Influence of Chemical Structure on the Boundary Lubrication Properties of Vegetable Oils

2010 ◽  
Author(s):  
Jagadeesh K. Mannekote ◽  
Satish V. Kailas
Keyword(s):  
Vegetable Oils ◽  
Boundary Lubrication ◽  
Castor Oil ◽  
Unsaturated Fatty Acids ◽  
Wear Scar ◽  
Hydroxyl Group ◽  
Accelerated Ageing ◽  
Wear Scar Diameter ◽  
Different Levels ◽  
Lubrication Properties

Vegetable oils are increasingly used as lubricant base oils, because of sustainability issues and regulations. In present study coconut, palm, sunflower and castor oils were used to represent different levels of unsaturation, where as castor oil was selected to represent influence of hydroxyl group. The effect of oxidation on the boundary lubrication properties was evaluated by subjecting the oils to accelerated ageing at 333,353 and 373 k according to AOCS method. The experiments were carried out by using of four ball tester increase in observed wear scar diameter with temperature was more with oil having higher percentage of unsaturated fatty acids. At the same time it was also observed that increase in wear scar diameter with temperature was more with castor oil compared to other oil samples. The poor boundary lubrication properties observed with aged oil samples was possibly due to the deterioration of the triglyceride structure.

Antiwear and extreme pressure performance of castor oil with nano-additives

2017 ◽  
Vol 232 (9) ◽  
pp. 1055-1067 ◽  
Author(s):  
Rajeev Nayan Gupta ◽  
AP Harsha
Keyword(s):  
Castor Oil ◽  
Sodium Dodecyl ◽  
Wear Scar ◽  
Suspension Stability ◽  
Additive Concentration ◽  
Extreme Pressure ◽  
Wear Scar Diameter ◽  
Load Carrying ◽  
Nano Additives ◽  
Analytical Tools

The aim of the present study is to examine the antiwear, antifriction, and extreme pressure performance of castor oil with nano-additives by using a four-ball tester. CeO2 (≈90 nm) and polytetrafluroethylene (≈150 nm) nanoparticles were used as an additive in castor oil with four different concentrations in the range of 0.1–1.0% w/v. The suspension stability of the nanoparticles was improved by using sodium dodecyl sulfate as a dispersant. Different analytical tools were used to characterize the nanoparticles parameter (i.e. shape and size) as well as the worn surfaces. The additive concentration was optimized on the basis of tribological performance. The test results of antiwear and extreme pressure property have been reported on the basis of wear scar diameter and weld load, respectively. For the antiwear test, it was observed that the maximum reduction in the wear scar diameter was 37.4 and 35.3% at an optimum concentration of CeO2 and polytetrafluroethylene additive, respectively. Also, antifriction and load carrying properties of castor oil were significantly improved with the addition of nanoparticles as an additive in a small amount. The mechanism for such improvement in the tribological behavior has also been discussed.

Experimental investigation on the tribological properties of modified carbon nanotubes as the additive in castor oil

2018 ◽  
Vol 70 (3) ◽  
pp. 499-505
Author(s):  
Shanhua Qian ◽  
Hongyue Wang ◽  
Chuanhui Huang ◽  
Yongwu Zhao
Keyword(s):  
Carbon Nanotubes ◽  
Coefficient Of Friction ◽  
Tribological Properties ◽  
Castor Oil ◽  
Friction And Wear ◽  
Engineering Application ◽  
Wear Scar ◽  
Wear Scar Diameter ◽  
Content Type ◽  
Modified Carbon Nanotubes

Purpose This paper aims to modify carbon nanotubes with oleic acid, and to study the tribological properties of castor oil with modified carbon nanotubes additives. The proper additives are sought for the future engineering application of castor oil. Design/methodology/approach Tribological properties of the castor oils mixed with the modified carbon nanotubes of four mass percentages were investigated using a four-ball testing rig. Coefficient of friction and wear scar diameter were obtained in each test, and the mechanism of modified carbon nanotubes and castor oil was discussed. Findings The results indicated that modified carbon nanotubes had better dispersion in castor oil. Coefficient of friction first increased, then decreased and finally grew stable with the time, and wear scar diameter of steel surface functioned as a first reduced then increased change with the additive mass percentage of modified carbon nanotubes. The minimum of average coefficient of friction and wear scar diameter occurred at 0.02 Wt.% modified carbon nanotubes. Originality/value A small amount of modified carbon nanotubes could improve properties of the castor oil, and the mixed castor oil with 0.02 Wt.% modified carbon nanotubes would be most possibly used in engineering applications.

scholarly journals Tribochemistry and EP Activity Assessment of Mo-S Complexes in Lithium-Base Greases

2008 ◽  
Vol 2008 ◽  
pp. 1-6 ◽  
Author(s):  
Tarunendr Singh
Keyword(s):  
Electron Spectroscopy ◽  
Auger Electron ◽  
Wear Scar ◽  
Extreme Pressure ◽  
Flash Temperature ◽  
Wear Scar Diameter ◽  
Activity Assessment ◽  
Temperature Parameter ◽  
Ball Test ◽  
Base Grease

The blends of bis(1,5-diaryl-2,4-dithiomalonamido)dioxomolybdenum(VI) complexes in lithium-base grease are evaluated for their extreme pressure activity in a “four-ball test” using 12.7 mm diameter alloy steel ball specimen. The additive, bis(1,5-di-p-methoxyphenyl-2,4-dithiomalonamido)dioxomolybdenum(VI) and bis(1,5-di-p-chloro-phenyl-2,4-dithiomalonamido)dioxomolybdenum(VI) exhibited lower values of wear-scar diameter at higher load and higher values of weld load, flash temperature parameter, and pressure wear index as compared with lithium-base grease without additives. The greases fortified with the developed additives prevent rusting and corrosion of bearings while grease containing no additives did not pass these tests as per the standard tests. These greases have also better oxidation protection as compared to the grease that has no additive. The topography and tribochemistry of the wear-scar surface are carried out by means of scanning electron microscopy and Auger electron spectroscopy techniques, respectively.

scholarly journals Production of biodiesel from babassu oil using methanol-ethanol blends

2018 ◽  
Vol 35 (1) ◽  
pp. 47
Author(s):  
Fernando Carvalho Silva ◽  
Kiany Sirley Brandão Cavalcante ◽  
Hilton Costa Louzeiro ◽  
Katia Regina Marques Moura ◽  
Adeilton Pereira Maciel ◽  
...  
Keyword(s):  
Specific Gravity ◽  
Vegetable Oils ◽  
Castor Oil ◽  
Kinematic Viscosity ◽  
Volume Ratio ◽  
Biodiesel Production ◽  
Mass Yield ◽  
A Value ◽  
Oil Plant ◽  
Ethanol Blends

Maranhão state in Brazil presents a big potential for the cultivation of several oleaginous species, such as babassu, soybean, castor oil plant, etc... These vegetable oils can be transformed into biodiesel by the transesterification reaction in an alkaline medium, using methanol or ethanol. The biodiesel production from a blend of these alcohols is a way of adding the technical and economical advantages of methanol to the environmental advantages of ethanol. The optimized alcohol blend was observed to be a methanol/ethanol volume ratio of 80 % MeOH: 20 % EtOH. The ester content was of 98.70 %, a value higher than the target of the ANP, 96.5 % (m/m), and the biodiesel mass yield was of 95.32 %. This biodiesel fulfills the specifications of moisture, specific gravity, kinematic viscosity and percentages of free alcohols (methanol plus ethanol) and free glycerin.

Comparative Study of Physico-Chemical Properties of Pure Polyurethane and Polyurethane Based on Castor Oil

2014 ◽  
Vol 983 ◽  
pp. 39-43
Author(s):  
M. A. Alaa ◽  
Kamal Yusoh ◽  
S.F. Hasany
Keyword(s):  
Castor Oil ◽  
High Performance ◽  
In Situ Polymerization ◽  
Chemical Properties ◽  
Strength Properties ◽  
Hydroxyl Group ◽  
Physico Chemical ◽  
Analysis Technique ◽  
Hydrophobic Nature ◽  
Poly Propylene

Petroleum based polyurethanes are contributing major portions in the world requirement. To overcome the environmental issues and price adaptability, there is always a massive demand of utilization of renewable resources for polyurethane synthesis with comparable physico-chemical properties. Castor oil is the only major natural vegetable oil that contains a hydroxyl group (-OH) and unsaturated double bonds (C=C) in its organic chain and therefore can be employed with or without modification due to the excellent properties derived from the hydrophobic nature of triglycerides. In this study, physico-chemical properties of high performance polyurethane synthesized from Poly propylene glycol (PPG) in comparison with a combination of PPG and Castor oil (a renewable source), by in situ polymerization technique has been studied. The variations in properties of both types of polyurethanes are evaluated by Fourier Transform Infrared Spectroscopy (FTIR), Scanning Electron Microscopy (SEM) and Thermogravimetric analysis technique (TGA). Tensile strength properties were investigated by Film Tensile testing equipment. Results indicated the presence of large-CH stretching in castor oil mixed polyurethane with a larger oxidative thermal stability, over a pure PPG polyurethanes. Tensile properties were found almost comparable in pure and mixed polymers, which signify the usage of mixed polymer in coming future, to overcome the environmental and economical crisis in polyurethanes synthesis.

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