Summary of Article: It's Not your Father’s Motor Oil By MoleKule Keywords: Modern Motor Oils; lubrication, seed oils, STLE, Tribology and Lubrication Technology (TLT), History of Lubrication. 1.0 General This is a summary of a recent article found in TLT, June 2006, by Dr. Alan C. Eachus. The general tone of the article is that alternative synthetic base oils, and especially bio-based oils and complex esters, will probably replace mineral oils in the future. The reason is because synthetic oils have low volatility, good inherent viscosity indexes, good lubricity, good low temperature flow, and high stability at high operating temps. A discussion of various synthetic oils, including seed or “bio-based” oils is given with an explanation of each synthetic oil type. 2.0 First, An Interesting Quote. When discussing polyol esters (POE), a number of esters were defined, such as TMP, or trimethylol propane and pentaerythritol, PE. An interesting paragraph follows: “TMP esters of certain cuts from coconut oil and palm kernel oil acids (C-8 and C-10 saturated acids) are more suited to withstand the stresses placed on motor oils. Hatco ester engineers created the frst qualified synthetic motor oil in the United States in the early 1970’s, which was marketed by Amsoil.” Now, we don’t know if this is bad editing or was purposely meant to infer that Hatco had developed a coconut oil esters for the original Amsoil 10W40. But the article does say that Hatco chemists developed the first Amsoil formulation. Now this is not unusual since outside firms often develop formulations for companies that market, reather than formulate, their own oils. Hatco is a leading developer and formulator of esters. [We know that for Mobil’s TriSyn, it contained, as one of its three synthetic base oils, a coconut-oil-acid derived ester. This was disclosed in a paper referred to earlier here on BITOG] Amsoil has stated in various Amsoil and trade publications that his original API qualified synthetic 10W40 was of a diester-based design, and hinted or inferred its was an Amsoil design. Many in the industry had suspected for some time that someone other than Amsoil had developed this oil, and that it contained diesters as well as vegetable oil derived esters. And it could the diester was a vegetable-based diester. Many now believe that modern Amsoil and Mobil synthetics contain mostly PAO’s with some type of ester, most likely TMP for Amsoil and TME for Mobil, with alkylated naphthalenes as solving agents. We know that reduced detergents and dispersants can be used in PCMO formulations if AN’s are used because of their solvency characteristics. http://theoildrop.server101.com/cgi/ultimatebb.cgi?ubb=get_topic;f=56;t=000006 3.0 Renewable oils (Seed oils). The article goes on to say that genetic modification will produce better seed oil with reduced glycerol, which contains hydrogen molecules that tend to cause “…decomposition attack and hydrolysis.” The triglycerides (or naturally occurring fatty-acid esters of gylcerol) offer excellent lubricity, but need improvement for thermal and oxidation instabilities. It was also stated that the isostearic acid from plant oils can be used to make a polyol ester with improved oxidation stability and lower pour points. Also, “…Oleochemical esters made using naturally-derived fatty acids and petroleum-derived polyols will demonstrate a greater degree of biodegradeability and renewability than will diesters.” In addition, new anti-oxidants are being developed for plant oils that will allow these oils to have reduced oxidation potential. 4.0 Complex Esters. “Complex esters are synthesized from various reactant mixtures of mono-hydric and poly-hydric alcohols and poly-functional acids.” These complex esters have better low-temperature flow and oxidation resistance than even current polyol esters. However, complex esters are among the most expensive of esters. IMHO, one of the better papers from TLT in the last two years.