Spectral study on the oxidation products of conjugated dienes of high molecular weight

1965 ◽  
Vol 6 (1) ◽  
pp. 38-42
Author(s):  
R. M. Aseeva ◽  
Yu. G. Aseev ◽  
A. A. Berlin ◽  
V. I. Kasatochkin
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Spectral Study ◽  
Conjugated Dienes ◽  
Oxidation Products

High-Molecular-Weight, High-Unsaturation Copolymers of Isobutylene and Conjugated Dienes. I. Synthesis

1976 ◽  
Vol 49 (4) ◽  
pp. 960-966 ◽  
Author(s):  
W. A. Thaler ◽  
D. J. Buckley
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Cationic Polymerization ◽  
Critical Role ◽  
Conjugated Dienes ◽  
Solution Properties ◽  
Insight Into

Abstract This investigation has provided insight into the critical role of solution properties on the course of cationic polymerization and has led to a technique for reconciling the opposing demands for synthesis of isoolefin-diene copolymers both free from gel and high in molecular weight. By this technique, the synthesis of a broad range of intermediate-unsaturation elastomers of quality has been realized.

The composition of grape cuticle wax

1965 ◽  
Vol 18 (7) ◽  
pp. 1059 ◽  
Author(s):  
F Radler ◽  
DHS Horn
Keyword(s):  
Fatty Acids ◽  
Molecular Weight ◽  
High Molecular Weight ◽  
Oleanolic Acid ◽  
Light Petroleum ◽  
Oxidation Products ◽  
Straight Chain ◽  
Neutral Alumina ◽  
Chain Lengths ◽  
Long Chain

The cuticle wax of the grape is composed of a soft wax (30%) readily removed by light petroleum and a hard wax (30%), mainly oleanolic acid, removed by chloroform. The soft wax of the fresh grape is composed chiefly of long-chain alcohols together with smaller amounts of aldehydes, esters, fatty acids, hydrocarbons, oleanolic acid, and small amounts of high molecular weight substances. The soft wax of dried grapes is similar in composition but contains no aldehydes and larger amounts of high molecular weight substances and oxidation products. The aldehydes, unusual wax components, are straight chain and range from C16 to C32 with the even chain-lengths predominating. They were destroyed by neutral alumina but can be chromatographed on silicic acid.

The distribution of oxidation products in irradiated ultra-high molecular weight polyethylene

1995 ◽  
Vol 49 (2) ◽  
pp. 239-244 ◽  
Author(s):  
P. O'Neill ◽  
C. Birkinshaw ◽  
J.J. Leahy ◽  
M. Buggy ◽  
T. Ashida
Keyword(s):  
Molecular Weight ◽  
High Molecular Weight ◽  
Oxidation Products ◽  
Ultra High Molecular Weight

scholarly journals Dependence of particle nucleation and growth on high molecular weight gas phase products during ozonolysis of α-pinene

2013 ◽  
Vol 13 (4) ◽  
pp. 9319-9354 ◽  
Author(s):  
J. Zhao ◽  
J. Ortega ◽  
M. Chen ◽  
P. H. McMurry ◽  
J. N. Smith
Keyword(s):  
Molecular Weight ◽  
Gas Phase ◽  
High Molecular Weight ◽  
Mass Range ◽  
Oxidation Products ◽  
Ionization Mass ◽  
Particle Nucleation ◽  
Acid Vapor ◽  
Molecular Weights ◽  
20 Nm

Abstract. We report the first time-dependent measurements of high molecular weight (up to 700 amu) gas-phase oxidation products from α-pinene ozonolysis in an aerosol chamber under dry and low NOx conditions. Measurements of products having mole fractions ranging from 10−14 to −11 were carried out with a chemical ionization mass spectrometer (the Cluster CIMS). Most products that were correlated with number concentrations of the smallest particles measured (10–20 nm) had molecular weights in the 430–560 amu range. Those products are proposed to be likely responsible for the initial nuclei formation and the early growth of the freshly-nucleated particles based on their high molecular weights and chemical identities, both of which suggest low volatility compounds. Another group of oxidation products in the lower mass range of 140–380 amu was well correlated with particles larger than 20 nm. We postulate that those products contributed to the later growth of particles (i.e. larger than 20 nm in diameter). Although particle nucleation in this study was primarily due to condensation of oxidation products from α-pinene ozonolysis, the involvement of residual sulfuric acid vapor in particle nucleation cannot be totally excluded.

scholarly journals Biogenic, urban, and wildfire influences on the molecular composition of dissolved organic compounds in cloud water

2017 ◽  
Author(s):  
Ryan D. Cook ◽  
Ying-Hsuan Lin ◽  
Zhuoyu Peng ◽  
Eric Boone ◽  
Rosalie K. Chu ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Organic Carbon ◽  
High Molecular Weight ◽  
Organic Compounds ◽  
Aqueous Phase ◽  
Water Samples ◽  
Cloud Water ◽  
Molecular Composition ◽  
Oxidation Products ◽  
Aerosol Formation

Abstract. Organic aerosol formation and transformation occurs within aqueous aerosol and cloud droplets, yet little is known about the composition of high molecular weight organic compounds in cloud water. Cloud water samples collected at Whiteface Mountain, New York during August–September 2014 were analyzed by ultrahigh-resolution mass spectrometry to investigate the molecular composition of dissolved organic carbon, with focus on sulfur- and nitrogen-containing compounds. Organic molecular composition was evaluated in the context of cloud water inorganic ion concentrations, pH, and total organic carbon concentrations to gain insights into the sources and aqueous phase processes of the observed high molecular weight organic compounds. The molecular composition of the cloud water depended on the influencing sources (biogenic, urban, wildfire) and showed evidence of aqueous-phase processes. Cloud water acidity was correlated with the average oxygen:carbon ratio of the organic constituents, suggesting the influence of aqueous acid-catalyzed oxidation processes. Organosulfate compounds, with both biogenic and anthropogenic volatile organic compound precursors, were detected for cloud water samples influenced by air masses that had traveled over forested and populated areas. Oxidation products of long-chain (C10-12) alkane precursors were detected during urban influence. Influence of Canadian wildfires resulted in increased numbers of identified sulfur-containing compounds and oligomeric species, including those formed through aqueous-phase reactions involving methylglyoxal. Light absorbing aqueous-phase products of syringol and guaiacol oxidation were observed in the wildfire-influenced samples, and dinitroaromatic compounds were observed in all cloud water samples (wildfire, biogenic/urban, and urban-influenced).

scholarly journals Size-dependent chemical ageing of oleic acid aerosol under dry and humidified conditions

2016 ◽  
Vol 16 (24) ◽  
pp. 15561-15579 ◽  
Author(s):  
Suad S. Al-Kindi ◽  
Francis D. Pope ◽  
David C. Beddows ◽  
William J. Bloss ◽  
Roy M. Harrison
Keyword(s):  
Molecular Weight ◽  
Particle Size ◽  
Oleic Acid ◽  
Relative Humidity ◽  
High Molecular Weight ◽  
Oxidation Products ◽  
Nonanoic Acid ◽  
Reaction Products ◽  
Scanning Mobility Particle Sizer ◽  
Model Aerosol

Abstract. A chemical reaction chamber system has been developed for the processing of oleic acid aerosol particles with ozone under two relative humidity conditions: dry and humidified to 65 %. The apparatus consists of an aerosol flow tube, in which the ozonolysis occurs, coupled to a scanning mobility particle sizer (SMPS) and an aerosol time-of-flight mass spectrometer (ATOFMS) which measure the evolving particle size and composition. Under both relative humidity conditions, ozonolysis results in a significant decrease in particle size and mass which is consistent with the formation of volatile products that partition from the particle to the gas phase. Mass spectra derived from the ATOFMS reveal the presence of the typically observed reaction products: azelaic acid, nonanal, oxononanoic acid and nonanoic acid, as well as a range of higher molecular weight products deriving from the reactions of reaction intermediates with oleic acid and its oxidation products. These include octanoic acid and 9- and 10-oxooctadecanoic acid, as well as products of considerably higher molecular weight. Quantitative evaluation of product yields with the ATOFMS shows a marked dependence upon both particle size association (from 0.3 to 2.1 µm diameter) and relative humidity. Under both relative humidity conditions, the percentage residual of oleic acid increases with increasing particle size and the main lower molecular weight products are nonanal and oxononanoic acid. Under dry conditions, the percentage of higher molecular weight products increases with increasing particle size due to the poorer internal mixing of the larger particles. Under humidified conditions, the percentage of unreacted oleic acid is greater, except in the smallest particle fraction, with little formation of high molecular weight products relative to the dry particles. It is postulated that water reacts with reactive intermediates, competing with the processes which produce high molecular weight products. Whilst the oleic acid model aerosol system is of limited relevance to complex internally mixed atmospheric aerosol, the generic findings presented in this paper give useful insights into the nature of heterogeneous chemical processes.

scholarly journals Size dependent chemical ageing of oleic acid aerosol under dry and humidified conditions

2016 ◽  
Author(s):  
Suad Al-Kindi ◽  
Francis D. Pope ◽  
David C. Beddows ◽  
William J. Bloss ◽  
Roy M. Harrison
Keyword(s):  
Molecular Weight ◽  
Particle Size ◽  
Oleic Acid ◽  
Relative Humidity ◽  
High Molecular Weight ◽  
Oxidation Products ◽  
Nonanoic Acid ◽  
Reaction Products ◽  
Scanning Mobility Particle Sizer ◽  
Model Aerosol

Abstract. A chemical reaction chamber system has been developed for the processing of oleic acid aerosol particles with ozone under two relative humidity conditions: dry and humidified to 65 % R.H. The apparatus consists of an aerosol flow tube, in which the ozonolysis occurs, coupled to a scanning mobility particle sizer (SMPS) and an aerosol time-of-flight mass spectrometer (ATOFMS) which measure the evolving particle size and composition. Under both relative humidity conditions, ozonolysis results in a significant decrease in particle size and mass which is consistent with the formation of volatile products that partition from the particle to the gas phase. Mass spectra derived from the ATOFMS reveal the presence of the typically observed reaction products: azaleic acid, nonanal, oxononanoic acid and nonanoic acid, as well as a range of higher molecular weight products deriving from the reactions of reaction intermediates with oleic acid and its oxidation products. These include octanoic acid, and 9- and 10-oxooctadecanoic acid, as well as products of considerably higher molecular weight. Quantitative evaluation of product yields with the ATOFMS shows a marked dependence upon both particle size association (from 0.3 to 2.1 µm diameter) and relative humidity. Under dry conditions, the percentage residual oleic acid increases with increasing particle size, as does the percentage of higher molecular weight products, due to the poorer internal mixing of the larger particles. The main lower molecular weight products are nonanal and oxonononic acid. Under humidified conditions, the percentage unreacted oleic acid is greater, except in the smallest particle fraction, and oxononanoic acid dominates the product distribution, with little formation of high molecular weight products relative to the dry particles. It is postulated that water reacts with reactive intermediates, competing with the processes which produce high molecular weight products. Whilst the oleic acid model aerosol system is of limited relevance to complex internally mixed atmospheric aerosol, the generic findings presented in this paper give useful insights into the nature of heterogeneous chemical processes.

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