scholarly journals Biodiesel as a Plasticizer of a SBR-Based Tire Tread Formulation

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
Franco Cataldo ◽  
Ornella Ursini ◽  
Giancarlo Angelini
Keyword(s):  
Solubility Parameter ◽  
Methyl Esters ◽  
Mineral Oil ◽  
Nitrile Rubber ◽  
Polymer Chains ◽  
Rubber Matrix ◽  
Incremental Method ◽  
Low Elastic Modulus ◽  
Cloudy Solution ◽  
Different Content

The solubility parameter of a series of methyl esters of fatty acids, the components of biodiesel, was calculated using the group incremental method proposed by Van Krevelen. The solubility parameter of biodiesel was compared with that of a series of rubbers like EPDM, butyl rubber, polyisoprene, polybutadiene, SBR (with different content of styrene), and nitrile rubber (with different content of acrylonitrile) showing that biodiesel is an effective solvent of all the above mentioned rubbers with the exclusion of nitrile rubber. Indeed, it was experimentally verified that polyisoprene, polybutadiene and SBR are easily soluble in biodiesel while polystyrene gives a cloudy solution. Considerations on the solubility parameter of the biodiesel and of a series of rubbers have led to the conclusion that biodiesel behaves essentially as an internal lubricant in a diene rubber matrix, the same situation occurs with the common aromatic mineral oil plasticizer known as T-RAE. The experimental evaluation of biodiesel as plasticizer in an SBR-based rubber compound in comparison to an aromatic mineral oil have led to the primary conclusion that biodiesel is reactive with the sulphur curing agent subtracting sulphur to the crosslinking polymer chains and leading to a vulcanizatewith lower moduli, tensile and hardness and higher elongationsin comparison to a reference compound fully plasticized with an aromatic mineral oil. However, biodiesel seems a good low temperature plasticizer because the low elastic modulus observed is desired in a winter tire tread for a good grip on snow and ice. The present work is only an exploratory work, and the tire tread formulation with biodiesel was not optimized.

Surface Effects on Engine Materials of Mineral Oil Dilution With Methyl Esters and Biodiesels

2020 ◽  
Vol 8 (2) ◽  
pp. 1-18 ◽  
Author(s):  
Gustavo J. Molina ◽  
Emeka F. Onyejizu ◽  
John L. Morrison ◽  
Valentin Soloiu
Keyword(s):  
Combustion Engine ◽  
Methyl Esters ◽  
Surface Effects ◽  
Mineral Oil ◽  
Engine Oil ◽  
Engine Operation ◽  
Surface Degradation ◽  
Surface Change ◽  
Main Components ◽  
Enhanced Surface

During ordinary internal-combustion engine operation, biodiesels partially mix in the engine-oil, leading to increased surface degradation, as premature wear. Biodiesels are blends of methyl esters as main components, which are dependent on the source feedstock and may lead to different surface effects on engine materials. In this preliminary study of surface change of SAE 1018 steel when adding pure methyl-esters to engine oil, a SAE 15W40 mineral oil was diluted with methyl-palmitate, -oleate, -stearate, -linoleate, -laurate and -myristate, and with two typical biodiesels, soybean oil and peanut oil biodiesel, each at six different dilutions, and tested in two different instruments. Biodiesel at just 5% in oil led to enhanced wear, but some larger fractions of methyl-oleate and -laurate produced negligible surface change enhancements. Addition of methyl-linoleate and -palmitate enhanced surface degradation. Methyl ester compositions of the two tested biodiesels and their wear trends, which are found in good agreement with previous studies, are used to explain the wear differences

REINFORCEMENT EFFECT OF IN SITU DEVELOPED ITACONIC ACID BASED METAL SALT NANO-CRYSTALS IN ACRYLONITRILE-BUTADIENE COPOLYMER

2021 ◽  
Author(s):  
Debdipta Basu ◽  
Bharat Kapgate ◽  
Naresh Bansod ◽  
Kasilingam Rajkumar ◽  
Suchismita Sahoo ◽  
...  
Keyword(s):  
Tensile Strength ◽  
Metal Oxides ◽  
Itaconic Acid ◽  
Metal Ion ◽  
Nitrile Rubber ◽  
Rubber Matrix ◽  
Butadiene Rubber ◽  
Rubber Composites ◽  
Covalent Bonds ◽  
Ionic Crosslinking

ABSTRACT Itaconic acid has been employed as a special facilitator to construct divalent metal ion based ionic crosslinking framework in the acrylonitrile butadiene rubber matrix. Readily accessible double bonds in itaconic acid could directly react with the elastomer to form effective covalent bonds. On the other hand, presence of easily dissociable protons in itaconic acid enables them to form ionic bonds that leads to an increase in crosslinking density of the vulcanizates. The synergistic effect of covalent crosslinking induced by peroxide and ionic crosslinking induced by metal carboxylate could effectively enhance the overall mechanical and dynamic mechanical properties of the rubber composites. In this study, three metal oxides, that is, zinc oxide, magnesium oxide, and calcium oxide, have been selected for this purpose. Tensile strength of nitrile rubber composites depends on the strength of ionic crosslinks, which in turn is influenced by the size of the alkaline earth metals, such as Mg, Ca, etc., and stoichiometric quantity of itaconic acid, which is at par in the formulation of this study. The novelty of this study is that the introduction of a dicarboxylic acid in combination with metal oxides enhances the crosslink density and tensile strength of nitrile rubber composites which could result from the metal organic framework.

Anisotropic Damage Phenomena in Filled Elastomers: Experimental Observation and Constitutive Modeling

2013 ◽  
Vol 577-578 ◽  
pp. 161-164
Author(s):  
Mikhail Itskov ◽  
Roozbeh Dargazany
Keyword(s):  
Network Model ◽  
Polymer Chains ◽  
Rubber Matrix ◽  
Present Contribution ◽  
Cell Network ◽  
Filled Elastomers ◽  
Polymer Filler ◽  
Filler Network ◽  
Microscopic Damage ◽  
Filler Cell

Most important macroscopic inelastic phenomena of filled elastomers are due to microscopic damage processes inside the rubber network. For example, the Mullins effect can be explained by debonding of polymer chains from the carbon black aggregates. In turn, the damage and following recovery of aggregates are responsible for the hysteresis. All these effects also induce anisotropy of an initially isotropic material. In the present contribution, we show how these effects can be quantified experimentally and simulated by a micro-mechanical model. The model is based on the decomposition of the rubber matrix into a purely elastic polymer, a polymer-filler and a filler cell network. The polymer-filler network model takes into account the debonding of polymer chains from filler aggregates and is thus able to predict the strain induced damage and the permanent set. The filler cell network model describes breakage and recovery of filler aggregates and is responsible for the hysteresis. The presented model is in accord with a broad range of experimental observations.

Characterizing Mechanical Properties of Peroxide-Vulcanized Natural Rubber Latex Films

2015 ◽  
Vol 1134 ◽  
pp. 236-242 ◽  
Author(s):  
Roslim Ramli ◽  
Jefri Jaapar ◽  
Manroshan Singh Jaswan Singh ◽  
Siti Noor Suzila Maqsood Ul Haque ◽  
Amir Hashim Md Yatim
Keyword(s):  
Free Radicals ◽  
Natural Rubber ◽  
Polymer Network ◽  
Natural Rubber Latex ◽  
High Strength ◽  
Barrier Properties ◽  
Organic Peroxide ◽  
Polymer Chains ◽  
Rubber Matrix ◽  
Rubber Latex

Natural rubber latex is the material of choice for the fabrication of thin elastic films in many products such as gloves and condoms owing to its high strength, elasticity, comfort in use, good barrier properties and ‘green image’ [1, 2]. This unique combination of characteristics has its origins in the intrinsic properties of the crosslinked polymer network within the rubber matrix. The crosslinking of rubber hydrocarbon chains by free radicals generated from peroxide has been discovered for many years [3]. In peroxide crosslinking reactions, organic peroxide decomposes to produce reactive free radicals that will react to release hydrogen ions from the carbon hydrogen in the polymer chain, encouraging formation of free radicals on the rubber molecular chains. As the free radicals react with the polymer chains, the carbon hydrogen in the chains act as reactive centre that combines with centres of other rubber chains to form a network of carbon to carbon bonds which serve as crosslinks [3, 4].

Friction on Ice

1988 ◽  
Vol 61 (1) ◽  
pp. 14-35 ◽  
Author(s):  
Asahiro Ahagon ◽  
Toshio Kobayashi ◽  
Makoto Mlsawa
Keyword(s):  
Melting Point ◽  
Energy Loss ◽  
Solubility Parameter ◽  
Low Temperatures ◽  
Fluid Layer ◽  
Frictional Resistance ◽  
High Viscosity ◽  
Polymer Chains ◽  
Solid Surfaces ◽  
Ice Surface

Abstract The friction on ice is strongly dependent on temperature. At sufficiently low temperatures, the frictional resistance on ice is high comparable to those on wet or even dry solid surfaces. As temperature rises and approaches the melting point of ice, however, friction rapidly decreases. Differing from the friction of a rubber on ordinary dry or wet solid surfaces the energy loss processes in the rubber do not seem to be the direct source of the frictional resistance on ice. Although frictional melting of ice could occur at high sliding speeds, an ice surface is inherently lubricated with a persistent mobile fluid layer at relatively high temperatures, near the melting point of ice. When a rubber slides on an ice surface, the fluid layer is sheared and undergoes drag flow. The energy loss process necessary for the frictional resistance takes place primarily in the fluid layer, and not in the rubber. The frictional resistance on ice is primarily determined by the viscosity and the thickness of the lubricating fluid layer. What is required of a rubber for better traction under such a condition is that the rubber surface follows the topography of the ice surface as closely as possible, so that more patches of ice surface can be sheared. Therefore, the rubber has to be sufficiently soft to show high friction on ice. Further improvement of the friction could be obtained by making it more resilient. Thus, a rubber with high friction on ice must be compounded so that the polymer chains maintain a high level of mobility at moderately low temperatures. This can be achieved by using polymers with low glass-transition-temperatures. An increased softener loading level helps to improve friction, but to a limited extent. In order to take maximum advantage of softeners, the choice of softener system is important. A relation common to all the mixed softener systems, except the ones containing high-viscosity softeners, was found to exist between the friction on ice and the solubility parameter of the softener mixture in the rubber. The friction on ice was maximized by selecting a softener system with a solubility parameter near that of the polymers in the rubber. The solubility parameter dependence of the friction was consistent with those of softness and resilience.

Carbon black/polypyrrole/nitrile rubber conducting composites: synergistic properties and compounding conductivity effect

e-Polymers ◽  
2011 ◽  
Vol 11 (1) ◽  
Author(s):  
Hsien-Tang Chiu ◽  
Tzong-Yiing Chiang ◽  
Chi-Yung Chang ◽  
Ming-Tai Kuo
Keyword(s):  
Thermal Stability ◽  
Carbon Black ◽  
In Situ Polymerization ◽  
Thermo Gravimetric Analysis ◽  
Single Step ◽  
Nitrile Rubber ◽  
Rubber Matrix ◽  
Gravimetric Analysis ◽  
Mechanical Mixing ◽  
Conducting Composites

AbstractElectrically conducting nitrile rubber (NBR) containing electro-conductive carbon black (CB) and polypyrrole as conducting-modifier were prepared by single-step in situ polymerization with mechanical mixing and compression molding (vulcanized). Our result showed CB/NBR and CB/ polypyrrole /NBR conducting composites presents high thermal stability. Thermo-gravimetric analysis showed that the CB 50 phr / polypyrrole 10 phr /NBR of composites formula has highest thermal stability with improved degradation temperature from 422 °C (NBR matrix) to 440 °C at 10% weight loss. CB 50 phr and polypyrrole 10 phr has still optimum volume resistivity values 2.83×1010 to 2.03×103 ohm-cm above the percolation threshold. Therefore, incorporating CB with polypyrrole conducting-modifier showed four causes of advantage i.e. increase in thermal stability, conductive pathways, synergistic properties on thermal stability with reinforcement mechanical properties and compounding conductivity effect within the rubber matrix.

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