Survey of Relations of Chemical Constituents in Polymer-Based Materials with Brittleness and its Associated Properties

2016 ◽  
Vol 10 (4s) ◽  
pp. 595-600 ◽  
Author(s):  
Witold Brostow ◽  
◽  
Haley E. Hagg Lobland ◽  
Keyword(s):  
Chemical Composition ◽  
Impact Strength ◽  
Free Volume ◽  
Chemical Constituents ◽  
Polymer Processing ◽  
Brittle Behavior ◽  
Composition And Structure ◽  
Common Thread

The property of brittleness for polymers and polymer-based materials (PBMs) is an important factor in determining the potential uses of a material. Brittleness of polymers may also impact the ease and modes of polymer processing, thereby affecting economy of production. Brittleness of PBMs can be correlated with certain other properties and features of polymers; to name a few, connections to free volume, impact strength, and scratch recovery have been explored. A common thread among all such properties is their relationship to chemical composition and morphology. Through a survey of existing literature on polymer brittleness specifically combined with relevant reports that connect additional materials and properties to that of brittleness, it is possible to identify chemical features of PBMs that are connected with observable brittle behavior. Relations so identified between chemical composition and structure of PBMs and brittleness are described herein, advancing knowledge and improving the capacity to design new and to choose among existing polymers in order to obtain materials with particular property profiles.

Structure and chemical composition of exopolysaccharides of frost-damaged sugar beet

2020 ◽  
pp. 34-39
Author(s):  
Aneta Antczak-Chrobot ◽  
Maciej Wojtczak
Keyword(s):  
Spectral Analysis ◽  
Chemical Composition ◽  
Sugar Beet ◽  
Total Acid ◽  
Average Molecular Mass ◽  
Central European ◽  
Composition And Structure ◽  
Monomeric Composition ◽  
Branched Structure ◽  
Different Origin

In this research paper, development of a procedure of isolation of exopolysaccharides from frost-damaged beet and an analysis of structural and chemical composition of polymers isolated from sugar beet of different origin are presented. Total acid hydrolysis degradation integrated with HPAEC-ED analysis has been utilized to confirm the monomeric composition of the separated polysaccharides. The implementation of NMR spectral analysis and SEC chromatography of the structure of exopolysaccharides has been investigated. The results demonstrate that the chemical composition and structure of exopolysaccharides depend on their origin. Typical exopolysaccharides from Central European beet roots consist mainly of glucose monomers – and they have low branched structure – about 90% of α-1,6 linkage which is typical for dextran. The exopolysaccharides isolated from Swedish beet are characterized by 50–60% fructose monomers. They contain only about 65% α-1,6 linkages. Exopolysaccharides extracted from various origin beet differ in average molecular mass. The molecular distribution is not normal.

scholarly journals Chemical Composition and Antimicrobial Activities of the Essential Oil From the Leaves of Pterocephalus hookeri

2020 ◽  
Vol 15 (12) ◽  
pp. 1934578X2098123
Author(s):  
Peng-fei Yang ◽  
Hui Lu ◽  
Qiong-bo Wang ◽  
Zhi-wei Zhao ◽  
Qiang Liu ◽  
...  
Keyword(s):  
Gas Chromatography ◽  
Chemical Composition ◽  
Essential Oil ◽  
Chemical Constituents ◽  
Antimicrobial Activities ◽  
Gas Chromatography Mass Spectrometry ◽  
Flame Ionization ◽  
And Staphylococcus Aureus ◽  
Antimicrobial Assay ◽  
Detailed Chemical

Detailed chemical constituents of essential oil from the Pterocephalus hookeri leaves and its antimicrobial activities were investigated in this study. The essential oil, obtained by hydrodistillation, was characterized by gas chromatography-flame ionization detection and gas chromatography-mass spectrometry analyses. Among the 90 identified compounds, hexadecanoic acid (21.27%), phytol (8.03%), furfural (7.08%), oleic acid (5.25%), and phytone (4.56%) were the major components. In the antimicrobial assay, the essential oil showed strong inhibitory activities against Escherichia coli, Candida albicans, and Staphylococcus aureus with minimum inhibitory concentration values of 31.3, 62.5, and 125 µg/mL, respectively. To our knowledge, this is the first report concerning chemical composition and antimicrobial activities of the essential oil from Pterocephalus hookeri.

scholarly journals The Effect of Chemical Composition and Structure on XPS Binding Energies in Zeolites

2003 ◽  
Vol 107 (3) ◽  
pp. 678-684 ◽  
Author(s):  
Onno L. J. Gijzeman ◽  
Ad J. M. Mens ◽  
Joop H. van Lenthe ◽  
Wifried J. Mortier ◽  
Bert M. Weckhuysen
Keyword(s):  
Chemical Composition ◽  
Binding Energies ◽  
Composition And Structure

The Thermal Volatilization of Petrodisel/Biodiesel from Waste Oil

2011 ◽  
Vol 347-353 ◽  
pp. 2656-2660
Author(s):  
Xiu Chen ◽  
Yin Nan Yuan ◽  
Yong Bin Lai
Keyword(s):  
Chemical Composition ◽  
Methyl Esters ◽  
Gas Chromatography Mass Spectrometry ◽  
Waste Oil ◽  
Compression Ignition Engine ◽  
Yield Information ◽  
Composition And Structure ◽  
Similar Chemical ◽  
Ignition Quality ◽  
Long Chain

Thermogravimetry (TG) has been employed to yield information on the thermal volatilization of the fuels since the volatility influences the ignition quality of the fuels in a compression ignition engine. The chemical composition of -10 petrodiesel (-10PD) and waste oil biodiesel (WME) was analyzed by gas chromatography-mass spectrometry. The thermal volatilization of biodiesel and its blends was investigated by TG and liquid volatile theory. Volatile index was put forward for describing biodiesel/petrodisel volatility. A good correlation model was proposed for calculate the biodiesel/petrodiesel volatility by biodiesel blending ratio. The study showed that -10PD and WME had similar chemical composition and structure. -10PD was mainly composed of long chain alkanes: C8–C26. WME was mainly composed of long chain fatty acid methyl esters: C14:0–C22:0, C16:1–C22:1, C18:2 and C18:3. The volatile indexes of WME and -10PD were 1.47E-04 and 3.64E-05, respectively. The biodiesel was considerably more volatile in comparison to the petrodiesel. The WME/-10PD volatility was better with increasing the biodiesel blending ratio.

scholarly journals QUALITY OF REACTION WOOD IN Eucalyptus TREES TILTED BY WIND FOR PULP PRODUCTION

CERNE ◽  
2017 ◽  
Vol 23 (3) ◽  
pp. 291-297
Author(s):  
Walter Torezani Neto Boschetti ◽  
Juarez Benigno Paes ◽  
Graziela Baptista Vidaurre ◽  
Marina Donária Chaves Arantes ◽  
João Gabriel Missia da Silva
Keyword(s):  
Chemical Composition ◽  
Chemical Constituents ◽  
Wood Quality ◽  
Basic Density ◽  
Kraft Pulping ◽  
Normal Wood ◽  
Reaction Wood ◽  
Opposite Wood ◽  
Holocellulose Content

ABSTRACT This study aims to evaluate the quality of normal, tension and opposite wood of eucalyptus trees lengthwise, in straight and inclined stems, affected by wind action. It also aims to explain the pulping parameters resultant from the quality of the wood. The trees were grouped into four tilt ranges, ranging from 0 to 50º, and the basic density, chemical composition of the wood, and performance in kraft pulping were assessed. Normal and tension wood had similar basic densities; while for opposite wood, the density was lower, being responsible for a decrease in reaction wood density. The chemical composition of the wood was influenced by the presence of reaction wood in the stem. Tension and opposite wood showed lower levels of extractives and lignin and higher holocellulose content when compared to normal wood, with favorable wood quality for pulping. The increase in holocellulose content and the reduction of lignin and extractives content contributed positively to a more delignified pulp and reduction of the Kappa number. However, after cooking the reaction wood under the same conditions as those of normal wood, reaction wood pulping tends to have a lower screen yields. Due to differences in basic density and chemical constituents between opposite and normal wood, it is recommended not to designate the opposite wood as normal wood.

scholarly journals Preparation and Characterization of Polymer Composite Materials Containing Magnetite

2021 ◽  
Vol 15 ◽  
pp. 1421-1428
Author(s):  
E. R. Sadretdinova ◽  
Thant Zin Hein
Keyword(s):  
Electron Microscopy ◽  
Phase Composition ◽  
Composite Materials ◽  
Ir Spectroscopy ◽  
Polymer Processing ◽  
Flow State ◽  
Standard Methods ◽  
Composition And Structure ◽  
Polyethylene Melt

In this work, magnetite nanoparticles are introduced into a polyethylene melt at the stage of a viscous-flow state by standard methods of polymer processing (extrusion), which makes it possible to obtain a nanocomposite with a uniform nanofiller distribution. The phase composition and structure of the nanocomposite were confirmed by XRF, electron microscopy, and IR spectroscopy. It is shown that the preparation of Fe3O4/LLDPE nanocomposites is not complicated by the appearance of unidentified phases and changes in the structure of the polymer matrix.

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