Effects of Sulfur on the Peroxide Cure of EPDM and Divinylbenzene Compounds

1979 ◽  
Vol 52 (1) ◽  
pp. 74-83 ◽  
Author(s):  
R. Fujio ◽  
M. Kitayama ◽  
N. Kataoka ◽  
S. Anzai
Keyword(s):  
Young’S Modulus ◽  
Microscopic Study ◽  
Mechanical Behaviour ◽  
Young's Modulus ◽  
Reaction Products ◽  
Electron Microscopic ◽  
Swelling Equilibrium ◽  
Rupture Energy ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Abstract By introducing a small amount (0.15 part by weight) of sulfur into EPDM/DVB/DCPO compounds, Young's modulus and the rupture energy of the vulcanizates are markedly increased. The swelling equilibrium and dynamic mechanical behaviour show that an increase in crosslinking is achieved by the addition of sulfur. Moreover, electron microscopic study has revealed that vulcanizates from sulfur containing compounds have a better state of dispersion of the resinous poly-DVB phase than those without sulfur. When the amount of sulfur is too great (>0.20 part), Young's modulus of the vulcanizate is markedly reduced, mainly because of insufficient polymerization of DVB. Sulfur apparently acts as a retarder of DVB polymerization. Furthermore, it is proposed that some reaction products of peroxide and sulfur could be the initiator of this polymerization.

scholarly journals An Experimental–Numerical Approach for Modelling the Mechanical Behaviour of a Pneumatic Tyre for Agricultural Machines

2020 ◽  
Vol 10 (10) ◽  
pp. 3481 ◽  
Author(s):  
Alexandros Sotirios Anifantis ◽  
Maurizio Cutini ◽  
Marco Bietresato
Keyword(s):  
Young’S Modulus ◽  
Mechanical Behaviour ◽  
Young's Modulus ◽  
Elastic Field ◽  
Numerical Approach ◽  
Fe Model ◽  
Real Scale ◽  
Tread Rubber ◽  
Agricultural Machines

The mechanical behaviour of an agricultural tyre is a matter of extreme interest as it is related to the comfort of operators, to the adherence of agricultural machines, and to the compaction of agricultural soil. Moreover, the deformability of the tyres plays a fundamental role in vehicle stability in terms of side rollover. The behaviour of a loaded tyre during its deformation is complex, due to the combined contributions of the carcass components, the tread rubber and the air contained within it. Therefore, this study proposes an experimental–numerical approach for the mechanical characterization of agricultural tyres based on real-scale experiments and matches these results with a finite-element (FE) model. The tyre flattening in the elastic field has been described using two coefficients (Young’s modulus “E”, Poisson’s ratio “ν”), whose values have been identified with an iterative FEM procedure. The proposed approach was applied to two different tyres (420/85 R24 and 460/85 R34), each one inflated at two different pressures (1.0 bar and 1.6 bar). Young’s modulus was appreciated to be highly variable with the inflation pressure “p” of the tyres. Furthermore, the response surface methodology was applied to find two mathematical regression models, useful for studying the variations of the tyre footprint dimensions according to the type of tyre. This simple approach can be applied in other simulations without suffering any loss of accuracy in the description of the phenomenon.

Effect of Fe2+ on Ascorbic Acid - Methionine Pattern is Formed by the Reaction of Aroma Compounds

2013 ◽  
Vol 781-784 ◽  
pp. 591-595
Author(s):  
Di Liu ◽  
Yu Shao ◽  
Xiao Hong Yang
Keyword(s):  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Degradation Products ◽  
Model Reaction ◽  
Flavor Compounds ◽  
Gas Chromatography Mass Spectrometry ◽  
Reaction Products ◽  
Competitive Reaction ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

By solid phase microextraction - Gas Chromatography - mass spectrometry (SPME-GC-MS) technique against acid and methionine bad blood (ASA-Met) model of the reaction products were identified, studied the effect of Fe2+ on the formation of flavor compounds in the model reaction. 27 flavour compounds of furan, pyrazine, thiophene, sulfur and other compounds, were identified, of which, sulfur-containing compounds such as aliphatic cyclic sulfides, sulfide, pyrazine is the main flavor components. Fe2+ was added to the model in the system, on one hand the about adding some sulfur compounds yield, pyrazine compounds significantly increase; on the other hand, Thiophenes significantly reduced compounds or even disappear. This shows that in the model reaction, Fe2+ promotes the thermal degradation of Met, at the same time, suggesting that Fe2+ as oxidant to promote NH3, NH3 and H2S to generate competitive reaction and ASA degradation products formed compounds containing nitrogen, resulting in reduced Thiophenes compounds yield.

Effect of Cu2+ on Ascorbic Acid - Methionine Pattern is Formed by the Reaction of Aroma Compounds

2013 ◽  
Vol 803 ◽  
pp. 103-107
Author(s):  
Fan Peng ◽  
Xiao Hong Yang
Keyword(s):  
Solid Phase Microextraction ◽  
Solid Phase ◽  
Gas Chromatography Mass Spectrometry ◽  
Reaction Products ◽  
Yield Increase ◽  
The One ◽  
Main Components ◽  
Sulfur Containing ◽  
Form Effect ◽  
Sulfur Containing Compounds

Using solid phase microextraction - Gas Chromatography - mass spectrometry (SPME-GC-MS) technique to acid and methionine bad blood (ASA-Met) analysis of the reaction products, the influence of Cu2+ on the model reaction flavor compounds form effect. 27 flavour compounds thiophene, furan, pyrazine, sulfur and other compounds, were identified, including sulfur compounds, such as aliphatic cyclic sulfides, sulfide, thiophene, pyrazine as main components. Cu2+ was added to the reaction mode, on the one hand, sulfur-containing compounds yield increased significantly; on the other hand, increasing the thiophene, pyrazine compound types, yield increase.

scholarly journals Mechanical Behaviour at Low Strains of LDPE Foams with Cell Sizes in the Microcellular Range: Advantages of Using These Materials in Structural Elements

2008 ◽  
Vol 27 (6) ◽  
pp. 347-362 ◽  
Author(s):  
M.A. Rodriguez-Perez ◽  
J. Lobos ◽  
C.A. Perez-Muñoz ◽  
J.A. de Saja ◽  
L. Gonzalez ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Cell Size ◽  
Mechanical Behaviour ◽  
Cellular Structure ◽  
Mechanical Response ◽  
Young's Modulus ◽  
Production Method ◽  
Constant Density ◽  
Structural Elements ◽  
Compression Moulding

This paper presents the production method and the compressive mechanical response at low strains for a collection of polyethylene foams with high densities and cell sizes in the microcellular range. The materials were produced using an improved compression moulding technique that allows and independent control of density and cell size. The materials had a relative density between 0.27 and 0.92, an homogeneous and multi-structured cellular structure with dense skin and foamed core and cell sizes in the range 30 to 100 microns. The Young's modulus decreased with density. For relative densities higher than 0.7, the reduced Young's modulus of the foams was higher than that of the solid. In addition, it has been proved that variations in the cell size at constant density did not influence the Young's modulus. The advantages of using these materials for the production of plastic pipes have been analysed. In comparison with a solid pipe a reduction of the weight of foamed pipes loaded in compression of up to 40% can be reached.

scholarly journals Composites Based on Polypropylene and Talc: Processing Procedure and Prediction Behavior by Using Mathematical Models

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Laiza Marinho Racca ◽  
Elen Beatriz Acordi Vasques Pacheco ◽  
Luiz Carlos Bertolino ◽  
Cristiane Xavier da Silva Campos ◽  
Monica Calixto de Andrade ◽  
...  
Keyword(s):  
Particle Size ◽  
Mathematical Models ◽  
Young’S Modulus ◽  
Mechanical Behaviour ◽  
Young's Modulus ◽  
Tensile Tests ◽  
Reinforcing Effect ◽  
Thermoplastic Matrix ◽  
Processing Procedure ◽  
Sem Analyses

iPP/Talc composites were produced, with different methods of filler addition in iPP matrix. Two different grades of Talc were used for comparison. The tensile tests results showed that talc particles promoted an improvement in composite rigidity, indicating the reinforcing effect of the talc particles in the iPP matrix. However, PP/talc-based composites that were prepared from a masterbatch and with talc grade with smaller particle size showed a better efficiency on dispersion/distribution of particle filler on the thermoplastic matrix, resulting in an improvement in Young’s modulus property, even with higher filler contents. SEM analyses evaluated the composite morphologies and different mathematical models were used as a tool on prediction of mechanical behaviour of the materials. It was observed that the results of Young’s modulus of the composites can be adjusted by different models, depending on the talc characteristics and the mixing procedure used.

Numerical Simulation of the Mechanical Behaviour of the Multi-Walled Carbon Nanotubes

2017 ◽  
Vol 47 ◽  
pp. 106-119 ◽  
Author(s):  
Nataliya A. Sakharova ◽  
André F.G. Pereira ◽  
Jorge M. Antunes ◽  
José Valdemar Fernandes
Keyword(s):  
Numerical Simulation ◽  
Carbon Nanotubes ◽  
Young’S Modulus ◽  
Mechanical Behaviour ◽  
Young's Modulus ◽  
Element Model ◽  
Multi Walled Carbon Nanotubes ◽  
Simplified Finite Element Model ◽  
Walled Carbon Nanotubes ◽  
Bending Loading

The mechanical behaviour of non-chiral multi-walled carbon nanotubes under tensile and bending loading conditions was investigated. For this purpose, a simplified finite element model of armchair and zigzag multi-walled carbon nanotubes, which does not take into account the van der Waals forces acting between layers, was tested in order to evaluate their tensile and bending rigidities, as well as the Young’s modulus. The current numerical simulation results are compared with data reported in the literature. The robustness of the simplified model for evaluation of the Young’s modulus of multi-walled carbon nanotubes is discussed.

Effect of Material Composition on Mechanical Properties of Ceramics-Metal Composite Materials

2011 ◽  
Vol 462-463 ◽  
pp. 100-105 ◽  
Author(s):  
Tomoyuki Fujii ◽  
Keiichiro Tohgo ◽  
Hiroyasu Araki ◽  
Katsunori Wakazono ◽  
Masaki Ishikura ◽  
...  
Keyword(s):  
Fracture Toughness ◽  
Young’S Modulus ◽  
Vickers Hardness ◽  
Bending Strength ◽  
Volume Fraction ◽  
Young's Modulus ◽  
Pure Titanium ◽  
Metal Composite ◽  
Reaction Products ◽  
Pressing Method

This paper deals with fabrication and strength evaluation of biocompatible composites consisting of partially stabilized zirconia (PSZ) and pure titanium (Ti). The biocompatible composites of PSZ-Ti were fabricated by a hot pressing method of powder metallurgy. A volume ratio of PSZ and Ti was changed. Four-point bending tests and Vickers hardness tests of the PSZ-Ti composite were performed to determine the Young's modulus, bending strength, Vickers hardness and fracture toughness. These properties were characterized as a function of Ti volume fraction. The Young's modulus and Vickers hardness were higher than the prediction of the rule of mixture. The bending strength and fracture toughness were decreased with increasing Ti content. To discuss these results from a viewpoint of reaction products, the components of raw powders and sintered composites were investigated by X-ray diffraction analysis. It is concluded that oxide of titanium and other reaction products were created after sintering and they affected the mechanical performances of the composites.

scholarly journals Mechanical Behaviour of Nanostructured Iron Fabricated by Severe Plastic Deformation under Diffusion Flow of Nitrogen

2006 ◽  
Vol 503-504 ◽  
pp. 645-650 ◽  
Author(s):  
A.I. Yurkova ◽  
A.V. Byakova ◽  
A.V. Belots'ky ◽  
Yu.V. Milman ◽  
Sergey N. Dub
Keyword(s):  
Grain Size ◽  
Young’S Modulus ◽  
Mechanical Behaviour ◽  
Young's Modulus ◽  
Grain Structure ◽  
Triple Junctions ◽  
Fine Grained ◽  
Friction Treatment ◽  
Iron Modification ◽  
Nanocrystalline Iron

Specific features of mechanical behaviour of ultra fine grained iron subjected to friction treatment with nitriding (FN) were clarified by comparison with that induced by friction treatment (FT) with air. Mechanical parameters such as Young’s modulus, nanohardness, and plasticity characteristic δA were found to be of high sensitive both to the scale of grain structure and to iron modification by nitrogen. Young’s modulus tends to decrease and Hall-Petch low fails to describe correlation between grain structure and hardness for submicro-grained and nanocrystalline iron. Hall-Petch coefficient, ky, decreases as grain size decreases within submicro-grained and, then, nano grained sections and it takes even negative value in nano grained section modified by nitrogen. Parameter δA is found to be dependent on combination of hardness and Young’s modulus, resulting in its variation with decreasing the grain size. The presence of secondary nanocrystalline Fe4N phase fundamentally changes mechanical behaviour of nanocrystalline iron, leading to strengthening the grain boundaries and triple junctions.

Synthesis of possible o-thioquinone methide precursors

2008 ◽  
Vol 86 (2) ◽  
pp. 119-123 ◽  
Author(s):  
Kirill A Kolmakov ◽  
A Jerry Kresge
Keyword(s):  
Temperature Sensitive ◽  
Reaction Products ◽  
Flash Vacuum Pyrolysis ◽  
Vacuum Pyrolysis ◽  
Synthetic Accessibility ◽  
Electron Donating Groups ◽  
Sulfur Containing ◽  
Sulfur Containing Compounds

Investigating the synthetic accessibility of o-thioquinone methide precursors containing electron donating groups, we prepared four methyl- and methoxy-substituted 2H-benzo[b]thiete derivatives by means of flash vacuum pyrolysis of the corresponding benzooxathiinone species. Methyl- and methoxy-substituted substrates proved to be compatible with the pyrolysis protocol. The pyrolysis can be performed at considerably lower temperatures and with higher yields than in previously reported syntheses of nonsubstituted 2H-benzo[b]thiete. Under proper conditions the reaction products can be isolated in excellent yields and with 100% purity, so the troublesome purification of temperature sensitive and volatile 2H-benzo[b]thiete derivatives becomes unnecessary. The sulfur-containing compounds so obtained are efficient o-thioquinone methide precursors and possible synthones for heterocyclic chemistry.Key words: 2H-benzo[b]thietes, flash vacuum pyrolysis, methyl-substituted, methoxy-substituted, o-thioquinone methide precursors.

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