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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 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 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.