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The paper aims to study the effects of introducing oxypropyl segments into the trimethylolpropane (TMP) esters along with lowering the linear chain length from C₅‐C₉ to C₅‐C₆ on the properties of base lubricants.

Various amounts of oxypropylene segments were introduced into the TMP skeleton and obtained polyols subsequently esterified by pure C₅‐, C₆‐, and mixture of C₅‐C₆‐ aliphatic monocarboxylic acids of normal structure (SFAc mixture).

Introducing oxypropylene segments into TMP skeleton, along with lowering the carboxylic acid chain length from C₅‐C₉ to C₅‐C₆, ester base lubricants obtained improved mechanical and wear preventive characteristics.

Because of complexity of obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

The obtained materials have high boiling points under reduced pressure (2 mmHg). Producing higher vacuums will make the distillation process easier.

This paper fulfils detail information on the experimentally preparation of oxypropylated TMPs as synthetic base lubricants. The synthesized compounds showed improved properties such as high viscosity at 100°C, low pour point, high flash point, and totally excellent viscosity‐temperature properties than simple TMP esters and some literature reported ester base lubricants.

The purpose of this paper is to study the influence of structural parameters of oil groove (such as central angle number, depth and so on) on pressure, flow, load capacity and transmitted torque between friction pairs of hydro-viscous clutch.

According to the working process of friction pairs of hydro-viscous clutch, mathematical models of hydrodynamic load capacity and torque transmitted by the oil film were built based on viscosity-temperature property. Then analytical solutions of pressure, flow, load capacity and transmitted torque were obtained; effects of central angle of oil groove zone and friction contact zone, oil film thickness, number of oil grooves on pressure, flow, load capacity and torque were studied theoretically.

The research found that the central angle of oil groove zone, number of oil grooves and oil groove depth have similar effects on flow, which means that with the increase of central angle, number or depth of oil grooves, the flow also increases; pressure in friction contact zone and oil groove zone drops along radial direction, whereas its value in oil groove zone is higher. With the increase of the central angle of oil groove zone, pressure in friction contact zone and friction contact zone rises, and the load capacity increases, whereas the transmitted torque drops. Number of oil grooves has little effect on load capacity. When the oil film thickness increases, its flow increases accordingly, whereas the pressure, load capacity and transmitted torque drops. Meanwhile, the transmitted torque decreases with the increase of number of oil grooves, whereas the oil groove depth nearly has no effects on transmitted torque.

In this paper, mathematical models of hydrodynamic load capacity and torque transmitted by oil film were built based on viscosity-temperature property in the working process of hydro-viscous clutch, and their analytical solutions were obtained; effects of structural parameters of oil groove on transmission characteristics of hydro-viscous clutch based on viscosity-temperature property were revealed. The research results are of great value to the theory development of hydro-viscous drive technology, the design of high-power hydro-viscous clutch and relative control strategy.

The purpose of this paper is to examine the preparation of asymmetric mixed esters of methylolcyclohexanols in order to decrease the pour point and increase the thermal stability of base oils.

The aldol condensation reaction of cyclohexanone with paraformaldehyde is modified to give mixture of alicyclic polyols. The obtained mixture was subsequently esterified by different pure and mixed linear mono carboxylic acids to give asymmetric mixture of esters of methylolcyclohexanols/ones.

The obtained base lubricants showed better wear preventive characteristcs (four‐ball rolling contact test) compared with previously reported and commercially available ester base lubricants.

Because of the complexity of the obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

The obtained materials are slightly acidic and should be neutralized before use or formulation.

The paper presents a new process for obtaining synthetic ester base lubricants from mixed polyols of neo structure, which was obtained from aldol condensation reaction of cyclohexanone and paraformaldehyde, and linear aliphatic monocarboxylic acids. The key step in this process is modifying the reaction condition for obtaining mixture of polyols, and not pure 2,2,6,6‐tetramethylolcyclohexanol. This allows one to obtain asymmetrical and complex mixture of esterification products, which is favored in the production of synthetic ester base stocks, having excellent viscosity‐temperature properties, decreased pour point, and increased thermal stability. The synthesized ester base lubricants also show excellent viscosity‐temperature properties compared with ester base lubricants of the same family.

The aim of this paper is to focus on the production of mixed‐synthetic diester base oils from the waste of electrochemical production of sebacic acid (mixtures of methyl esters of dicarboxylic acids, HOOC(CH₂)nCOOH, n=4, 6, 8).

The mixtures of methyl esters of dicarboxylic acids ((CH₂)n, n=4, 6, 8) are transesterified by pure alcohols and also different mixtures of aliphatic monohydric alcohols, C6‐C10 of iso‐ and normal structure, in the presence of a new catalyst system (tetra‐n‐butyl orthotitanate, Ti(O‐n‐Bu)₄). The effects of starting materials ratios on the reaction progress and characteristic features of the obtained diester oils have been studied.

The obtained mixed diester oils showed similar thermal properties and low pour point (minimum −70°C), and improved viscosity‐temperature properties compared with commercially available dioctyl sebacate (DOS) and dioctyl adipate (DOA) diester oils.

Because of the complexity of the obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

The mixtures of methyl esters of dicarboxylic acids obtained from different batches of sebacic acid production have different molar ratios and must be analyzed before use. The process is based on transesterification reactions of methyl esters of mixture of the aliphatic dicarboxylic acids ((CH₂)n, n=4, 6, 8) by mixture of aliphatic alcohols having iso‐ and normal structure in the presence of a new transesterification catalyst (mixture of p‐toluene sulfonic acid and tetra‐n‐butyl orthotitanate). The obtained mixed diester oils showed similar thermal properties, low pour point (minimum −70°C) and improved viscosity‐temperature properties compared with commercially available DOS and DOA diester oils.

The paper illustrates a new process for the production of mixed‐synthetic diester base oils.

The physical and chemical properties of a new class of synthetic lubricants, the perfluoroalkylpolyether oils and the polytetrufluoroethylene‐thickened greases made from these oils, are described in some detail. The properties which make these products of interest as lubricants for use under severe conditions are shown to be I) excellent thermal and oxidative stability, 2) extreme inertness to many reactive chemicals, 3) broad liquid range and good viscosity‐temperature characteristics, 4) complete nonflammability, 5) good lubricating qualities, 6) compatibility with most elastomers and metals at suitable operating temperatures and 7) insolubility in most common solvents. The commercial process used in the production of these lubricants is described. The oils are disclosed to be fluorine end capped polymers of hexafluoropropylene epoxide having number average molecular weights of from 2000 to 7500, and the preferred thickener for the greases is disclosed to be a telomer of tetrafluoroethylene having a molecular weight of 20,000 to 30,000. A number of the commercial uses of these oils and greases, sold by Du Pont under the trade‐name Krytox®, are described including specific examples of instances where their performance far exceeded that of other available lubricants. Some uses in the space and aircraft industries are also discussed.

To prepare semi‐synthetic oils satisfying the classification API SF/CC and SAE 10W30 from mineral base oils derived from high paraffinic petroleum, synthetic alkylbenzenes base oils, and suitable additives.

The mixtures of base mineral oils of deep hydro‐isomerization derived from high‐paraffinic petroleum (viscosity at 100°C is 12.5 cSt) and the mixtures of the synthetic alkyl aromatics oils with the naphthenic components (viscosity at 100°C of 8.0 cSt) were used as base oil. viscosity‐temperature properties, pour points, and flash points were modified by mixing of suitable additives. Octan M‐1, Octan M‐2, Octan M‐3, and Octan M‐4 oils were obtained by application of suitable additives into the prepared base oils B‐C. In order to get the SAE 10W30 requirements the viscous additive was added (0.4‐0.6 mass percent) to prepared base oils. For obtaining the API/SF/CC grade oils, package additive (Hitec 9229) additive was added (4.7 mass percent) to the mixture. The oil (Octan M‐1) was tested in the engine of Mercedes‐Benz model 230 car and positive results over 20,000 km running.

It was observed that, viscosities and pour points change linearly as the mass percent of alkylbenzenes the in the base oil mixture is changed. This realizes the possibility of the creation of semi‐synthetic motor oil of desired properties in the case of lack of other low‐viscosity synthetic component such as poly‐á‐olefins, diester and polyester oil. The obtained oils are useful for service in relatively mild climatic conditions (average temperature of the winter period −15 to −30°C).

The obtained oils cannot fully satisfy the requirements of the engines by pour point and low‐temperature characteristics in the absence of additives.

Because of complexity of obtained mixture, it was impossible to study the structure and composition of the obtained products by modern techniques such as high field NMR spectroscopy.

Details practical information on preparation of four semi‐synthetic oils satisfying the classification API SF/CC are reported.

ALTHOUGH the element silicon is second only to oxygen in order of abundance in the earth's crust the chemistry of its compounds and in particular of organo‐silicon compounds had developed but little before the turn of the century. It is true that the German chemist Friedel and his students Crafts and Ladenburg and later Polis prepared a few isolated organo‐silicon compounds during the latter half of the nineteenth century (1863–1886), but the land mark in this field is undoubtedly the classical work of Professor F. S. Kipping and his school at University College, Nottingham. This work extended over nearly forty years from 1899 to 1937 during which time a systematic study was made of this branch of chemistry.

This paper seeks to address the preparation of new compositions of hydrophobicizing liquids as release agent for press moulds in the production of plastic articles of all kinds of polymers.

Mixtures of thermo‐stable polyethers (copolymer of ethylene oxide and propylene oxide) and polyols esters/mixed esters in the presence of phenothiazine as antioxidant were prepared and tested.

All compositions were tested and compared with silicone oil polymethylsiloxane‐100 (PMS‐100). The lubricant was manually applied on a hot surface (160‐190°C) of tray of press mould, without any change in the operating cycle. The finished products were easily removed from press mould, and showed higher durability. The release agent was also checked for production of polyethylene lids by automatic moulding at 170‐200°C, and 17 lids have been obtained on one application. This is quite a good result compared with silicone oil PMS‐100, which produced only four to five lids.

Because of complexity of obtained mixture, it was impossible to study the structure and composition of the obtained products by modern spectroscopy techniques.

In order to obtain compositions of optimum properties a lot of mixtures were prepared and tested. Only compositions which showed suitable properties were reported.

This paper provides detailed information on the experimental preparation of 37 compositions for hydrophobicizing mould release agents. Testing of different obtained hydrophobicizing liquids showed positive results, in production of plastic household articles, over silicone oil PMS‐100. The finished products were easily removed from press mould and prepared hydrophobicizing liquids showed higher durability than silicone oil PMS‐100. The obtained compositions are also favored from the point of view of commercial availability and ecology and can be considered as replacements for PMS‐100 release agent.

This paper aims to use this method to explore a new approach and possible technical optimal design for lubricant formulation.

The component of the developed oil was determined based on the physical and chemical properties of the base oil and the tribological properties. The analytic hierarchy process (ANP) method and SuperDecisions software were used for hydraulic oil modeling and calculation while taking performance index, work circumstance and economy into consideration.

The hydraulic oil formulation can be optimized using the ANP method, where the technical performance, economy and working circumstances of the hydraulic oils were taken into consideration in the evaluation system. The experiment analyzed and scored and screened the hydraulic oil formula in an objective and comprehensive manner.

The experiments showed that the newly developed hydraulic oils could meet the performance requirements for new energy vehicles equipped with hybrid hydraulic engines.

AN important phase in the rapid development of the aircraft gas turbine engine has been the development of new synthetic lubricants which possess an essential combination of properties unobtainable with conventional petroleum lubricants. Details concerning the performance of these oils were recently given in a paper presented to the Society of Automobile Engineers at Tulsa, by Messrs. A. B. Crampton, W. W. Gleason, W. E. Lifson, and E. F. H. Pennekamp, all of Esso Laboratories, Research Division of Standard Oil Development Co., New Jersey.