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Lubricating oil contain always different types of additives. Viscosity is one of the most important and visible property of a fluid. Modern lubricants, especially motors oils, contain polymeric additives that modify the viscosity characteristics of the lubricants. These additives are called viscosity modifiers or viscosity index improvers. The dewaxing process is used to lower the pour point of the oil. In the present work, some polymeric additives were prepared via copolymerization of different α-olefins with different esters of acrylic acid and used as pour point depressants and viscosity index improvers for lubricating oil. The efficiencies of the prepared compounds as pour point depressants and viscosity index improvers were investigated. It was found that the efficiency of the prepared compounds as pour point depressants increases with decreasing the concentration of the prepared polymers, increasing the chain length of alkyl groups and with decreasing the molecular weight of the prepared polymers. The efficiency of the prepared compounds as viscosity index improvers increases by increasing the concentration of these additives and by increasing the molecular weight of polymers. [ABSTRACT FROM PUBLISHER]

Schiff base prepared from salicylaldehyde and diethylene triamine was ethoxylated by poly (ethylene glycol) of different molecular weights, namely 200, 600, 1000 and 2000, by using β,β-dichlorodiethyl ether as a linking agent. The ethoxylation reaction took place at both ends of the base upon using poly(ethylene glycol) (PEG) 200 and 600, whereas at one end when PEG 1000 and 2000 were used. The chemical structure of the prepared compounds was confirmed by using IR and 1HNMR spectroscopy. Thermodynamic parameters for micellization and adsorption or the prepared compounds were measured based on the surface tension of their solutions at different temperatures. Then, the compounds under investigation were tested as oil spill dispersants according to different standard test methods. It was found that the compounds with lower molecular weights of PEG showed the best dispersancy. [ABSTRACT FROM AUTHOR]

With increasing demands being placed on lubricants for automotive engines and transmissions, it has been necessary to work to improve the function of these lubricants. Modern lubricants are formulated from a range of base fluids and chemical additives to enhance their actions or to add new properties. In this study we have confined ourselves to the study of the detergent/dispersant type of additives based on preparation of polyisobutylene succinic anhydride (PIBSA) and then the reaction of PIBSA with different polyethylene glycols and the amination of the products by different polyamines. The compositions of the prepared compounds were determined by molecular weight, I.R. and H-NMR spectroscopy. The efficiency of the prepared compounds as antioxidants and detergents/dispersants was investigated. It was found that the prepared compounds have very good dispersancy power and the efficiency increases by increasing the number of -NH groups in the prepared compounds and by increasing the molecular weight of the polyethylene glycols. [ABSTRACT FROM AUTHOR]

Lube oil additives are essential for all types of lubricating oils; they are added either to give the oils new properties as detergency and oxidation stability or to improve such properties as pour point and viscosity index. They are added at varying proportions to meet the performance requirements. The present work is concerned with studying of detergent/dispersant type additives based on synthesized polyisobutylene succinic anhydride (PIBSA) and its aminated compounds (PIBSA) with different types of polyethylene polyamine such as ethylene diamine, diethylene Triamine, Triethylene tetramine, and tetraethylene pentamine. Different types of polyisobutylene succinimides were reacted with dodecylphenol and formaldehyde to prepare different type of Mannish bases. The efficiency of the prepared compounds as antioxidants and detergents/dispersants was investigated. It was found that compound D 1 (Mannich base IV) is the best antioxidant additive for lube oil, and all the prepared compounds have excellent dispersancy power. [ABSTRACT FROM AUTHOR]