Methods for the Synthesis of Polyethereketone

2018 ◽  
Vol 935 ◽  
pp. 27-30
Author(s):  
K.T. Shakhmurzova ◽  
Zh.I. Kurdanova ◽  
Arthur E. Baikaziev ◽  
Karina Kh. Teunova ◽  
Azamat A. Zhansitov ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Aromatic Hydrocarbons ◽  
Electrophilic Substitution ◽  
Methylene Chloride ◽  
Dicarboxylic Acids ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Low Molecular Weight ◽  
Monocarboxylic Acids ◽  
Synthesis Time ◽  
Aromatic Dicarboxylic Acids

The data on the methods for the preparation of polyetherketones by electrophilic and nucleophilic methods are considered and generalized. It is shown that polyetherketones by electrophilic substitution are carried out as homopolycondensation aromatic monocarboxylic acids and their halides and polycondensation of polynuclear aromatic hydrocarbons with aromatic dicarboxylic acids or their halides, and phosgene in organic solvents (1,2-dichloroethane, methylene chloride, nitrobenzene and etc.) in the presence of Ziegler-Natt catalysts. However, this process has not found an industrial application in view of such disadvantages as low yield of the desired product, the formation of a polymer with low molecular weight, synthesis time (15-40 hours), the use of large amounts of catalyst, the complexity of polymer purification of it.

Extraction of low molecular weight polynuclear aromatic hydrocarbons from ashes of coal-operated power plants

1987 ◽  
Vol 59 (17) ◽  
pp. 2066-2069 ◽  
Author(s):  
Filippo. Mangani ◽  
Achille. Cappiello ◽  
Giancarlo. Crescentini ◽  
Fabrizio. Bruner ◽  
Loretta. Bonfanti
Keyword(s):  
Molecular Weight ◽  
Aromatic Hydrocarbons ◽  
Power Plants ◽  
Polynuclear Aromatic Hydrocarbons ◽  
Low Molecular Weight

Hygroscopic behavior and chemical reactivity of aerosols generated from mixture solutions of low molecular weight dicarboxylic acids and NaCl

2021 ◽  
Author(s):  
Xue Li ◽  
Li Wu ◽  
Ji-Soo Lee ◽  
Chul-Un Ro
Keyword(s):  
Molecular Weight ◽  
Chemical Reactivity ◽  
Dicarboxylic Acids ◽  
Sea Spray ◽  
Low Molecular Weight ◽  
Hygroscopic Behavior

Ambient sea spray aerosols (SSAs) have been reported to undergo reactions with low molecular weight dicarboxylic acids (LMW DCAs). In the present study, the hygroscopic behavior of aerosols generated from...

scholarly journals Effect of WC/Ni–Cr additive on changes in the composition of an atmospheric residue in the course of cracking

2019 ◽  
Vol 17 (2) ◽  
pp. 499-508 ◽  
Author(s):  
Galina S. Pevneva ◽  
Natalya G. Voronetskaya ◽  
Nikita N. Sviridenko ◽  
Anatoly K. Golovko
Keyword(s):  
Molecular Weight ◽  
Tungsten Carbide ◽  
Aromatic Hydrocarbons ◽  
Aromatic Compounds ◽  
Low Molecular Weight ◽  
Nickel Chromium ◽  
Atmospheric Residue ◽  
Sulfur Containing ◽  
Catalytic Additive ◽  
Sulfur Containing Compounds

AbstractThe paper presents the results of investigation of changes in the composition of hydrocarbons and sulfur-containing compounds of an atmospheric residue in the course of cracking in the presence of a tungsten carbide–nickel–chromium (WC/Ni–Cr) catalytic additive and without it. The cracking is carried out in an autoclave at 500 °C for 30 min. The addition of the WC/Ni–Cr additive promotes the deepening of reactions of destruction not only of resins and asphaltenes, but also high molecular weight naphthene-aromatic compounds of the atmospheric residue. It is shown that the content of low molecular weight C9–C17 n-alkanes and C9–C10 alkylbenzenes rose sharply in the products of cracking with addition of WC/Ni–Cr in comparison with those produced without the additive. Alkyl- and naphthene-substituted aromatic hydrocarbons of benzene, naphthalene, phenanthrene series, polyarenes, benzo- and dibenzothiophenes are identified.

Gas/particle partitioning of low-molecular-weight dicarboxylic acids at a suburban site in Saitama, Japan

2012 ◽  
Vol 47 ◽  
pp. 546-553 ◽  
Author(s):  
Linfa Bao ◽  
Mariko Matsumoto ◽  
Tsutomu Kubota ◽  
Kazuhiko Sekiguchi ◽  
Qingyue Wang ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Dicarboxylic Acids ◽  
Low Molecular Weight ◽  
Suburban Site

scholarly journals Distributions and sources of low-molecular-weight monocarboxylic acids in gas and particles from a deciduous broadleaf forest in northern Japan

2019 ◽  
Vol 19 (4) ◽  
pp. 2421-2432 ◽  
Author(s):  
Tomoki Mochizuki ◽  
Kimitaka Kawamura ◽  
Yuzo Miyazaki ◽  
Bhagawati Kunwar ◽  
Suresh Kumar Reddy Boreddy
Keyword(s):  
Molecular Weight ◽  
Gas Phase ◽  
Nonanoic Acid ◽  
Low Molecular Weight ◽  
Forest Site ◽  
Particle Phase ◽  
Broadleaf Forest ◽  
Monocarboxylic Acids ◽  
Deciduous Broadleaf Forest ◽  
Northern Japan

Abstract. To better understand the distributions and sources of low-molecular-weight (LMW) monocarboxylic acids (monoacids) in the forest atmosphere, we conducted simultaneous collection of gaseous and particulate samples at a deciduous broadleaf forest site in northern Japan. LMW normal (C1–C10), branched (iC4–iC6), hydroxyl (glycolic and lactic) and aromatic (benzoic) monoacids were detected in the gas and particle phases. The dominant LMW monoacids in gas phase were formic (mean: 953 ng m−3) and acetic (528 ng m−3) acids followed by propionic (37 ng m−3) or isopentanoic (42 ng m−3) acid. In the particle phase, isopentanoic (159 ng m−3) was dominant, followed by acetic (104 ng m−3) and formic (71 ng m−3) or lactic (65 ng m−3) acids. Concentrations of LMW monoacids did not show correlations with anthropogenic tracers such as nss-SO42- and NO3-, indicating that anthropogenic contribution is not important. Concentrations of C1–C6 monoacids in the gas phase showed positive correlations (r2=0.21–0.91) with isobutyric acid (iC4), which may be produced by microbial activity in soil. The forest soil may be a source of gaseous C1–C6 monoacids in the forest atmosphere. Acetic acid in the particle phase positively correlated with nonanoic acid (C9) (r2=0.63), suggesting that formation of acetic and nonanoic acids is associated with the oxidation of biogenic unsaturated fatty acids in the aerosol phase, in addition to photochemical oxidation of biogenic volatile organic compounds. The particle-phase fractions (Fp) of formic and acetic acids showed negative correlation with ambient temperature (C1: r2=0.49, C2: r2=0.60) but showed positive correlation with relative humidity (C1: r2=0.30, C2: r2=0.55) in daytime, suggesting that these meteorological parameters are important for the gas and particle portioning of monoacids in the forest atmosphere.

Determination of Low Molecular Weight Dicarboxylic Acids in Root Exudates by Gas Chromatography

1995 ◽  
Vol 43 (4) ◽  
pp. 956-959 ◽  
Author(s):  
Anna M. Szmigielska ◽  
Ken C. J. Van Rees ◽  
Grzegorz Cieslinski ◽  
Pan Ming Huang ◽  
Doug R. Knott
Keyword(s):  
Molecular Weight ◽  
Gas Chromatography ◽  
Root Exudates ◽  
Dicarboxylic Acids ◽  
Low Molecular Weight
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