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The purpose of this paper is to prepare novel types of copolymers and terpolymers depending on jojoba, and using them as additives for lubricating oil.

Copolymerization of 1 mole of jojoba with 2 moles of vinyl acetate and copolymerization of 1 mole of jojoba with 2 moles of vinyl pyrrolidone were carried out. Then, two series of terpolymers were prepared by reacting (jojoba: vinyl acetate: alkylacrylate) and (jojoba: vinyl pyrrolidone: alkylacrylate), using free radical chain addition polymerization. Elucidation of the prepared polymers was carried out by using Fourier transform infrared spectroscopy, proton nuclear magnetic resonance and gel permeation chromatography, for determination of weight average molecular weight. The thermal stability of the prepared polymers was determined. The prepared polymers were evaluated as viscosity index improvers and pour point depressants for lubricating oil.

It was found that the viscosity index increases with increasing the alkyl chain length of alkylacrylate. The effect of the monomer type was studied, and it was found that the polymers depending on vinyl acetate have great effect as viscosity index improvers and pour point depressants for lubricating oil.

The polymerization of jojoba as different copolymers and terpolymers was carried out. The great influence of the prepared additives on modification of the viscosity properties and pour point of the oil was observed.

This paper aims to investigate the effect of lubricant viscosity model with improver on friction and lubrication of piston skirt-cylinder liner conjunction.

A dynamic calculation model is established for the piston skirt-cylinder liner conjunction of a heavy-duty commercial diesel engine, to explore the effects of two kinds of lube oil viscosity models named after polyalkyle-metacrylate-1 (PAMA1) and styrene-isoprene-copolymer (SICP) improvers on the maximum oil film viscosity, the minimum oil film thickness, the peak oil film pressure, the maximum shear rate, the friction force and the total friction power loss.

The variation trends with the crank angle of the above parameters are not changed with the difference of improvers, while obvious numerical differences are found except the maximum oil film pressure. The minimum oil film thickness and maximum shear rate of PAMA1 are larger than that of SICP, the maximum oil film viscosity of SICP is larger than that of PAMA1, which indicates that the shear-thinning effect of PAMA1 is greater, the maximum friction force on the piston of SICP is larger than that of PAMA1, and the total friction power consumption is also larger, the average friction power consumptions of SICP and PAMA1 are 385.4 and 262.8 W, respectively, with the relative difference of 31.8 per cent.

The influence of different lubricating oil additive models on the lubrication and friction of piston skirt-cylinder liner conjunction is simulated and analyzed.

To study and estimate changes of various properties upon use of engine oil by different methods.Design/methodology/approach – By viscosity measurement, pH measurement, Fourier transform infra‐red spectroscopic analysis and UV‐Visible (Ultraviolet and visible rays) spectroscopic analysis.Findings – Some specific changes in additives of the oil upon use could be traced.Practical implications – Correct choice for additives for a particular use may enhance the oil life and also protect the engine from damage.Originality/value – The findings may be important to the lube oil producers and the users.

The purpose of this paper is to develop novel ashless additives and to meet the need for formulating ashless anti‐wear (AW) hydraulic fluid or other industrial lubricating oils. This paper also aims to investigate the tribological behaviours and mechanism of an acrylate of dialkyl dithiophosphoric acid (ADDP), as an additive in some group I/II base oils compared with some traditional s‐p containing AW additives.

ADDP is synthesized in the laboratory. The chemical composition and structure of the lubricating additive are analyzed by means of infrared spectroscopy. Its extreme pressure (EP), AW and friction reduction properties as additive in base oils, compared with some traditional s‐p containing AW additives, are investigated using a four‐ball machine according to relative testing standards. The tribological mechanism is discussed according to the scanning electron microscope (SEM) analytical data.

The results indicate that the four‐ball PB value of the prepared ADDP in HVIWH650 is better than that of the IRGLUBE 353; the thermal stability of ADDP is equivalent to the zinc dialkyl dithiophosphate (ZDDP) and the SEM data show that the prepared ADDP additive could form a layer of uniform film on the worn surface serving as lubricant and protective film. This may be the chief reason why the prepared ADDP possesses better AW property than ZDDP.

However, more experimental studies such as the synergic effect with other additives should be performed, from which it could be learned whether the novel AW additive would be applicable in industrial oils.

The results may be useful for the researchers to formulate some ashless industrial oils.

A novel additive was synthesized in the laboratory; it would find a promising industrial application as an ashless AW additive.

John Newton, Texaco Ltd, gives Chemrecon delegates an A‐to‐Z insight into lube‐oil blending, application and environmentally safe usage

Details the increasing use of BP polybutene hydrocarbons as clean, non‐polluting lubricants or viscosity index improvers for two stroke engines, compressors, metalworking fluids, gear and hydraulic oils and greases. Shows polybutene’s compatibility with mineral and synthetic oils.

The purpose of this paper is to investigate some cheap and highly stable additives to improve the quality of lubricating oil.

The study was performed using phenol, p‐cresol and pyrogallol as antioxidants. The concentration of each antioxidant was varied between 0 and 1 per cent. Sample (50 ml) blended with the antioxidant was taken in the same trap. The trap was placed on water both maintained at a temperature of 50°C. Air was bubbled for the time duration of 6 h. After 6 h, the contents of the trap were carefully collected and characterized. The oxidation was performed in a specially designed glass made U‐shaped trap in the absence and presence of antioxidants. The trap containing sample was tied with an iron stand. Air was bubbled through the sample. The bubbling was assisted by the suction pump at room temperate (24°C). The sample was aerated for time duration of 6 h. After 6 h, the contents of the trap were carefully collected in a dried bottle for physicochemical tests.

The results indicate that phenol is the best antioxidant in concentration of 0.5 per cent amongst the three antioxidants used at room temperature as well as at 50°C. Amongst the antioxidants used, the order of suitability is phenol > pyrogallol > p‐creosol.

The antioxidants studied will help increase the service time of the lubricant to save money and to avoid environmental problems arising from careless disposal of used lubricating oils.

IN THEIR PAPER BEFORE THE SOCIETY OF AUTOMOTIVE ENGINEERS at Detroit, in January, 1958, J. K. Patterson and W. E Waddey, of the Esso Research and Engineering Company, showed from comparison of results of field and engine tests that present diesel engine tests for approving engine oils are not always very reliable for predicting the field performance of oils in petrol engines. With these considerations, the engine cleanliness data from recent field tests carried out by the authors' laboratories in a variety of equipment under differing operating conditions, have been examined for a relationship with the deposits formed in laboratory Caterpillar diesel engine tests and these resuts were presented in their paper.

The subject of Horological Lubricants is one which has received very little attention in Lubrication literature. The erroneous tendency to consider that only machinery operating in very high temperatures under difficult conditions of pressure, loading or atmosphere, requires specialist lubrication care, is undoubtedly the reason for this. But the correct functioning of essential time pieces, as well as all small scientific instru‐ments, can be as vital as that of a large machine. The author had been interested in these matters for a number of years when Chief Chemist and Technical Director of Rocol Limited, in whose laboratories many of the advances described in this paper were first evolved and who have given permission for this paper to be published. This paper summarises much of the work carried out on Horological Lubricants over the past twenty‐five years.

The role that lubricating oils play is, first of all, to reduce energy loss and keep the wear and seizure to a minimum, or, in a broader sense, to improve the friction characteristics. Resistance to deterioration and prevention of rust development on metals are demanded as secondary functions. The time during which lubricating oil retains its ability to prevent any possible damage to a body in motion should be considered as its lifetime. Many functions that are provided by base oil alone are insufficient; therefore, special additives are dissolved in them. The additives for lubricating oils are of many types, and their functions are diverse and many. Those additives that are used with the purpose of improving friction characteristics are generally called oiliness improvers or friction modifiers. In this study, the protective additive's layers formed on rubbed surfaces of pins, plates and discs were investigated using pin‐on‐disc and reciprocating pin‐on‐plate test rigs. Wear tracks were examined using optical and electron microscopy with X‐ray diffraction analysis.