Lubricant Basestocks High Viscosity

The ideal diester for use in a partial synthetic lubricant, i.e. blend of diester, petroleum basestock and additives, should have the lowest viscosity at both high and low temperatures, and also be the least volatile. Of course, it would also need to be resistant to oxidation and corrosion and provide lubrication and wear protection when compounded into a finished lubricant. The low viscosity requirement of the synthetic portion of the partial synthetic lubricant is for economic reasons. The synthetic portion is substantially more expensive than the petroleum portion and the lower the amount required to achieve the low viscosity of the final oil, the better the final economics. As mentioned earlier, the low volatility is desirable to prevent carrying the... 

Due to an increasing demand in performance of lubricants, characterizing a basestock is often complex and requires the measurement of many chemical and physical properties. Viscosity, which measures the fluidity of the basestock ranges from 2 to 20 cSt 100°C for Neutrals and can be as high as 32cSt for Bright stocks. The most common method used is Brookfield viscosity. The viscosity Index or VI... 

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