• Title/Summary/Keyword: Anhydride

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Determination of Reactivities by Molecular Orbital Theory Part IV. Application of IMO Method to some Thermal Diels-Alder Reactions

  • Chang Hoon Park;Ikchoon Lee
    • Journal of the Korean Chemical Society
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    • v.16 no.3
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    • pp.142-148
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    • 1972
  • The intermolecular orbital theory was applied to the Diels-Alder reaction of naphthalene, phenanthrene and 1,2-benzanthracene with maleic anhydride. The expected positions of thermal addition in the alternant bydrocarbons were in agreement with experiment. It was also possible to explain the relative proportions of two isomeric adducts with the calculated stabilization energies. Comparison of the results with paralocalization energies of Brown gave agood linear correlation.

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Influence of Maleic Anhydride Grafted onto Polyethylene on Pyrolysis Behaviors

  • Chung, Yu Yeon;Choi, Sung-Seen
    • Elastomers and Composites
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    • v.51 no.3
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    • pp.233-239
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    • 2016
  • Polyethylene (PE) and maleic anhydride-grafted PE (PE-g-MAH) were pyrolyzed, and their pyrolysis products were analyzed using gas chromatography/mass spectrometry (GC/MS) to investigate the influence of MAH grafted onto PE on pyrolysis behaviors. Major pyrolysis products of PE and PE-g-MAH were n-alkanes, 1-alkenes, ${\alpha},{\omega}$-alkadienes, and aromatic compounds. 1-Alkenes were more formed than n-alkanes, ${\alpha},{\omega}$-alkadienes, and aromatic compounds. Butadiene was more produced from PE than PE-g-MAH, whereas toluene and ethyl benzene were more generated from PE-g-MAH than PE. Difference in the pyrolysis behaviors between PE and PE-g-MAH were explained by initial decomposition of MAH moiety.

Measurement of Degree of Hydrolysis of a PA66/GF Composite using a py-GC/MS analysis

  • Lee, Jong-Young;Kim, Kwang-Jea
    • Elastomers and Composites
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    • v.52 no.1
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    • pp.59-68
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    • 2017
  • The effect on the hydrolysis resistance properties by the addition of maleic anhydride grafted EMDM (MA-g-EPDM) and PP (MA-g-PP) to a PA66/GF composite was investigated with respect to the mechanical properties, thermal properties, and morphology. The degree of hydrolysis of the PA66/GF composite was measured using py-GC/MS analysis. When compared to the PA66/GFcomposite in MEG/water solution, the composites where MA-g-EPDM and MA-g-PP were added to PA66/GF showed a higher degree of hydrolysis resistance, impact strength, and thermal properties, whereas their tensile strength, tensile modulus, flexural strength and flexural modulus decreased. As immersion time in the solution increases, the rate of tensile strength drop of the MA-g-PP added composite appeared lower than that of the PA66/MA-g-EPDM/GF and PA66/GF composites. The py-GC/MS analysis confirmed the formation of PA66 hydrolysis reaction by products such as carboxylic acid and alkylamine with increasing immersion time.

Acylation of Wool Keratin with Dibasic Acid Anhydrides - on reaction mechanism - (2염기산 무수물에 의한 양모섬유의 아실화(I) - 반응메카니즘을 중심으로 -)

  • 신은주;박찬헌;최석철
    • Textile Coloration and Finishing
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    • v.7 no.1
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    • pp.65-71
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    • 1995
  • Wool yarns were treated in dimethylformamide solutions containing various concentrations of three dibasic acid anhydrides : succinic, itaconic, and phthalic anhydrides in various conditions. The structural aspects of these dibasic acid anhydrides are different : the succinic, itaconic, and phthalic acid anhydrides have saturated aliphatic etylene, unsaturated aliphatic vinyl and aromatic phenyl groups, respectively. The reaction mechanism of the acylation of wool keratin and some resction conditions were invastigated. And the results are as follows. 1. The N-acylation and formation of free carboxyl group were dominant rather than the O-acylation cross-linked on the side chain of polypeptide. The acylation of wool keratin is easier than that of silk fibroin. 2. The higher molecular weight, steric hinderance and resonance caused lower acylating reactivity. By the determination of acyl contents for acylated keratin, it was rerealed that the degree of acylation was succinic acid anhydride > itaconic acid anhhydride > phthalic acid anhydride.

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Cure Kinetics for the Acid Anhydride-cured Epoxy System Using a Near-infrared Reflection Spectroscopy (근적외선 분광분석을 통한 산무수물경화 에폭시 시스템의 경화 동력학)

  • 곽근호;박수진;이재락
    • Polymer(Korea)
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    • v.24 no.1
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    • pp.65-71
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    • 2000
  • The latent properties and cure kinetics of an acid anhydride-cured epoxy resin have been investigated by a near-infrared (NIR) reflection spectroscopy. The assignments of the latent properties and cure behaviors were performed by the measurements of the NIR reflectance for epoxide and hydroxyl groups at different temperatures. A comprehensive analysis of the origin, location, and shifts during reaction of all major NIR absorption peaks in the spectral range from 4000 to 7100 $cm^{-1}$ / was provided. The extent of reaction was determined from NIR absorption band at the 4530 $cm^{-1}$ / depending on epoxide concentration and cure temperature.

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Physicochemical Properties of Octenylsuccinated Corn Starch (옥테닐호박산나트륨 전분의 이화학적 특성)

  • 정만곤;임번삼
    • Journal of Food Hygiene and Safety
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    • v.14 no.1
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    • pp.84-89
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    • 1999
  • Octenylscuccinated corn starches prepared by reaction of corn starch with 1-octenylsuccinic anhydride(OSAn) and their degree of substitution (DS), reaction efficiency(RE), residual octenylsuccinic acid (OSA), and physicochemical properties were compared with those of the native corn starch. DS increased with increase of OSAn and RE was much nearly the same regardless of increased of OSAn. The content of residual of residual OSA was significantly lower than that of regulation of food additives. And as washing frequency of dispersion of the reactant was increased, the content of residual OSA of octenylsuccinated starch was decreased. Raid Visco-Analyzer initial pasting temperature and setback of octenylsuccinated starches decreased whereas peak viscosity and breakdown increased. When DS of octenylsuccinated starches increased, temperature of initial gelatinization of octenylscuccinated starches drastically decreased. The octenylsuccinated starches also formed clearer pastes. The solubility was much nearly the same regardless of increase of DS at 7$0^{\circ}C$ but the swelling power increased 1.2~1.7 times higher than that of native corn starch at 7$0^{\circ}C$. The water binding capacity of octenylsuccinated starches also decreased.

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Structure-property relationship of melt intercalated maleated polyethylene nanocomposites

  • Reddy, M.M.;Gupta, Rahul K.;Bhattacharya, S.N.;Parthasarathy, R.
    • Korea-Australia Rheology Journal
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    • v.19 no.3
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    • pp.133-139
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    • 2007
  • Low density polyethylene nanocomposites were prepared by melt intercalating maleic anhydride grafted polyethylene and montmorillonite clay. It has been found that maleic anhydride has promoted strong interactions between polyethylene and montmorillonite, leading to the homogeneous dispersion of clay layers. Rheological experiments revealed that prepared nanocomposites exhibited shear thinning behaviour. Polyethylene nanocomposites exhibited an increase in steady shear viscosities compared to virgin polyethylene owing to strong polymer clay interactions. The tensile strength of nanocomposites was improved but elongation at break decreased considerably. Also, barrier properties improved significantly with montmorillonite content.

Properties of Biodegradable Films Produced from Rice Bran and Roasted Sesame Meal through Chemical Modifications

  • Bae, Dongho;Kim, Woo Jung;Jang, In Sook
    • Journal of Applied Biological Chemistry
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    • v.43 no.2
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    • pp.79-85
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    • 2000
  • Biodegradable films were prepared from roasted sesame meal and rice bran. Acetic anhydride, succinic anhydride, and formaldehyde were added to the film-forming solutions, and their effects on tensile strength, percent elongation, water vapor permeability, and water solubility of the films were studied. Roasted sesame meal did not form film without acylation or addition of formaldehyde. Acylated roasted sesame films had higher tensile strength and water-solubility, and lower % elongation than rice bran films. Acylation with acetic and succinic anhydrides increased tensile strength, percent elongation, and water solubility of rice bran films, but decreased water vapor permeability. Treatment with formaldehyde increased tensile strength of roasted sesame and rice bran films and % elongation of rice bran films, while reducing water-solubility of roasted sesame and rice bran films and water vapor permeability of rice bran films.

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Effects of Reactive Compatibilizers on the Morphology and Properties of Natural Rubber/SiO2 Composites

  • Lee, Min Young;Park, Jin Young;Song, Ki Chan;Kim, Su Kyung
    • Elastomers and Composites
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    • v.51 no.2
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    • pp.106-112
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    • 2016
  • Maleimidopropyltriethoxysilane grafted natural rubber (MISNR) was prepared by reaction of maleic anhydride grafted natural rubber and 3-aminopropyl triethoxysilane. MISNR was used as the compatibilizer of natural rubber/silica composites. The composites were prepared by two-step mixing procedures. The final mixtures were cured with optimum cure condition, which was established by a rheometer. Effects of the amounts of compatibilizer in the composites on the cure characteristics, morphology, thermal stability, and physical and mechanical behaviors were investigated. The composites having MISNR had shown cure characteristics and physical and mechanical properties superior to those without MISNR. Silica particles in the former appeared to be more uniform and reduced in size compared with the latter. The effects of the types of silica were also evaluated.

Application Study of Skin Beauty Culture, Green Laver Culture and Synthesis of ${\alpha}$-Chloro Substituted Chitosan Succinic Acid Derivatives (${\alpha}$-Chloro 치환기를 갖는 Chitosan Succinic Acid 유도체 합성 및 피부미용과 해태 김 양식 응용 연구)

  • Ryu, Soung-Ryual
    • Journal of Integrative Natural Science
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    • v.4 no.4
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    • pp.323-331
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    • 2011
  • In this study, ${\alpha}$-chlorosuccinic acid was synthesized through the reaction of maleic anhydride with HCl(g), (UV)250 nm~300 nm wavelength in presence of $CCl_4$. For the second reaction of N-(monochloro)succinic acid contained glucosamine derivatives(I) was accomplished by a modification of the general acylation using excess ${\alpha}$-chlorosuccinic anhydride in the presence of 2% acetic acid with methanol condition as a solvent at elevated temperature($70^{\circ}C$). We considered organic acid derivatives were useful especially for treatment for the cultivating porphyra.