ABSTRACT
The last decade has seen a slow but steady move toward the use of “environmentally friendly” or more readily biodegradable lubricant fluids. Biodegradability has become one of the most important design parameters both in the selection of the base fluid and in the overall formulation of the finished lubricant. By more readily biodegradable it is meant that the fluids, using standard methods and assays, are converted from the lubricating fluids to lower molecular weight components that have essentially no environmental impact. The rate at which lubricants, and other chemicals or additive components, biodegrade is related to their chemical structure. Their chemical structure affects their properties, many of which affect performance in the various tests for biodegradability. For example, water solubility is critical in some tests for biodegradability, and toxicity is very important, because if the lubricant is toxic and reduces the organism population, then this directly and negatively impacts the process of biodegradation.
