming hydrogen bonds and two being contacted with the van der Waals forces. A perchlorate group is surrounded by six p-phenylenediamines and four perchlorates; among the six p-phenylenediamines, five of them are hydrogen-bonded, and the rest contacted with the van der Waals force.ce anaysis of our samples and investigated the variarions in the values of parameters obtained through fitting the theoretical impedance to the experimental impedance. The characters of the dielectric constant and the impedance showed abnormal variations for the 0.2 at K-doped NSBN ceramics, which we were able to interpret in terms of the variations in the number A-site vacancies with the K doping ratio. From these results, A-site vacancies are thought to be space charges that influence the ferroelectric properties of NSBN ceramics.

• Journal of the Korean Chemical Society
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• v.9 no.3
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• pp.142-147
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• 1965

The crystal structure of p-phenylenediamine dihydrochloride has been determined from X-ray oscillation and Weissenberg photographs. The crystal is triclinic, space group $C_i1-P{\bar\1},$ with cell dimensions $a = 4.38{\pm}0.02, b = 5.90{\pm}0.02, c = 8.76{\pm}0.03 {\AA}, {\alpha} = 110{\AA}1, {\beta} = 96{\pm}1\; and\; {\gamma} = 101{\pm}1^{\circ}.$ There is one molecule in the unit cell. The atomic coordinates were found by means of two-dimensional Fourier projection and ($F_o-F_c$) projection along the a, b and c axes. The structure of p-phenylenediamine dihydrochloride is discussed in relation to the structures of hexamethylenediamine dihydrochloride, hexamethylenediamine dihydroiodide and ethylenediamine dihydrochloride.

• Polymer(Korea)
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• v.26 no.3
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• pp.375-380
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• 2002

Diamines (p-phenylenediamine , m-phenylenediamine , and n-hexamethylenediamine) were intercalated into sodium montmorillonite for the further reaction with the anhydride end groups of polyamic acid. The anhydride terminated polyamic acid was synthesized using a mole ratio of 4,4'-oxydianilline : 1,2,4,5-benzene tetracarboxylic dianhydride = 1.50 : 1.53. The modified montmorillonite was reacted with polyamic acid terminated with anhydride group in N-methyl-2-pyrrolidone (polyamic acid/clay nanocomposite). After imidization, thin films of the polyimide/clay nanocomposite were prepared. From the results of XRD and TEM, we found that mono layered silicates were dispersed in polyimide matrix and those resultants were exfoliated nanocomposites. Mechanical properties of exfoliated polyimide nanocomposite were better than both those of pure polyimide and those of intercalated polyimide nanocomposite.

• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.389-393
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• 2002

• Polymer(Korea)
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• v.25 no.6
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• pp.796-802
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• 2001

Novel monomer for polybenzimidazole was prepared and polymerized via aromatic nucleophilic substitution reaction. Thus, N-(4-fluorobenzoyl)-4-methoxy-N'-naphthyl-1,2-phenylenediamine was synthesized from the reaction of 4-methoxy-N-naphthyl-1,2-phenylenediamine and 4-fluorobenzoyl chloride. N-(4-fluorobenzoyl)-4-methoxy-N'-naphthyl-1,2-phenylenediamine was converted to 2-(4-fluorobenzoyl)-5-hydroxy-1-naphthylbenzimidazole by ring closure and demethylation reaction. Polymerization was done in N-cyclohexyl-2-pyrrolidinone (CHP) containing potassium car bonate. The resulting polymer was soluble in N-methyl-2-pyrrolidinone (NMP) and had inherent viscosity of 0.38 dL/g (NMP at $30^{\circ}C$). The glass transition temperature ($T_g$ ) of the polybenzimidazole was $270^{\circ}C$. The thermogravimetric analysis (TGA) thermograms of this polymer showed 5% weight losses at $550^{\circ}C$ in nitrogen and at $540^{\circ}C$ in air.

• Food Science and Preservation
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• v.5 no.4
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• pp.386-391
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• 1998

Lactobacillus plantarum KLAB21 isolated from kimchi has been shown to produce antimutagenic subtance(s) into the culture medium using Salmonella typhimurium TA100 and S. typhimurium TA98 (Rhee and Park, Korean J. Appl. Microbiol.. Biotechnol., 1999, in press). In this study, the effects of culture conditions were investigated to maximize the production of antimutagenic substance(s) against 4-nitro-O-phenylenediamine(NPD) by the strain KLAB21. Glucose(255) as a carbon source and yeast extract or bactopeptone(1%) as a nitrogen source showed the highest production of the antimutagenic substance(s). Optimal initial pH of the culture medium, culture temperature and shaking speed for the antimutagenic substance(s) production were pH 7.0, 37$^{\circ}C$ and 150rpm, respectively. Under the optimal conditions, the antimutagenic activity of L. plantarum KLAB21 culture supernatant against NPD on Salmonella typhimurium TA100 and S. typhimurium TA98 were 73.95% and 59.74%, respectively.